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-rw-r--r--media/libwebp/src/enc/alpha_enc.c445
-rw-r--r--media/libwebp/src/enc/analysis_enc.c479
-rw-r--r--media/libwebp/src/enc/backward_references_cost_enc.c795
-rw-r--r--media/libwebp/src/enc/backward_references_enc.c1068
-rw-r--r--media/libwebp/src/enc/backward_references_enc.h244
-rw-r--r--media/libwebp/src/enc/config_enc.c157
-rw-r--r--media/libwebp/src/enc/cost_enc.c342
-rw-r--r--media/libwebp/src/enc/cost_enc.h82
-rw-r--r--media/libwebp/src/enc/filter_enc.c235
-rw-r--r--media/libwebp/src/enc/frame_enc.c899
-rw-r--r--media/libwebp/src/enc/histogram_enc.c1248
-rw-r--r--media/libwebp/src/enc/histogram_enc.h130
-rw-r--r--media/libwebp/src/enc/iterator_enc.c459
-rw-r--r--media/libwebp/src/enc/moz.build43
-rw-r--r--media/libwebp/src/enc/near_lossless_enc.c151
-rw-r--r--media/libwebp/src/enc/picture_csp_enc.c843
-rw-r--r--media/libwebp/src/enc/picture_enc.c304
-rw-r--r--media/libwebp/src/enc/picture_psnr_enc.c258
-rw-r--r--media/libwebp/src/enc/picture_rescale_enc.c300
-rw-r--r--media/libwebp/src/enc/picture_tools_enc.c274
-rw-r--r--media/libwebp/src/enc/predictor_enc.c792
-rw-r--r--media/libwebp/src/enc/quant_enc.c1398
-rw-r--r--media/libwebp/src/enc/syntax_enc.c388
-rw-r--r--media/libwebp/src/enc/token_enc.c262
-rw-r--r--media/libwebp/src/enc/tree_enc.c504
-rw-r--r--media/libwebp/src/enc/vp8i_enc.h523
-rw-r--r--media/libwebp/src/enc/vp8l_enc.c2198
-rw-r--r--media/libwebp/src/enc/vp8li_enc.h126
-rw-r--r--media/libwebp/src/enc/webp_enc.c408
29 files changed, 15355 insertions, 0 deletions
diff --git a/media/libwebp/src/enc/alpha_enc.c b/media/libwebp/src/enc/alpha_enc.c
new file mode 100644
index 0000000000..7d205586fe
--- /dev/null
+++ b/media/libwebp/src/enc/alpha_enc.c
@@ -0,0 +1,445 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Alpha-plane compression.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "src/enc/vp8i_enc.h"
+#include "src/dsp/dsp.h"
+#include "src/utils/filters_utils.h"
+#include "src/utils/quant_levels_utils.h"
+#include "src/utils/utils.h"
+#include "src/webp/format_constants.h"
+
+// -----------------------------------------------------------------------------
+// Encodes the given alpha data via specified compression method 'method'.
+// The pre-processing (quantization) is performed if 'quality' is less than 100.
+// For such cases, the encoding is lossy. The valid range is [0, 100] for
+// 'quality' and [0, 1] for 'method':
+// 'method = 0' - No compression;
+// 'method = 1' - Use lossless coder on the alpha plane only
+// 'filter' values [0, 4] correspond to prediction modes none, horizontal,
+// vertical & gradient filters. The prediction mode 4 will try all the
+// prediction modes 0 to 3 and pick the best one.
+// 'effort_level': specifies how much effort must be spent to try and reduce
+// the compressed output size. In range 0 (quick) to 6 (slow).
+//
+// 'output' corresponds to the buffer containing compressed alpha data.
+// This buffer is allocated by this method and caller should call
+// WebPSafeFree(*output) when done.
+// 'output_size' corresponds to size of this compressed alpha buffer.
+//
+// Returns 1 on successfully encoding the alpha and
+// 0 if either:
+// invalid quality or method, or
+// memory allocation for the compressed data fails.
+
+#include "src/enc/vp8li_enc.h"
+
+static int EncodeLossless(const uint8_t* const data, int width, int height,
+ int effort_level, // in [0..6] range
+ int use_quality_100, VP8LBitWriter* const bw,
+ WebPAuxStats* const stats) {
+ int ok = 0;
+ WebPConfig config;
+ WebPPicture picture;
+
+ WebPPictureInit(&picture);
+ picture.width = width;
+ picture.height = height;
+ picture.use_argb = 1;
+ picture.stats = stats;
+ if (!WebPPictureAlloc(&picture)) return 0;
+
+ // Transfer the alpha values to the green channel.
+ WebPDispatchAlphaToGreen(data, width, picture.width, picture.height,
+ picture.argb, picture.argb_stride);
+
+ WebPConfigInit(&config);
+ config.lossless = 1;
+ // Enable exact, or it would alter RGB values of transparent alpha, which is
+ // normally OK but not here since we are not encoding the input image but an
+ // internal encoding-related image containing necessary exact information in
+ // RGB channels.
+ config.exact = 1;
+ config.method = effort_level; // impact is very small
+ // Set a low default quality for encoding alpha. Ensure that Alpha quality at
+ // lower methods (3 and below) is less than the threshold for triggering
+ // costly 'BackwardReferencesTraceBackwards'.
+ // If the alpha quality is set to 100 and the method to 6, allow for a high
+ // lossless quality to trigger the cruncher.
+ config.quality =
+ (use_quality_100 && effort_level == 6) ? 100 : 8.f * effort_level;
+ assert(config.quality >= 0 && config.quality <= 100.f);
+
+ // TODO(urvang): Temporary fix to avoid generating images that trigger
+ // a decoder bug related to alpha with color cache.
+ // See: https://code.google.com/p/webp/issues/detail?id=239
+ // Need to re-enable this later.
+ ok = VP8LEncodeStream(&config, &picture, bw, /*use_cache=*/0);
+ WebPPictureFree(&picture);
+ ok = ok && !bw->error_;
+ if (!ok) {
+ VP8LBitWriterWipeOut(bw);
+ return 0;
+ }
+ return 1;
+}
+
+// -----------------------------------------------------------------------------
+
+// Small struct to hold the result of a filter mode compression attempt.
+typedef struct {
+ size_t score;
+ VP8BitWriter bw;
+ WebPAuxStats stats;
+} FilterTrial;
+
+// This function always returns an initialized 'bw' object, even upon error.
+static int EncodeAlphaInternal(const uint8_t* const data, int width, int height,
+ int method, int filter, int reduce_levels,
+ int effort_level, // in [0..6] range
+ uint8_t* const tmp_alpha,
+ FilterTrial* result) {
+ int ok = 0;
+ const uint8_t* alpha_src;
+ WebPFilterFunc filter_func;
+ uint8_t header;
+ const size_t data_size = width * height;
+ const uint8_t* output = NULL;
+ size_t output_size = 0;
+ VP8LBitWriter tmp_bw;
+
+ assert((uint64_t)data_size == (uint64_t)width * height); // as per spec
+ assert(filter >= 0 && filter < WEBP_FILTER_LAST);
+ assert(method >= ALPHA_NO_COMPRESSION);
+ assert(method <= ALPHA_LOSSLESS_COMPRESSION);
+ assert(sizeof(header) == ALPHA_HEADER_LEN);
+
+ filter_func = WebPFilters[filter];
+ if (filter_func != NULL) {
+ filter_func(data, width, height, width, tmp_alpha);
+ alpha_src = tmp_alpha;
+ } else {
+ alpha_src = data;
+ }
+
+ if (method != ALPHA_NO_COMPRESSION) {
+ ok = VP8LBitWriterInit(&tmp_bw, data_size >> 3);
+ ok = ok && EncodeLossless(alpha_src, width, height, effort_level,
+ !reduce_levels, &tmp_bw, &result->stats);
+ if (ok) {
+ output = VP8LBitWriterFinish(&tmp_bw);
+ output_size = VP8LBitWriterNumBytes(&tmp_bw);
+ if (output_size > data_size) {
+ // compressed size is larger than source! Revert to uncompressed mode.
+ method = ALPHA_NO_COMPRESSION;
+ VP8LBitWriterWipeOut(&tmp_bw);
+ }
+ } else {
+ VP8LBitWriterWipeOut(&tmp_bw);
+ memset(&result->bw, 0, sizeof(result->bw));
+ return 0;
+ }
+ }
+
+ if (method == ALPHA_NO_COMPRESSION) {
+ output = alpha_src;
+ output_size = data_size;
+ ok = 1;
+ }
+
+ // Emit final result.
+ header = method | (filter << 2);
+ if (reduce_levels) header |= ALPHA_PREPROCESSED_LEVELS << 4;
+
+ if (!VP8BitWriterInit(&result->bw, ALPHA_HEADER_LEN + output_size)) ok = 0;
+ ok = ok && VP8BitWriterAppend(&result->bw, &header, ALPHA_HEADER_LEN);
+ ok = ok && VP8BitWriterAppend(&result->bw, output, output_size);
+
+ if (method != ALPHA_NO_COMPRESSION) {
+ VP8LBitWriterWipeOut(&tmp_bw);
+ }
+ ok = ok && !result->bw.error_;
+ result->score = VP8BitWriterSize(&result->bw);
+ return ok;
+}
+
+// -----------------------------------------------------------------------------
+
+static int GetNumColors(const uint8_t* data, int width, int height,
+ int stride) {
+ int j;
+ int colors = 0;
+ uint8_t color[256] = { 0 };
+
+ for (j = 0; j < height; ++j) {
+ int i;
+ const uint8_t* const p = data + j * stride;
+ for (i = 0; i < width; ++i) {
+ color[p[i]] = 1;
+ }
+ }
+ for (j = 0; j < 256; ++j) {
+ if (color[j] > 0) ++colors;
+ }
+ return colors;
+}
+
+#define FILTER_TRY_NONE (1 << WEBP_FILTER_NONE)
+#define FILTER_TRY_ALL ((1 << WEBP_FILTER_LAST) - 1)
+
+// Given the input 'filter' option, return an OR'd bit-set of filters to try.
+static uint32_t GetFilterMap(const uint8_t* alpha, int width, int height,
+ int filter, int effort_level) {
+ uint32_t bit_map = 0U;
+ if (filter == WEBP_FILTER_FAST) {
+ // Quick estimate of the best candidate.
+ int try_filter_none = (effort_level > 3);
+ const int kMinColorsForFilterNone = 16;
+ const int kMaxColorsForFilterNone = 192;
+ const int num_colors = GetNumColors(alpha, width, height, width);
+ // For low number of colors, NONE yields better compression.
+ filter = (num_colors <= kMinColorsForFilterNone)
+ ? WEBP_FILTER_NONE
+ : WebPEstimateBestFilter(alpha, width, height, width);
+ bit_map |= 1 << filter;
+ // For large number of colors, try FILTER_NONE in addition to the best
+ // filter as well.
+ if (try_filter_none || num_colors > kMaxColorsForFilterNone) {
+ bit_map |= FILTER_TRY_NONE;
+ }
+ } else if (filter == WEBP_FILTER_NONE) {
+ bit_map = FILTER_TRY_NONE;
+ } else { // WEBP_FILTER_BEST -> try all
+ bit_map = FILTER_TRY_ALL;
+ }
+ return bit_map;
+}
+
+static void InitFilterTrial(FilterTrial* const score) {
+ score->score = (size_t)~0U;
+ VP8BitWriterInit(&score->bw, 0);
+}
+
+static int ApplyFiltersAndEncode(const uint8_t* alpha, int width, int height,
+ size_t data_size, int method, int filter,
+ int reduce_levels, int effort_level,
+ uint8_t** const output,
+ size_t* const output_size,
+ WebPAuxStats* const stats) {
+ int ok = 1;
+ FilterTrial best;
+ uint32_t try_map =
+ GetFilterMap(alpha, width, height, filter, effort_level);
+ InitFilterTrial(&best);
+
+ if (try_map != FILTER_TRY_NONE) {
+ uint8_t* filtered_alpha = (uint8_t*)WebPSafeMalloc(1ULL, data_size);
+ if (filtered_alpha == NULL) return 0;
+
+ for (filter = WEBP_FILTER_NONE; ok && try_map; ++filter, try_map >>= 1) {
+ if (try_map & 1) {
+ FilterTrial trial;
+ ok = EncodeAlphaInternal(alpha, width, height, method, filter,
+ reduce_levels, effort_level, filtered_alpha,
+ &trial);
+ if (ok && trial.score < best.score) {
+ VP8BitWriterWipeOut(&best.bw);
+ best = trial;
+ } else {
+ VP8BitWriterWipeOut(&trial.bw);
+ }
+ }
+ }
+ WebPSafeFree(filtered_alpha);
+ } else {
+ ok = EncodeAlphaInternal(alpha, width, height, method, WEBP_FILTER_NONE,
+ reduce_levels, effort_level, NULL, &best);
+ }
+ if (ok) {
+#if !defined(WEBP_DISABLE_STATS)
+ if (stats != NULL) {
+ stats->lossless_features = best.stats.lossless_features;
+ stats->histogram_bits = best.stats.histogram_bits;
+ stats->transform_bits = best.stats.transform_bits;
+ stats->cache_bits = best.stats.cache_bits;
+ stats->palette_size = best.stats.palette_size;
+ stats->lossless_size = best.stats.lossless_size;
+ stats->lossless_hdr_size = best.stats.lossless_hdr_size;
+ stats->lossless_data_size = best.stats.lossless_data_size;
+ }
+#else
+ (void)stats;
+#endif
+ *output_size = VP8BitWriterSize(&best.bw);
+ *output = VP8BitWriterBuf(&best.bw);
+ } else {
+ VP8BitWriterWipeOut(&best.bw);
+ }
+ return ok;
+}
+
+static int EncodeAlpha(VP8Encoder* const enc,
+ int quality, int method, int filter,
+ int effort_level,
+ uint8_t** const output, size_t* const output_size) {
+ const WebPPicture* const pic = enc->pic_;
+ const int width = pic->width;
+ const int height = pic->height;
+
+ uint8_t* quant_alpha = NULL;
+ const size_t data_size = width * height;
+ uint64_t sse = 0;
+ int ok = 1;
+ const int reduce_levels = (quality < 100);
+
+ // quick correctness checks
+ assert((uint64_t)data_size == (uint64_t)width * height); // as per spec
+ assert(enc != NULL && pic != NULL && pic->a != NULL);
+ assert(output != NULL && output_size != NULL);
+ assert(width > 0 && height > 0);
+ assert(pic->a_stride >= width);
+ assert(filter >= WEBP_FILTER_NONE && filter <= WEBP_FILTER_FAST);
+
+ if (quality < 0 || quality > 100) {
+ return 0;
+ }
+
+ if (method < ALPHA_NO_COMPRESSION || method > ALPHA_LOSSLESS_COMPRESSION) {
+ return 0;
+ }
+
+ if (method == ALPHA_NO_COMPRESSION) {
+ // Don't filter, as filtering will make no impact on compressed size.
+ filter = WEBP_FILTER_NONE;
+ }
+
+ quant_alpha = (uint8_t*)WebPSafeMalloc(1ULL, data_size);
+ if (quant_alpha == NULL) {
+ return 0;
+ }
+
+ // Extract alpha data (width x height) from raw_data (stride x height).
+ WebPCopyPlane(pic->a, pic->a_stride, quant_alpha, width, width, height);
+
+ if (reduce_levels) { // No Quantization required for 'quality = 100'.
+ // 16 alpha levels gives quite a low MSE w.r.t original alpha plane hence
+ // mapped to moderate quality 70. Hence Quality:[0, 70] -> Levels:[2, 16]
+ // and Quality:]70, 100] -> Levels:]16, 256].
+ const int alpha_levels = (quality <= 70) ? (2 + quality / 5)
+ : (16 + (quality - 70) * 8);
+ ok = QuantizeLevels(quant_alpha, width, height, alpha_levels, &sse);
+ }
+
+ if (ok) {
+ VP8FiltersInit();
+ ok = ApplyFiltersAndEncode(quant_alpha, width, height, data_size, method,
+ filter, reduce_levels, effort_level, output,
+ output_size, pic->stats);
+#if !defined(WEBP_DISABLE_STATS)
+ if (pic->stats != NULL) { // need stats?
+ pic->stats->coded_size += (int)(*output_size);
+ enc->sse_[3] = sse;
+ }
+#endif
+ }
+
+ WebPSafeFree(quant_alpha);
+ return ok;
+}
+
+//------------------------------------------------------------------------------
+// Main calls
+
+static int CompressAlphaJob(void* arg1, void* unused) {
+ VP8Encoder* const enc = (VP8Encoder*)arg1;
+ const WebPConfig* config = enc->config_;
+ uint8_t* alpha_data = NULL;
+ size_t alpha_size = 0;
+ const int effort_level = config->method; // maps to [0..6]
+ const WEBP_FILTER_TYPE filter =
+ (config->alpha_filtering == 0) ? WEBP_FILTER_NONE :
+ (config->alpha_filtering == 1) ? WEBP_FILTER_FAST :
+ WEBP_FILTER_BEST;
+ if (!EncodeAlpha(enc, config->alpha_quality, config->alpha_compression,
+ filter, effort_level, &alpha_data, &alpha_size)) {
+ return 0;
+ }
+ if (alpha_size != (uint32_t)alpha_size) { // Soundness check.
+ WebPSafeFree(alpha_data);
+ return 0;
+ }
+ enc->alpha_data_size_ = (uint32_t)alpha_size;
+ enc->alpha_data_ = alpha_data;
+ (void)unused;
+ return 1;
+}
+
+void VP8EncInitAlpha(VP8Encoder* const enc) {
+ WebPInitAlphaProcessing();
+ enc->has_alpha_ = WebPPictureHasTransparency(enc->pic_);
+ enc->alpha_data_ = NULL;
+ enc->alpha_data_size_ = 0;
+ if (enc->thread_level_ > 0) {
+ WebPWorker* const worker = &enc->alpha_worker_;
+ WebPGetWorkerInterface()->Init(worker);
+ worker->data1 = enc;
+ worker->data2 = NULL;
+ worker->hook = CompressAlphaJob;
+ }
+}
+
+int VP8EncStartAlpha(VP8Encoder* const enc) {
+ if (enc->has_alpha_) {
+ if (enc->thread_level_ > 0) {
+ WebPWorker* const worker = &enc->alpha_worker_;
+ // Makes sure worker is good to go.
+ if (!WebPGetWorkerInterface()->Reset(worker)) {
+ return 0;
+ }
+ WebPGetWorkerInterface()->Launch(worker);
+ return 1;
+ } else {
+ return CompressAlphaJob(enc, NULL); // just do the job right away
+ }
+ }
+ return 1;
+}
+
+int VP8EncFinishAlpha(VP8Encoder* const enc) {
+ if (enc->has_alpha_) {
+ if (enc->thread_level_ > 0) {
+ WebPWorker* const worker = &enc->alpha_worker_;
+ if (!WebPGetWorkerInterface()->Sync(worker)) return 0; // error
+ }
+ }
+ return WebPReportProgress(enc->pic_, enc->percent_ + 20, &enc->percent_);
+}
+
+int VP8EncDeleteAlpha(VP8Encoder* const enc) {
+ int ok = 1;
+ if (enc->thread_level_ > 0) {
+ WebPWorker* const worker = &enc->alpha_worker_;
+ // finish anything left in flight
+ ok = WebPGetWorkerInterface()->Sync(worker);
+ // still need to end the worker, even if !ok
+ WebPGetWorkerInterface()->End(worker);
+ }
+ WebPSafeFree(enc->alpha_data_);
+ enc->alpha_data_ = NULL;
+ enc->alpha_data_size_ = 0;
+ enc->has_alpha_ = 0;
+ return ok;
+}
diff --git a/media/libwebp/src/enc/analysis_enc.c b/media/libwebp/src/enc/analysis_enc.c
new file mode 100644
index 0000000000..a0001ac034
--- /dev/null
+++ b/media/libwebp/src/enc/analysis_enc.c
@@ -0,0 +1,479 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Macroblock analysis
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include "src/enc/vp8i_enc.h"
+#include "src/enc/cost_enc.h"
+#include "src/utils/utils.h"
+
+#define MAX_ITERS_K_MEANS 6
+
+//------------------------------------------------------------------------------
+// Smooth the segment map by replacing isolated block by the majority of its
+// neighbours.
+
+static void SmoothSegmentMap(VP8Encoder* const enc) {
+ int n, x, y;
+ const int w = enc->mb_w_;
+ const int h = enc->mb_h_;
+ const int majority_cnt_3_x_3_grid = 5;
+ uint8_t* const tmp = (uint8_t*)WebPSafeMalloc(w * h, sizeof(*tmp));
+ assert((uint64_t)(w * h) == (uint64_t)w * h); // no overflow, as per spec
+
+ if (tmp == NULL) return;
+ for (y = 1; y < h - 1; ++y) {
+ for (x = 1; x < w - 1; ++x) {
+ int cnt[NUM_MB_SEGMENTS] = { 0 };
+ const VP8MBInfo* const mb = &enc->mb_info_[x + w * y];
+ int majority_seg = mb->segment_;
+ // Check the 8 neighbouring segment values.
+ cnt[mb[-w - 1].segment_]++; // top-left
+ cnt[mb[-w + 0].segment_]++; // top
+ cnt[mb[-w + 1].segment_]++; // top-right
+ cnt[mb[ - 1].segment_]++; // left
+ cnt[mb[ + 1].segment_]++; // right
+ cnt[mb[ w - 1].segment_]++; // bottom-left
+ cnt[mb[ w + 0].segment_]++; // bottom
+ cnt[mb[ w + 1].segment_]++; // bottom-right
+ for (n = 0; n < NUM_MB_SEGMENTS; ++n) {
+ if (cnt[n] >= majority_cnt_3_x_3_grid) {
+ majority_seg = n;
+ break;
+ }
+ }
+ tmp[x + y * w] = majority_seg;
+ }
+ }
+ for (y = 1; y < h - 1; ++y) {
+ for (x = 1; x < w - 1; ++x) {
+ VP8MBInfo* const mb = &enc->mb_info_[x + w * y];
+ mb->segment_ = tmp[x + y * w];
+ }
+ }
+ WebPSafeFree(tmp);
+}
+
+//------------------------------------------------------------------------------
+// set segment susceptibility alpha_ / beta_
+
+static WEBP_INLINE int clip(int v, int m, int M) {
+ return (v < m) ? m : (v > M) ? M : v;
+}
+
+static void SetSegmentAlphas(VP8Encoder* const enc,
+ const int centers[NUM_MB_SEGMENTS],
+ int mid) {
+ const int nb = enc->segment_hdr_.num_segments_;
+ int min = centers[0], max = centers[0];
+ int n;
+
+ if (nb > 1) {
+ for (n = 0; n < nb; ++n) {
+ if (min > centers[n]) min = centers[n];
+ if (max < centers[n]) max = centers[n];
+ }
+ }
+ if (max == min) max = min + 1;
+ assert(mid <= max && mid >= min);
+ for (n = 0; n < nb; ++n) {
+ const int alpha = 255 * (centers[n] - mid) / (max - min);
+ const int beta = 255 * (centers[n] - min) / (max - min);
+ enc->dqm_[n].alpha_ = clip(alpha, -127, 127);
+ enc->dqm_[n].beta_ = clip(beta, 0, 255);
+ }
+}
+
+//------------------------------------------------------------------------------
+// Compute susceptibility based on DCT-coeff histograms:
+// the higher, the "easier" the macroblock is to compress.
+
+#define MAX_ALPHA 255 // 8b of precision for susceptibilities.
+#define ALPHA_SCALE (2 * MAX_ALPHA) // scaling factor for alpha.
+#define DEFAULT_ALPHA (-1)
+#define IS_BETTER_ALPHA(alpha, best_alpha) ((alpha) > (best_alpha))
+
+static int FinalAlphaValue(int alpha) {
+ alpha = MAX_ALPHA - alpha;
+ return clip(alpha, 0, MAX_ALPHA);
+}
+
+static int GetAlpha(const VP8Histogram* const histo) {
+ // 'alpha' will later be clipped to [0..MAX_ALPHA] range, clamping outer
+ // values which happen to be mostly noise. This leaves the maximum precision
+ // for handling the useful small values which contribute most.
+ const int max_value = histo->max_value;
+ const int last_non_zero = histo->last_non_zero;
+ const int alpha =
+ (max_value > 1) ? ALPHA_SCALE * last_non_zero / max_value : 0;
+ return alpha;
+}
+
+static void InitHistogram(VP8Histogram* const histo) {
+ histo->max_value = 0;
+ histo->last_non_zero = 1;
+}
+
+//------------------------------------------------------------------------------
+// Simplified k-Means, to assign Nb segments based on alpha-histogram
+
+static void AssignSegments(VP8Encoder* const enc,
+ const int alphas[MAX_ALPHA + 1]) {
+ // 'num_segments_' is previously validated and <= NUM_MB_SEGMENTS, but an
+ // explicit check is needed to avoid spurious warning about 'n + 1' exceeding
+ // array bounds of 'centers' with some compilers (noticed with gcc-4.9).
+ const int nb = (enc->segment_hdr_.num_segments_ < NUM_MB_SEGMENTS) ?
+ enc->segment_hdr_.num_segments_ : NUM_MB_SEGMENTS;
+ int centers[NUM_MB_SEGMENTS];
+ int weighted_average = 0;
+ int map[MAX_ALPHA + 1];
+ int a, n, k;
+ int min_a = 0, max_a = MAX_ALPHA, range_a;
+ // 'int' type is ok for histo, and won't overflow
+ int accum[NUM_MB_SEGMENTS], dist_accum[NUM_MB_SEGMENTS];
+
+ assert(nb >= 1);
+ assert(nb <= NUM_MB_SEGMENTS);
+
+ // bracket the input
+ for (n = 0; n <= MAX_ALPHA && alphas[n] == 0; ++n) {}
+ min_a = n;
+ for (n = MAX_ALPHA; n > min_a && alphas[n] == 0; --n) {}
+ max_a = n;
+ range_a = max_a - min_a;
+
+ // Spread initial centers evenly
+ for (k = 0, n = 1; k < nb; ++k, n += 2) {
+ assert(n < 2 * nb);
+ centers[k] = min_a + (n * range_a) / (2 * nb);
+ }
+
+ for (k = 0; k < MAX_ITERS_K_MEANS; ++k) { // few iters are enough
+ int total_weight;
+ int displaced;
+ // Reset stats
+ for (n = 0; n < nb; ++n) {
+ accum[n] = 0;
+ dist_accum[n] = 0;
+ }
+ // Assign nearest center for each 'a'
+ n = 0; // track the nearest center for current 'a'
+ for (a = min_a; a <= max_a; ++a) {
+ if (alphas[a]) {
+ while (n + 1 < nb && abs(a - centers[n + 1]) < abs(a - centers[n])) {
+ n++;
+ }
+ map[a] = n;
+ // accumulate contribution into best centroid
+ dist_accum[n] += a * alphas[a];
+ accum[n] += alphas[a];
+ }
+ }
+ // All point are classified. Move the centroids to the
+ // center of their respective cloud.
+ displaced = 0;
+ weighted_average = 0;
+ total_weight = 0;
+ for (n = 0; n < nb; ++n) {
+ if (accum[n]) {
+ const int new_center = (dist_accum[n] + accum[n] / 2) / accum[n];
+ displaced += abs(centers[n] - new_center);
+ centers[n] = new_center;
+ weighted_average += new_center * accum[n];
+ total_weight += accum[n];
+ }
+ }
+ weighted_average = (weighted_average + total_weight / 2) / total_weight;
+ if (displaced < 5) break; // no need to keep on looping...
+ }
+
+ // Map each original value to the closest centroid
+ for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
+ VP8MBInfo* const mb = &enc->mb_info_[n];
+ const int alpha = mb->alpha_;
+ mb->segment_ = map[alpha];
+ mb->alpha_ = centers[map[alpha]]; // for the record.
+ }
+
+ if (nb > 1) {
+ const int smooth = (enc->config_->preprocessing & 1);
+ if (smooth) SmoothSegmentMap(enc);
+ }
+
+ SetSegmentAlphas(enc, centers, weighted_average); // pick some alphas.
+}
+
+//------------------------------------------------------------------------------
+// Macroblock analysis: collect histogram for each mode, deduce the maximal
+// susceptibility and set best modes for this macroblock.
+// Segment assignment is done later.
+
+// Number of modes to inspect for alpha_ evaluation. We don't need to test all
+// the possible modes during the analysis phase: we risk falling into a local
+// optimum, or be subject to boundary effect
+#define MAX_INTRA16_MODE 2
+#define MAX_INTRA4_MODE 2
+#define MAX_UV_MODE 2
+
+static int MBAnalyzeBestIntra16Mode(VP8EncIterator* const it) {
+ const int max_mode = MAX_INTRA16_MODE;
+ int mode;
+ int best_alpha = DEFAULT_ALPHA;
+ int best_mode = 0;
+
+ VP8MakeLuma16Preds(it);
+ for (mode = 0; mode < max_mode; ++mode) {
+ VP8Histogram histo;
+ int alpha;
+
+ InitHistogram(&histo);
+ VP8CollectHistogram(it->yuv_in_ + Y_OFF_ENC,
+ it->yuv_p_ + VP8I16ModeOffsets[mode],
+ 0, 16, &histo);
+ alpha = GetAlpha(&histo);
+ if (IS_BETTER_ALPHA(alpha, best_alpha)) {
+ best_alpha = alpha;
+ best_mode = mode;
+ }
+ }
+ VP8SetIntra16Mode(it, best_mode);
+ return best_alpha;
+}
+
+static int FastMBAnalyze(VP8EncIterator* const it) {
+ // Empirical cut-off value, should be around 16 (~=block size). We use the
+ // [8-17] range and favor intra4 at high quality, intra16 for low quality.
+ const int q = (int)it->enc_->config_->quality;
+ const uint32_t kThreshold = 8 + (17 - 8) * q / 100;
+ int k;
+ uint32_t dc[16], m, m2;
+ for (k = 0; k < 16; k += 4) {
+ VP8Mean16x4(it->yuv_in_ + Y_OFF_ENC + k * BPS, &dc[k]);
+ }
+ for (m = 0, m2 = 0, k = 0; k < 16; ++k) {
+ m += dc[k];
+ m2 += dc[k] * dc[k];
+ }
+ if (kThreshold * m2 < m * m) {
+ VP8SetIntra16Mode(it, 0); // DC16
+ } else {
+ const uint8_t modes[16] = { 0 }; // DC4
+ VP8SetIntra4Mode(it, modes);
+ }
+ return 0;
+}
+
+static int MBAnalyzeBestUVMode(VP8EncIterator* const it) {
+ int best_alpha = DEFAULT_ALPHA;
+ int smallest_alpha = 0;
+ int best_mode = 0;
+ const int max_mode = MAX_UV_MODE;
+ int mode;
+
+ VP8MakeChroma8Preds(it);
+ for (mode = 0; mode < max_mode; ++mode) {
+ VP8Histogram histo;
+ int alpha;
+ InitHistogram(&histo);
+ VP8CollectHistogram(it->yuv_in_ + U_OFF_ENC,
+ it->yuv_p_ + VP8UVModeOffsets[mode],
+ 16, 16 + 4 + 4, &histo);
+ alpha = GetAlpha(&histo);
+ if (IS_BETTER_ALPHA(alpha, best_alpha)) {
+ best_alpha = alpha;
+ }
+ // The best prediction mode tends to be the one with the smallest alpha.
+ if (mode == 0 || alpha < smallest_alpha) {
+ smallest_alpha = alpha;
+ best_mode = mode;
+ }
+ }
+ VP8SetIntraUVMode(it, best_mode);
+ return best_alpha;
+}
+
+static void MBAnalyze(VP8EncIterator* const it,
+ int alphas[MAX_ALPHA + 1],
+ int* const alpha, int* const uv_alpha) {
+ const VP8Encoder* const enc = it->enc_;
+ int best_alpha, best_uv_alpha;
+
+ VP8SetIntra16Mode(it, 0); // default: Intra16, DC_PRED
+ VP8SetSkip(it, 0); // not skipped
+ VP8SetSegment(it, 0); // default segment, spec-wise.
+
+ if (enc->method_ <= 1) {
+ best_alpha = FastMBAnalyze(it);
+ } else {
+ best_alpha = MBAnalyzeBestIntra16Mode(it);
+ }
+ best_uv_alpha = MBAnalyzeBestUVMode(it);
+
+ // Final susceptibility mix
+ best_alpha = (3 * best_alpha + best_uv_alpha + 2) >> 2;
+ best_alpha = FinalAlphaValue(best_alpha);
+ alphas[best_alpha]++;
+ it->mb_->alpha_ = best_alpha; // for later remapping.
+
+ // Accumulate for later complexity analysis.
+ *alpha += best_alpha; // mixed susceptibility (not just luma)
+ *uv_alpha += best_uv_alpha;
+}
+
+static void DefaultMBInfo(VP8MBInfo* const mb) {
+ mb->type_ = 1; // I16x16
+ mb->uv_mode_ = 0;
+ mb->skip_ = 0; // not skipped
+ mb->segment_ = 0; // default segment
+ mb->alpha_ = 0;
+}
+
+//------------------------------------------------------------------------------
+// Main analysis loop:
+// Collect all susceptibilities for each macroblock and record their
+// distribution in alphas[]. Segments is assigned a-posteriori, based on
+// this histogram.
+// We also pick an intra16 prediction mode, which shouldn't be considered
+// final except for fast-encode settings. We can also pick some intra4 modes
+// and decide intra4/intra16, but that's usually almost always a bad choice at
+// this stage.
+
+static void ResetAllMBInfo(VP8Encoder* const enc) {
+ int n;
+ for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
+ DefaultMBInfo(&enc->mb_info_[n]);
+ }
+ // Default susceptibilities.
+ enc->dqm_[0].alpha_ = 0;
+ enc->dqm_[0].beta_ = 0;
+ // Note: we can't compute this alpha_ / uv_alpha_ -> set to default value.
+ enc->alpha_ = 0;
+ enc->uv_alpha_ = 0;
+ WebPReportProgress(enc->pic_, enc->percent_ + 20, &enc->percent_);
+}
+
+// struct used to collect job result
+typedef struct {
+ WebPWorker worker;
+ int alphas[MAX_ALPHA + 1];
+ int alpha, uv_alpha;
+ VP8EncIterator it;
+ int delta_progress;
+} SegmentJob;
+
+// main work call
+static int DoSegmentsJob(void* arg1, void* arg2) {
+ SegmentJob* const job = (SegmentJob*)arg1;
+ VP8EncIterator* const it = (VP8EncIterator*)arg2;
+ int ok = 1;
+ if (!VP8IteratorIsDone(it)) {
+ uint8_t tmp[32 + WEBP_ALIGN_CST];
+ uint8_t* const scratch = (uint8_t*)WEBP_ALIGN(tmp);
+ do {
+ // Let's pretend we have perfect lossless reconstruction.
+ VP8IteratorImport(it, scratch);
+ MBAnalyze(it, job->alphas, &job->alpha, &job->uv_alpha);
+ ok = VP8IteratorProgress(it, job->delta_progress);
+ } while (ok && VP8IteratorNext(it));
+ }
+ return ok;
+}
+
+#ifdef WEBP_USE_THREAD
+static void MergeJobs(const SegmentJob* const src, SegmentJob* const dst) {
+ int i;
+ for (i = 0; i <= MAX_ALPHA; ++i) dst->alphas[i] += src->alphas[i];
+ dst->alpha += src->alpha;
+ dst->uv_alpha += src->uv_alpha;
+}
+#endif
+
+// initialize the job struct with some tasks to perform
+static void InitSegmentJob(VP8Encoder* const enc, SegmentJob* const job,
+ int start_row, int end_row) {
+ WebPGetWorkerInterface()->Init(&job->worker);
+ job->worker.data1 = job;
+ job->worker.data2 = &job->it;
+ job->worker.hook = DoSegmentsJob;
+ VP8IteratorInit(enc, &job->it);
+ VP8IteratorSetRow(&job->it, start_row);
+ VP8IteratorSetCountDown(&job->it, (end_row - start_row) * enc->mb_w_);
+ memset(job->alphas, 0, sizeof(job->alphas));
+ job->alpha = 0;
+ job->uv_alpha = 0;
+ // only one of both jobs can record the progress, since we don't
+ // expect the user's hook to be multi-thread safe
+ job->delta_progress = (start_row == 0) ? 20 : 0;
+}
+
+// main entry point
+int VP8EncAnalyze(VP8Encoder* const enc) {
+ int ok = 1;
+ const int do_segments =
+ enc->config_->emulate_jpeg_size || // We need the complexity evaluation.
+ (enc->segment_hdr_.num_segments_ > 1) ||
+ (enc->method_ <= 1); // for method 0 - 1, we need preds_[] to be filled.
+ if (do_segments) {
+ const int last_row = enc->mb_h_;
+ const int total_mb = last_row * enc->mb_w_;
+#ifdef WEBP_USE_THREAD
+ // We give a little more than a half work to the main thread.
+ const int split_row = (9 * last_row + 15) >> 4;
+ const int kMinSplitRow = 2; // minimal rows needed for mt to be worth it
+ const int do_mt = (enc->thread_level_ > 0) && (split_row >= kMinSplitRow);
+#else
+ const int do_mt = 0;
+#endif
+ const WebPWorkerInterface* const worker_interface =
+ WebPGetWorkerInterface();
+ SegmentJob main_job;
+ if (do_mt) {
+#ifdef WEBP_USE_THREAD
+ SegmentJob side_job;
+ // Note the use of '&' instead of '&&' because we must call the functions
+ // no matter what.
+ InitSegmentJob(enc, &main_job, 0, split_row);
+ InitSegmentJob(enc, &side_job, split_row, last_row);
+ // we don't need to call Reset() on main_job.worker, since we're calling
+ // WebPWorkerExecute() on it
+ ok &= worker_interface->Reset(&side_job.worker);
+ // launch the two jobs in parallel
+ if (ok) {
+ worker_interface->Launch(&side_job.worker);
+ worker_interface->Execute(&main_job.worker);
+ ok &= worker_interface->Sync(&side_job.worker);
+ ok &= worker_interface->Sync(&main_job.worker);
+ }
+ worker_interface->End(&side_job.worker);
+ if (ok) MergeJobs(&side_job, &main_job); // merge results together
+#endif // WEBP_USE_THREAD
+ } else {
+ // Even for single-thread case, we use the generic Worker tools.
+ InitSegmentJob(enc, &main_job, 0, last_row);
+ worker_interface->Execute(&main_job.worker);
+ ok &= worker_interface->Sync(&main_job.worker);
+ }
+ worker_interface->End(&main_job.worker);
+ if (ok) {
+ enc->alpha_ = main_job.alpha / total_mb;
+ enc->uv_alpha_ = main_job.uv_alpha / total_mb;
+ AssignSegments(enc, main_job.alphas);
+ }
+ } else { // Use only one default segment.
+ ResetAllMBInfo(enc);
+ }
+ return ok;
+}
+
diff --git a/media/libwebp/src/enc/backward_references_cost_enc.c b/media/libwebp/src/enc/backward_references_cost_enc.c
new file mode 100644
index 0000000000..6968ef3c9f
--- /dev/null
+++ b/media/libwebp/src/enc/backward_references_cost_enc.c
@@ -0,0 +1,795 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Improves a given set of backward references by analyzing its bit cost.
+// The algorithm is similar to the Zopfli compression algorithm but tailored to
+// images.
+//
+// Author: Vincent Rabaud (vrabaud@google.com)
+//
+
+#include <assert.h>
+#include <float.h>
+
+#include "src/dsp/lossless_common.h"
+#include "src/enc/backward_references_enc.h"
+#include "src/enc/histogram_enc.h"
+#include "src/utils/color_cache_utils.h"
+#include "src/utils/utils.h"
+
+#define VALUES_IN_BYTE 256
+
+extern void VP8LClearBackwardRefs(VP8LBackwardRefs* const refs);
+extern int VP8LDistanceToPlaneCode(int xsize, int dist);
+extern void VP8LBackwardRefsCursorAdd(VP8LBackwardRefs* const refs,
+ const PixOrCopy v);
+
+typedef struct {
+ float alpha_[VALUES_IN_BYTE];
+ float red_[VALUES_IN_BYTE];
+ float blue_[VALUES_IN_BYTE];
+ float distance_[NUM_DISTANCE_CODES];
+ float* literal_;
+} CostModel;
+
+static void ConvertPopulationCountTableToBitEstimates(
+ int num_symbols, const uint32_t population_counts[], float output[]) {
+ uint32_t sum = 0;
+ int nonzeros = 0;
+ int i;
+ for (i = 0; i < num_symbols; ++i) {
+ sum += population_counts[i];
+ if (population_counts[i] > 0) {
+ ++nonzeros;
+ }
+ }
+ if (nonzeros <= 1) {
+ memset(output, 0, num_symbols * sizeof(*output));
+ } else {
+ const float logsum = VP8LFastLog2(sum);
+ for (i = 0; i < num_symbols; ++i) {
+ output[i] = logsum - VP8LFastLog2(population_counts[i]);
+ }
+ }
+}
+
+static int CostModelBuild(CostModel* const m, int xsize, int cache_bits,
+ const VP8LBackwardRefs* const refs) {
+ int ok = 0;
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ VP8LHistogram* const histo = VP8LAllocateHistogram(cache_bits);
+ if (histo == NULL) goto Error;
+
+ // The following code is similar to VP8LHistogramCreate but converts the
+ // distance to plane code.
+ VP8LHistogramInit(histo, cache_bits, /*init_arrays=*/ 1);
+ while (VP8LRefsCursorOk(&c)) {
+ VP8LHistogramAddSinglePixOrCopy(histo, c.cur_pos, VP8LDistanceToPlaneCode,
+ xsize);
+ VP8LRefsCursorNext(&c);
+ }
+
+ ConvertPopulationCountTableToBitEstimates(
+ VP8LHistogramNumCodes(histo->palette_code_bits_), histo->literal_,
+ m->literal_);
+ ConvertPopulationCountTableToBitEstimates(
+ VALUES_IN_BYTE, histo->red_, m->red_);
+ ConvertPopulationCountTableToBitEstimates(
+ VALUES_IN_BYTE, histo->blue_, m->blue_);
+ ConvertPopulationCountTableToBitEstimates(
+ VALUES_IN_BYTE, histo->alpha_, m->alpha_);
+ ConvertPopulationCountTableToBitEstimates(
+ NUM_DISTANCE_CODES, histo->distance_, m->distance_);
+ ok = 1;
+
+ Error:
+ VP8LFreeHistogram(histo);
+ return ok;
+}
+
+static WEBP_INLINE float GetLiteralCost(const CostModel* const m, uint32_t v) {
+ return m->alpha_[v >> 24] +
+ m->red_[(v >> 16) & 0xff] +
+ m->literal_[(v >> 8) & 0xff] +
+ m->blue_[v & 0xff];
+}
+
+static WEBP_INLINE float GetCacheCost(const CostModel* const m, uint32_t idx) {
+ const int literal_idx = VALUES_IN_BYTE + NUM_LENGTH_CODES + idx;
+ return m->literal_[literal_idx];
+}
+
+static WEBP_INLINE float GetLengthCost(const CostModel* const m,
+ uint32_t length) {
+ int code, extra_bits;
+ VP8LPrefixEncodeBits(length, &code, &extra_bits);
+ return m->literal_[VALUES_IN_BYTE + code] + extra_bits;
+}
+
+static WEBP_INLINE float GetDistanceCost(const CostModel* const m,
+ uint32_t distance) {
+ int code, extra_bits;
+ VP8LPrefixEncodeBits(distance, &code, &extra_bits);
+ return m->distance_[code] + extra_bits;
+}
+
+static WEBP_INLINE void AddSingleLiteralWithCostModel(
+ const uint32_t* const argb, VP8LColorCache* const hashers,
+ const CostModel* const cost_model, int idx, int use_color_cache,
+ float prev_cost, float* const cost, uint16_t* const dist_array) {
+ float cost_val = prev_cost;
+ const uint32_t color = argb[idx];
+ const int ix = use_color_cache ? VP8LColorCacheContains(hashers, color) : -1;
+ if (ix >= 0) {
+ // use_color_cache is true and hashers contains color
+ const float mul0 = 0.68f;
+ cost_val += GetCacheCost(cost_model, ix) * mul0;
+ } else {
+ const float mul1 = 0.82f;
+ if (use_color_cache) VP8LColorCacheInsert(hashers, color);
+ cost_val += GetLiteralCost(cost_model, color) * mul1;
+ }
+ if (cost[idx] > cost_val) {
+ cost[idx] = cost_val;
+ dist_array[idx] = 1; // only one is inserted.
+ }
+}
+
+// -----------------------------------------------------------------------------
+// CostManager and interval handling
+
+// Empirical value to avoid high memory consumption but good for performance.
+#define COST_CACHE_INTERVAL_SIZE_MAX 500
+
+// To perform backward reference every pixel at index index_ is considered and
+// the cost for the MAX_LENGTH following pixels computed. Those following pixels
+// at index index_ + k (k from 0 to MAX_LENGTH) have a cost of:
+// cost_ = distance cost at index + GetLengthCost(cost_model, k)
+// and the minimum value is kept. GetLengthCost(cost_model, k) is cached in an
+// array of size MAX_LENGTH.
+// Instead of performing MAX_LENGTH comparisons per pixel, we keep track of the
+// minimal values using intervals of constant cost.
+// An interval is defined by the index_ of the pixel that generated it and
+// is only useful in a range of indices from start_ to end_ (exclusive), i.e.
+// it contains the minimum value for pixels between start_ and end_.
+// Intervals are stored in a linked list and ordered by start_. When a new
+// interval has a better value, old intervals are split or removed. There are
+// therefore no overlapping intervals.
+typedef struct CostInterval CostInterval;
+struct CostInterval {
+ float cost_;
+ int start_;
+ int end_;
+ int index_;
+ CostInterval* previous_;
+ CostInterval* next_;
+};
+
+// The GetLengthCost(cost_model, k) are cached in a CostCacheInterval.
+typedef struct {
+ float cost_;
+ int start_;
+ int end_; // Exclusive.
+} CostCacheInterval;
+
+// This structure is in charge of managing intervals and costs.
+// It caches the different CostCacheInterval, caches the different
+// GetLengthCost(cost_model, k) in cost_cache_ and the CostInterval's (whose
+// count_ is limited by COST_CACHE_INTERVAL_SIZE_MAX).
+#define COST_MANAGER_MAX_FREE_LIST 10
+typedef struct {
+ CostInterval* head_;
+ int count_; // The number of stored intervals.
+ CostCacheInterval* cache_intervals_;
+ size_t cache_intervals_size_;
+ float cost_cache_[MAX_LENGTH]; // Contains the GetLengthCost(cost_model, k).
+ float* costs_;
+ uint16_t* dist_array_;
+ // Most of the time, we only need few intervals -> use a free-list, to avoid
+ // fragmentation with small allocs in most common cases.
+ CostInterval intervals_[COST_MANAGER_MAX_FREE_LIST];
+ CostInterval* free_intervals_;
+ // These are regularly malloc'd remains. This list can't grow larger than than
+ // size COST_CACHE_INTERVAL_SIZE_MAX - COST_MANAGER_MAX_FREE_LIST, note.
+ CostInterval* recycled_intervals_;
+} CostManager;
+
+static void CostIntervalAddToFreeList(CostManager* const manager,
+ CostInterval* const interval) {
+ interval->next_ = manager->free_intervals_;
+ manager->free_intervals_ = interval;
+}
+
+static int CostIntervalIsInFreeList(const CostManager* const manager,
+ const CostInterval* const interval) {
+ return (interval >= &manager->intervals_[0] &&
+ interval <= &manager->intervals_[COST_MANAGER_MAX_FREE_LIST - 1]);
+}
+
+static void CostManagerInitFreeList(CostManager* const manager) {
+ int i;
+ manager->free_intervals_ = NULL;
+ for (i = 0; i < COST_MANAGER_MAX_FREE_LIST; ++i) {
+ CostIntervalAddToFreeList(manager, &manager->intervals_[i]);
+ }
+}
+
+static void DeleteIntervalList(CostManager* const manager,
+ const CostInterval* interval) {
+ while (interval != NULL) {
+ const CostInterval* const next = interval->next_;
+ if (!CostIntervalIsInFreeList(manager, interval)) {
+ WebPSafeFree((void*)interval);
+ } // else: do nothing
+ interval = next;
+ }
+}
+
+static void CostManagerClear(CostManager* const manager) {
+ if (manager == NULL) return;
+
+ WebPSafeFree(manager->costs_);
+ WebPSafeFree(manager->cache_intervals_);
+
+ // Clear the interval lists.
+ DeleteIntervalList(manager, manager->head_);
+ manager->head_ = NULL;
+ DeleteIntervalList(manager, manager->recycled_intervals_);
+ manager->recycled_intervals_ = NULL;
+
+ // Reset pointers, count_ and cache_intervals_size_.
+ memset(manager, 0, sizeof(*manager));
+ CostManagerInitFreeList(manager);
+}
+
+static int CostManagerInit(CostManager* const manager,
+ uint16_t* const dist_array, int pix_count,
+ const CostModel* const cost_model) {
+ int i;
+ const int cost_cache_size = (pix_count > MAX_LENGTH) ? MAX_LENGTH : pix_count;
+
+ manager->costs_ = NULL;
+ manager->cache_intervals_ = NULL;
+ manager->head_ = NULL;
+ manager->recycled_intervals_ = NULL;
+ manager->count_ = 0;
+ manager->dist_array_ = dist_array;
+ CostManagerInitFreeList(manager);
+
+ // Fill in the cost_cache_.
+ // Has to be done in two passes due to a GCC bug on i686
+ // related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=323
+ for (i = 0; i < cost_cache_size; ++i) {
+ manager->cost_cache_[i] = GetLengthCost(cost_model, i);
+ }
+ manager->cache_intervals_size_ = 1;
+ for (i = 1; i < cost_cache_size; ++i) {
+ // Get the number of bound intervals.
+ if (manager->cost_cache_[i] != manager->cost_cache_[i - 1]) {
+ ++manager->cache_intervals_size_;
+ }
+ }
+
+ // With the current cost model, we usually have below 20 intervals.
+ // The worst case scenario with a cost model would be if every length has a
+ // different cost, hence MAX_LENGTH but that is impossible with the current
+ // implementation that spirals around a pixel.
+ assert(manager->cache_intervals_size_ <= MAX_LENGTH);
+ manager->cache_intervals_ = (CostCacheInterval*)WebPSafeMalloc(
+ manager->cache_intervals_size_, sizeof(*manager->cache_intervals_));
+ if (manager->cache_intervals_ == NULL) {
+ CostManagerClear(manager);
+ return 0;
+ }
+
+ // Fill in the cache_intervals_.
+ {
+ CostCacheInterval* cur = manager->cache_intervals_;
+
+ // Consecutive values in cost_cache_ are compared and if a big enough
+ // difference is found, a new interval is created and bounded.
+ cur->start_ = 0;
+ cur->end_ = 1;
+ cur->cost_ = manager->cost_cache_[0];
+ for (i = 1; i < cost_cache_size; ++i) {
+ const float cost_val = manager->cost_cache_[i];
+ if (cost_val != cur->cost_) {
+ ++cur;
+ // Initialize an interval.
+ cur->start_ = i;
+ cur->cost_ = cost_val;
+ }
+ cur->end_ = i + 1;
+ }
+ assert((size_t)(cur - manager->cache_intervals_) + 1 ==
+ manager->cache_intervals_size_);
+ }
+
+ manager->costs_ = (float*)WebPSafeMalloc(pix_count, sizeof(*manager->costs_));
+ if (manager->costs_ == NULL) {
+ CostManagerClear(manager);
+ return 0;
+ }
+ // Set the initial costs_ high for every pixel as we will keep the minimum.
+ for (i = 0; i < pix_count; ++i) manager->costs_[i] = FLT_MAX;
+
+ return 1;
+}
+
+// Given the cost and the position that define an interval, update the cost at
+// pixel 'i' if it is smaller than the previously computed value.
+static WEBP_INLINE void UpdateCost(CostManager* const manager, int i,
+ int position, float cost) {
+ const int k = i - position;
+ assert(k >= 0 && k < MAX_LENGTH);
+
+ if (manager->costs_[i] > cost) {
+ manager->costs_[i] = cost;
+ manager->dist_array_[i] = k + 1;
+ }
+}
+
+// Given the cost and the position that define an interval, update the cost for
+// all the pixels between 'start' and 'end' excluded.
+static WEBP_INLINE void UpdateCostPerInterval(CostManager* const manager,
+ int start, int end, int position,
+ float cost) {
+ int i;
+ for (i = start; i < end; ++i) UpdateCost(manager, i, position, cost);
+}
+
+// Given two intervals, make 'prev' be the previous one of 'next' in 'manager'.
+static WEBP_INLINE void ConnectIntervals(CostManager* const manager,
+ CostInterval* const prev,
+ CostInterval* const next) {
+ if (prev != NULL) {
+ prev->next_ = next;
+ } else {
+ manager->head_ = next;
+ }
+
+ if (next != NULL) next->previous_ = prev;
+}
+
+// Pop an interval in the manager.
+static WEBP_INLINE void PopInterval(CostManager* const manager,
+ CostInterval* const interval) {
+ if (interval == NULL) return;
+
+ ConnectIntervals(manager, interval->previous_, interval->next_);
+ if (CostIntervalIsInFreeList(manager, interval)) {
+ CostIntervalAddToFreeList(manager, interval);
+ } else { // recycle regularly malloc'd intervals too
+ interval->next_ = manager->recycled_intervals_;
+ manager->recycled_intervals_ = interval;
+ }
+ --manager->count_;
+ assert(manager->count_ >= 0);
+}
+
+// Update the cost at index i by going over all the stored intervals that
+// overlap with i.
+// If 'do_clean_intervals' is set to something different than 0, intervals that
+// end before 'i' will be popped.
+static WEBP_INLINE void UpdateCostAtIndex(CostManager* const manager, int i,
+ int do_clean_intervals) {
+ CostInterval* current = manager->head_;
+
+ while (current != NULL && current->start_ <= i) {
+ CostInterval* const next = current->next_;
+ if (current->end_ <= i) {
+ if (do_clean_intervals) {
+ // We have an outdated interval, remove it.
+ PopInterval(manager, current);
+ }
+ } else {
+ UpdateCost(manager, i, current->index_, current->cost_);
+ }
+ current = next;
+ }
+}
+
+// Given a current orphan interval and its previous interval, before
+// it was orphaned (which can be NULL), set it at the right place in the list
+// of intervals using the start_ ordering and the previous interval as a hint.
+static WEBP_INLINE void PositionOrphanInterval(CostManager* const manager,
+ CostInterval* const current,
+ CostInterval* previous) {
+ assert(current != NULL);
+
+ if (previous == NULL) previous = manager->head_;
+ while (previous != NULL && current->start_ < previous->start_) {
+ previous = previous->previous_;
+ }
+ while (previous != NULL && previous->next_ != NULL &&
+ previous->next_->start_ < current->start_) {
+ previous = previous->next_;
+ }
+
+ if (previous != NULL) {
+ ConnectIntervals(manager, current, previous->next_);
+ } else {
+ ConnectIntervals(manager, current, manager->head_);
+ }
+ ConnectIntervals(manager, previous, current);
+}
+
+// Insert an interval in the list contained in the manager by starting at
+// interval_in as a hint. The intervals are sorted by start_ value.
+static WEBP_INLINE void InsertInterval(CostManager* const manager,
+ CostInterval* const interval_in,
+ float cost, int position, int start,
+ int end) {
+ CostInterval* interval_new;
+
+ if (start >= end) return;
+ if (manager->count_ >= COST_CACHE_INTERVAL_SIZE_MAX) {
+ // Serialize the interval if we cannot store it.
+ UpdateCostPerInterval(manager, start, end, position, cost);
+ return;
+ }
+ if (manager->free_intervals_ != NULL) {
+ interval_new = manager->free_intervals_;
+ manager->free_intervals_ = interval_new->next_;
+ } else if (manager->recycled_intervals_ != NULL) {
+ interval_new = manager->recycled_intervals_;
+ manager->recycled_intervals_ = interval_new->next_;
+ } else { // malloc for good
+ interval_new = (CostInterval*)WebPSafeMalloc(1, sizeof(*interval_new));
+ if (interval_new == NULL) {
+ // Write down the interval if we cannot create it.
+ UpdateCostPerInterval(manager, start, end, position, cost);
+ return;
+ }
+ }
+
+ interval_new->cost_ = cost;
+ interval_new->index_ = position;
+ interval_new->start_ = start;
+ interval_new->end_ = end;
+ PositionOrphanInterval(manager, interval_new, interval_in);
+
+ ++manager->count_;
+}
+
+// Given a new cost interval defined by its start at position, its length value
+// and distance_cost, add its contributions to the previous intervals and costs.
+// If handling the interval or one of its subintervals becomes to heavy, its
+// contribution is added to the costs right away.
+static WEBP_INLINE void PushInterval(CostManager* const manager,
+ float distance_cost, int position,
+ int len) {
+ size_t i;
+ CostInterval* interval = manager->head_;
+ CostInterval* interval_next;
+ const CostCacheInterval* const cost_cache_intervals =
+ manager->cache_intervals_;
+ // If the interval is small enough, no need to deal with the heavy
+ // interval logic, just serialize it right away. This constant is empirical.
+ const int kSkipDistance = 10;
+
+ if (len < kSkipDistance) {
+ int j;
+ for (j = position; j < position + len; ++j) {
+ const int k = j - position;
+ float cost_tmp;
+ assert(k >= 0 && k < MAX_LENGTH);
+ cost_tmp = distance_cost + manager->cost_cache_[k];
+
+ if (manager->costs_[j] > cost_tmp) {
+ manager->costs_[j] = cost_tmp;
+ manager->dist_array_[j] = k + 1;
+ }
+ }
+ return;
+ }
+
+ for (i = 0; i < manager->cache_intervals_size_ &&
+ cost_cache_intervals[i].start_ < len;
+ ++i) {
+ // Define the intersection of the ith interval with the new one.
+ int start = position + cost_cache_intervals[i].start_;
+ const int end = position + (cost_cache_intervals[i].end_ > len
+ ? len
+ : cost_cache_intervals[i].end_);
+ const float cost = distance_cost + cost_cache_intervals[i].cost_;
+
+ for (; interval != NULL && interval->start_ < end;
+ interval = interval_next) {
+ interval_next = interval->next_;
+
+ // Make sure we have some overlap
+ if (start >= interval->end_) continue;
+
+ if (cost >= interval->cost_) {
+ // When intervals are represented, the lower, the better.
+ // [**********************************************************[
+ // start end
+ // [----------------------------------[
+ // interval->start_ interval->end_
+ // If we are worse than what we already have, add whatever we have so
+ // far up to interval.
+ const int start_new = interval->end_;
+ InsertInterval(manager, interval, cost, position, start,
+ interval->start_);
+ start = start_new;
+ if (start >= end) break;
+ continue;
+ }
+
+ if (start <= interval->start_) {
+ if (interval->end_ <= end) {
+ // [----------------------------------[
+ // interval->start_ interval->end_
+ // [**************************************************************[
+ // start end
+ // We can safely remove the old interval as it is fully included.
+ PopInterval(manager, interval);
+ } else {
+ // [------------------------------------[
+ // interval->start_ interval->end_
+ // [*****************************[
+ // start end
+ interval->start_ = end;
+ break;
+ }
+ } else {
+ if (end < interval->end_) {
+ // [--------------------------------------------------------------[
+ // interval->start_ interval->end_
+ // [*****************************[
+ // start end
+ // We have to split the old interval as it fully contains the new one.
+ const int end_original = interval->end_;
+ interval->end_ = start;
+ InsertInterval(manager, interval, interval->cost_, interval->index_,
+ end, end_original);
+ interval = interval->next_;
+ break;
+ } else {
+ // [------------------------------------[
+ // interval->start_ interval->end_
+ // [*****************************[
+ // start end
+ interval->end_ = start;
+ }
+ }
+ }
+ // Insert the remaining interval from start to end.
+ InsertInterval(manager, interval, cost, position, start, end);
+ }
+}
+
+static int BackwardReferencesHashChainDistanceOnly(
+ int xsize, int ysize, const uint32_t* const argb, int cache_bits,
+ const VP8LHashChain* const hash_chain, const VP8LBackwardRefs* const refs,
+ uint16_t* const dist_array) {
+ int i;
+ int ok = 0;
+ int cc_init = 0;
+ const int pix_count = xsize * ysize;
+ const int use_color_cache = (cache_bits > 0);
+ const size_t literal_array_size =
+ sizeof(float) * (VP8LHistogramNumCodes(cache_bits));
+ const size_t cost_model_size = sizeof(CostModel) + literal_array_size;
+ CostModel* const cost_model =
+ (CostModel*)WebPSafeCalloc(1ULL, cost_model_size);
+ VP8LColorCache hashers;
+ CostManager* cost_manager =
+ (CostManager*)WebPSafeCalloc(1ULL, sizeof(*cost_manager));
+ int offset_prev = -1, len_prev = -1;
+ float offset_cost = -1.f;
+ int first_offset_is_constant = -1; // initialized with 'impossible' value
+ int reach = 0;
+
+ if (cost_model == NULL || cost_manager == NULL) goto Error;
+
+ cost_model->literal_ = (float*)(cost_model + 1);
+ if (use_color_cache) {
+ cc_init = VP8LColorCacheInit(&hashers, cache_bits);
+ if (!cc_init) goto Error;
+ }
+
+ if (!CostModelBuild(cost_model, xsize, cache_bits, refs)) {
+ goto Error;
+ }
+
+ if (!CostManagerInit(cost_manager, dist_array, pix_count, cost_model)) {
+ goto Error;
+ }
+
+ // We loop one pixel at a time, but store all currently best points to
+ // non-processed locations from this point.
+ dist_array[0] = 0;
+ // Add first pixel as literal.
+ AddSingleLiteralWithCostModel(argb, &hashers, cost_model, 0, use_color_cache,
+ 0.f, cost_manager->costs_, dist_array);
+
+ for (i = 1; i < pix_count; ++i) {
+ const float prev_cost = cost_manager->costs_[i - 1];
+ int offset, len;
+ VP8LHashChainFindCopy(hash_chain, i, &offset, &len);
+
+ // Try adding the pixel as a literal.
+ AddSingleLiteralWithCostModel(argb, &hashers, cost_model, i,
+ use_color_cache, prev_cost,
+ cost_manager->costs_, dist_array);
+
+ // If we are dealing with a non-literal.
+ if (len >= 2) {
+ if (offset != offset_prev) {
+ const int code = VP8LDistanceToPlaneCode(xsize, offset);
+ offset_cost = GetDistanceCost(cost_model, code);
+ first_offset_is_constant = 1;
+ PushInterval(cost_manager, prev_cost + offset_cost, i, len);
+ } else {
+ assert(offset_cost >= 0);
+ assert(len_prev >= 0);
+ assert(first_offset_is_constant == 0 || first_offset_is_constant == 1);
+ // Instead of considering all contributions from a pixel i by calling:
+ // PushInterval(cost_manager, prev_cost + offset_cost, i, len);
+ // we optimize these contributions in case offset_cost stays the same
+ // for consecutive pixels. This describes a set of pixels similar to a
+ // previous set (e.g. constant color regions).
+ if (first_offset_is_constant) {
+ reach = i - 1 + len_prev - 1;
+ first_offset_is_constant = 0;
+ }
+
+ if (i + len - 1 > reach) {
+ // We can only be go further with the same offset if the previous
+ // length was maxed, hence len_prev == len == MAX_LENGTH.
+ // TODO(vrabaud), bump i to the end right away (insert cache and
+ // update cost).
+ // TODO(vrabaud), check if one of the points in between does not have
+ // a lower cost.
+ // Already consider the pixel at "reach" to add intervals that are
+ // better than whatever we add.
+ int offset_j, len_j = 0;
+ int j;
+ assert(len == MAX_LENGTH || len == pix_count - i);
+ // Figure out the last consecutive pixel within [i, reach + 1] with
+ // the same offset.
+ for (j = i; j <= reach; ++j) {
+ VP8LHashChainFindCopy(hash_chain, j + 1, &offset_j, &len_j);
+ if (offset_j != offset) {
+ VP8LHashChainFindCopy(hash_chain, j, &offset_j, &len_j);
+ break;
+ }
+ }
+ // Update the cost at j - 1 and j.
+ UpdateCostAtIndex(cost_manager, j - 1, 0);
+ UpdateCostAtIndex(cost_manager, j, 0);
+
+ PushInterval(cost_manager, cost_manager->costs_[j - 1] + offset_cost,
+ j, len_j);
+ reach = j + len_j - 1;
+ }
+ }
+ }
+
+ UpdateCostAtIndex(cost_manager, i, 1);
+ offset_prev = offset;
+ len_prev = len;
+ }
+
+ ok = !refs->error_;
+ Error:
+ if (cc_init) VP8LColorCacheClear(&hashers);
+ CostManagerClear(cost_manager);
+ WebPSafeFree(cost_model);
+ WebPSafeFree(cost_manager);
+ return ok;
+}
+
+// We pack the path at the end of *dist_array and return
+// a pointer to this part of the array. Example:
+// dist_array = [1x2xx3x2] => packed [1x2x1232], chosen_path = [1232]
+static void TraceBackwards(uint16_t* const dist_array,
+ int dist_array_size,
+ uint16_t** const chosen_path,
+ int* const chosen_path_size) {
+ uint16_t* path = dist_array + dist_array_size;
+ uint16_t* cur = dist_array + dist_array_size - 1;
+ while (cur >= dist_array) {
+ const int k = *cur;
+ --path;
+ *path = k;
+ cur -= k;
+ }
+ *chosen_path = path;
+ *chosen_path_size = (int)(dist_array + dist_array_size - path);
+}
+
+static int BackwardReferencesHashChainFollowChosenPath(
+ const uint32_t* const argb, int cache_bits,
+ const uint16_t* const chosen_path, int chosen_path_size,
+ const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs) {
+ const int use_color_cache = (cache_bits > 0);
+ int ix;
+ int i = 0;
+ int ok = 0;
+ int cc_init = 0;
+ VP8LColorCache hashers;
+
+ if (use_color_cache) {
+ cc_init = VP8LColorCacheInit(&hashers, cache_bits);
+ if (!cc_init) goto Error;
+ }
+
+ VP8LClearBackwardRefs(refs);
+ for (ix = 0; ix < chosen_path_size; ++ix) {
+ const int len = chosen_path[ix];
+ if (len != 1) {
+ int k;
+ const int offset = VP8LHashChainFindOffset(hash_chain, i);
+ VP8LBackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(offset, len));
+ if (use_color_cache) {
+ for (k = 0; k < len; ++k) {
+ VP8LColorCacheInsert(&hashers, argb[i + k]);
+ }
+ }
+ i += len;
+ } else {
+ PixOrCopy v;
+ const int idx =
+ use_color_cache ? VP8LColorCacheContains(&hashers, argb[i]) : -1;
+ if (idx >= 0) {
+ // use_color_cache is true and hashers contains argb[i]
+ // push pixel as a color cache index
+ v = PixOrCopyCreateCacheIdx(idx);
+ } else {
+ if (use_color_cache) VP8LColorCacheInsert(&hashers, argb[i]);
+ v = PixOrCopyCreateLiteral(argb[i]);
+ }
+ VP8LBackwardRefsCursorAdd(refs, v);
+ ++i;
+ }
+ }
+ ok = !refs->error_;
+ Error:
+ if (cc_init) VP8LColorCacheClear(&hashers);
+ return ok;
+}
+
+// Returns 1 on success.
+extern int VP8LBackwardReferencesTraceBackwards(
+ int xsize, int ysize, const uint32_t* const argb, int cache_bits,
+ const VP8LHashChain* const hash_chain,
+ const VP8LBackwardRefs* const refs_src, VP8LBackwardRefs* const refs_dst);
+int VP8LBackwardReferencesTraceBackwards(int xsize, int ysize,
+ const uint32_t* const argb,
+ int cache_bits,
+ const VP8LHashChain* const hash_chain,
+ const VP8LBackwardRefs* const refs_src,
+ VP8LBackwardRefs* const refs_dst) {
+ int ok = 0;
+ const int dist_array_size = xsize * ysize;
+ uint16_t* chosen_path = NULL;
+ int chosen_path_size = 0;
+ uint16_t* dist_array =
+ (uint16_t*)WebPSafeMalloc(dist_array_size, sizeof(*dist_array));
+
+ if (dist_array == NULL) goto Error;
+
+ if (!BackwardReferencesHashChainDistanceOnly(
+ xsize, ysize, argb, cache_bits, hash_chain, refs_src, dist_array)) {
+ goto Error;
+ }
+ TraceBackwards(dist_array, dist_array_size, &chosen_path, &chosen_path_size);
+ if (!BackwardReferencesHashChainFollowChosenPath(
+ argb, cache_bits, chosen_path, chosen_path_size, hash_chain,
+ refs_dst)) {
+ goto Error;
+ }
+ ok = 1;
+ Error:
+ WebPSafeFree(dist_array);
+ return ok;
+}
diff --git a/media/libwebp/src/enc/backward_references_enc.c b/media/libwebp/src/enc/backward_references_enc.c
new file mode 100644
index 0000000000..49a0fac034
--- /dev/null
+++ b/media/libwebp/src/enc/backward_references_enc.c
@@ -0,0 +1,1068 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+//
+
+#include "src/enc/backward_references_enc.h"
+
+#include <assert.h>
+#include <float.h>
+#include <math.h>
+
+#include "src/dsp/dsp.h"
+#include "src/dsp/lossless.h"
+#include "src/dsp/lossless_common.h"
+#include "src/enc/histogram_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/utils/color_cache_utils.h"
+#include "src/utils/utils.h"
+#include "src/webp/encode.h"
+
+#define MIN_BLOCK_SIZE 256 // minimum block size for backward references
+
+#define MAX_ENTROPY (1e30f)
+
+// 1M window (4M bytes) minus 120 special codes for short distances.
+#define WINDOW_SIZE ((1 << WINDOW_SIZE_BITS) - 120)
+
+// Minimum number of pixels for which it is cheaper to encode a
+// distance + length instead of each pixel as a literal.
+#define MIN_LENGTH 4
+
+// -----------------------------------------------------------------------------
+
+static const uint8_t plane_to_code_lut[128] = {
+ 96, 73, 55, 39, 23, 13, 5, 1, 255, 255, 255, 255, 255, 255, 255, 255,
+ 101, 78, 58, 42, 26, 16, 8, 2, 0, 3, 9, 17, 27, 43, 59, 79,
+ 102, 86, 62, 46, 32, 20, 10, 6, 4, 7, 11, 21, 33, 47, 63, 87,
+ 105, 90, 70, 52, 37, 28, 18, 14, 12, 15, 19, 29, 38, 53, 71, 91,
+ 110, 99, 82, 66, 48, 35, 30, 24, 22, 25, 31, 36, 49, 67, 83, 100,
+ 115, 108, 94, 76, 64, 50, 44, 40, 34, 41, 45, 51, 65, 77, 95, 109,
+ 118, 113, 103, 92, 80, 68, 60, 56, 54, 57, 61, 69, 81, 93, 104, 114,
+ 119, 116, 111, 106, 97, 88, 84, 74, 72, 75, 85, 89, 98, 107, 112, 117
+};
+
+extern int VP8LDistanceToPlaneCode(int xsize, int dist);
+int VP8LDistanceToPlaneCode(int xsize, int dist) {
+ const int yoffset = dist / xsize;
+ const int xoffset = dist - yoffset * xsize;
+ if (xoffset <= 8 && yoffset < 8) {
+ return plane_to_code_lut[yoffset * 16 + 8 - xoffset] + 1;
+ } else if (xoffset > xsize - 8 && yoffset < 7) {
+ return plane_to_code_lut[(yoffset + 1) * 16 + 8 + (xsize - xoffset)] + 1;
+ }
+ return dist + 120;
+}
+
+// Returns the exact index where array1 and array2 are different. For an index
+// inferior or equal to best_len_match, the return value just has to be strictly
+// inferior to best_len_match. The current behavior is to return 0 if this index
+// is best_len_match, and the index itself otherwise.
+// If no two elements are the same, it returns max_limit.
+static WEBP_INLINE int FindMatchLength(const uint32_t* const array1,
+ const uint32_t* const array2,
+ int best_len_match, int max_limit) {
+ // Before 'expensive' linear match, check if the two arrays match at the
+ // current best length index.
+ if (array1[best_len_match] != array2[best_len_match]) return 0;
+
+ return VP8LVectorMismatch(array1, array2, max_limit);
+}
+
+// -----------------------------------------------------------------------------
+// VP8LBackwardRefs
+
+struct PixOrCopyBlock {
+ PixOrCopyBlock* next_; // next block (or NULL)
+ PixOrCopy* start_; // data start
+ int size_; // currently used size
+};
+
+extern void VP8LClearBackwardRefs(VP8LBackwardRefs* const refs);
+void VP8LClearBackwardRefs(VP8LBackwardRefs* const refs) {
+ assert(refs != NULL);
+ if (refs->tail_ != NULL) {
+ *refs->tail_ = refs->free_blocks_; // recycle all blocks at once
+ }
+ refs->free_blocks_ = refs->refs_;
+ refs->tail_ = &refs->refs_;
+ refs->last_block_ = NULL;
+ refs->refs_ = NULL;
+}
+
+void VP8LBackwardRefsClear(VP8LBackwardRefs* const refs) {
+ assert(refs != NULL);
+ VP8LClearBackwardRefs(refs);
+ while (refs->free_blocks_ != NULL) {
+ PixOrCopyBlock* const next = refs->free_blocks_->next_;
+ WebPSafeFree(refs->free_blocks_);
+ refs->free_blocks_ = next;
+ }
+}
+
+// Swaps the content of two VP8LBackwardRefs.
+static void BackwardRefsSwap(VP8LBackwardRefs* const refs1,
+ VP8LBackwardRefs* const refs2) {
+ const int point_to_refs1 =
+ (refs1->tail_ != NULL && refs1->tail_ == &refs1->refs_);
+ const int point_to_refs2 =
+ (refs2->tail_ != NULL && refs2->tail_ == &refs2->refs_);
+ const VP8LBackwardRefs tmp = *refs1;
+ *refs1 = *refs2;
+ *refs2 = tmp;
+ if (point_to_refs2) refs1->tail_ = &refs1->refs_;
+ if (point_to_refs1) refs2->tail_ = &refs2->refs_;
+}
+
+void VP8LBackwardRefsInit(VP8LBackwardRefs* const refs, int block_size) {
+ assert(refs != NULL);
+ memset(refs, 0, sizeof(*refs));
+ refs->tail_ = &refs->refs_;
+ refs->block_size_ =
+ (block_size < MIN_BLOCK_SIZE) ? MIN_BLOCK_SIZE : block_size;
+}
+
+VP8LRefsCursor VP8LRefsCursorInit(const VP8LBackwardRefs* const refs) {
+ VP8LRefsCursor c;
+ c.cur_block_ = refs->refs_;
+ if (refs->refs_ != NULL) {
+ c.cur_pos = c.cur_block_->start_;
+ c.last_pos_ = c.cur_pos + c.cur_block_->size_;
+ } else {
+ c.cur_pos = NULL;
+ c.last_pos_ = NULL;
+ }
+ return c;
+}
+
+void VP8LRefsCursorNextBlock(VP8LRefsCursor* const c) {
+ PixOrCopyBlock* const b = c->cur_block_->next_;
+ c->cur_pos = (b == NULL) ? NULL : b->start_;
+ c->last_pos_ = (b == NULL) ? NULL : b->start_ + b->size_;
+ c->cur_block_ = b;
+}
+
+// Create a new block, either from the free list or allocated
+static PixOrCopyBlock* BackwardRefsNewBlock(VP8LBackwardRefs* const refs) {
+ PixOrCopyBlock* b = refs->free_blocks_;
+ if (b == NULL) { // allocate new memory chunk
+ const size_t total_size =
+ sizeof(*b) + refs->block_size_ * sizeof(*b->start_);
+ b = (PixOrCopyBlock*)WebPSafeMalloc(1ULL, total_size);
+ if (b == NULL) {
+ refs->error_ |= 1;
+ return NULL;
+ }
+ b->start_ = (PixOrCopy*)((uint8_t*)b + sizeof(*b)); // not always aligned
+ } else { // recycle from free-list
+ refs->free_blocks_ = b->next_;
+ }
+ *refs->tail_ = b;
+ refs->tail_ = &b->next_;
+ refs->last_block_ = b;
+ b->next_ = NULL;
+ b->size_ = 0;
+ return b;
+}
+
+// Return 1 on success, 0 on error.
+static int BackwardRefsClone(const VP8LBackwardRefs* const from,
+ VP8LBackwardRefs* const to) {
+ const PixOrCopyBlock* block_from = from->refs_;
+ VP8LClearBackwardRefs(to);
+ while (block_from != NULL) {
+ PixOrCopyBlock* const block_to = BackwardRefsNewBlock(to);
+ if (block_to == NULL) return 0;
+ memcpy(block_to->start_, block_from->start_,
+ block_from->size_ * sizeof(PixOrCopy));
+ block_to->size_ = block_from->size_;
+ block_from = block_from->next_;
+ }
+ return 1;
+}
+
+extern void VP8LBackwardRefsCursorAdd(VP8LBackwardRefs* const refs,
+ const PixOrCopy v);
+void VP8LBackwardRefsCursorAdd(VP8LBackwardRefs* const refs,
+ const PixOrCopy v) {
+ PixOrCopyBlock* b = refs->last_block_;
+ if (b == NULL || b->size_ == refs->block_size_) {
+ b = BackwardRefsNewBlock(refs);
+ if (b == NULL) return; // refs->error_ is set
+ }
+ b->start_[b->size_++] = v;
+}
+
+// -----------------------------------------------------------------------------
+// Hash chains
+
+int VP8LHashChainInit(VP8LHashChain* const p, int size) {
+ assert(p->size_ == 0);
+ assert(p->offset_length_ == NULL);
+ assert(size > 0);
+ p->offset_length_ =
+ (uint32_t*)WebPSafeMalloc(size, sizeof(*p->offset_length_));
+ if (p->offset_length_ == NULL) return 0;
+ p->size_ = size;
+
+ return 1;
+}
+
+void VP8LHashChainClear(VP8LHashChain* const p) {
+ assert(p != NULL);
+ WebPSafeFree(p->offset_length_);
+
+ p->size_ = 0;
+ p->offset_length_ = NULL;
+}
+
+// -----------------------------------------------------------------------------
+
+static const uint32_t kHashMultiplierHi = 0xc6a4a793u;
+static const uint32_t kHashMultiplierLo = 0x5bd1e996u;
+
+static WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW WEBP_INLINE
+uint32_t GetPixPairHash64(const uint32_t* const argb) {
+ uint32_t key;
+ key = argb[1] * kHashMultiplierHi;
+ key += argb[0] * kHashMultiplierLo;
+ key = key >> (32 - HASH_BITS);
+ return key;
+}
+
+// Returns the maximum number of hash chain lookups to do for a
+// given compression quality. Return value in range [8, 86].
+static int GetMaxItersForQuality(int quality) {
+ return 8 + (quality * quality) / 128;
+}
+
+static int GetWindowSizeForHashChain(int quality, int xsize) {
+ const int max_window_size = (quality > 75) ? WINDOW_SIZE
+ : (quality > 50) ? (xsize << 8)
+ : (quality > 25) ? (xsize << 6)
+ : (xsize << 4);
+ assert(xsize > 0);
+ return (max_window_size > WINDOW_SIZE) ? WINDOW_SIZE : max_window_size;
+}
+
+static WEBP_INLINE int MaxFindCopyLength(int len) {
+ return (len < MAX_LENGTH) ? len : MAX_LENGTH;
+}
+
+int VP8LHashChainFill(VP8LHashChain* const p, int quality,
+ const uint32_t* const argb, int xsize, int ysize,
+ int low_effort, const WebPPicture* const pic,
+ int percent_range, int* const percent) {
+ const int size = xsize * ysize;
+ const int iter_max = GetMaxItersForQuality(quality);
+ const uint32_t window_size = GetWindowSizeForHashChain(quality, xsize);
+ int remaining_percent = percent_range;
+ int percent_start = *percent;
+ int pos;
+ int argb_comp;
+ uint32_t base_position;
+ int32_t* hash_to_first_index;
+ // Temporarily use the p->offset_length_ as a hash chain.
+ int32_t* chain = (int32_t*)p->offset_length_;
+ assert(size > 0);
+ assert(p->size_ != 0);
+ assert(p->offset_length_ != NULL);
+
+ if (size <= 2) {
+ p->offset_length_[0] = p->offset_length_[size - 1] = 0;
+ return 1;
+ }
+
+ hash_to_first_index =
+ (int32_t*)WebPSafeMalloc(HASH_SIZE, sizeof(*hash_to_first_index));
+ if (hash_to_first_index == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+
+ percent_range = remaining_percent / 2;
+ remaining_percent -= percent_range;
+
+ // Set the int32_t array to -1.
+ memset(hash_to_first_index, 0xff, HASH_SIZE * sizeof(*hash_to_first_index));
+ // Fill the chain linking pixels with the same hash.
+ argb_comp = (argb[0] == argb[1]);
+ for (pos = 0; pos < size - 2;) {
+ uint32_t hash_code;
+ const int argb_comp_next = (argb[pos + 1] == argb[pos + 2]);
+ if (argb_comp && argb_comp_next) {
+ // Consecutive pixels with the same color will share the same hash.
+ // We therefore use a different hash: the color and its repetition
+ // length.
+ uint32_t tmp[2];
+ uint32_t len = 1;
+ tmp[0] = argb[pos];
+ // Figure out how far the pixels are the same.
+ // The last pixel has a different 64 bit hash, as its next pixel does
+ // not have the same color, so we just need to get to the last pixel equal
+ // to its follower.
+ while (pos + (int)len + 2 < size && argb[pos + len + 2] == argb[pos]) {
+ ++len;
+ }
+ if (len > MAX_LENGTH) {
+ // Skip the pixels that match for distance=1 and length>MAX_LENGTH
+ // because they are linked to their predecessor and we automatically
+ // check that in the main for loop below. Skipping means setting no
+ // predecessor in the chain, hence -1.
+ memset(chain + pos, 0xff, (len - MAX_LENGTH) * sizeof(*chain));
+ pos += len - MAX_LENGTH;
+ len = MAX_LENGTH;
+ }
+ // Process the rest of the hash chain.
+ while (len) {
+ tmp[1] = len--;
+ hash_code = GetPixPairHash64(tmp);
+ chain[pos] = hash_to_first_index[hash_code];
+ hash_to_first_index[hash_code] = pos++;
+ }
+ argb_comp = 0;
+ } else {
+ // Just move one pixel forward.
+ hash_code = GetPixPairHash64(argb + pos);
+ chain[pos] = hash_to_first_index[hash_code];
+ hash_to_first_index[hash_code] = pos++;
+ argb_comp = argb_comp_next;
+ }
+
+ if (!WebPReportProgress(
+ pic, percent_start + percent_range * pos / (size - 2), percent)) {
+ WebPSafeFree(hash_to_first_index);
+ return 0;
+ }
+ }
+ // Process the penultimate pixel.
+ chain[pos] = hash_to_first_index[GetPixPairHash64(argb + pos)];
+
+ WebPSafeFree(hash_to_first_index);
+
+ percent_start += percent_range;
+ if (!WebPReportProgress(pic, percent_start, percent)) return 0;
+ percent_range = remaining_percent;
+
+ // Find the best match interval at each pixel, defined by an offset to the
+ // pixel and a length. The right-most pixel cannot match anything to the right
+ // (hence a best length of 0) and the left-most pixel nothing to the left
+ // (hence an offset of 0).
+ assert(size > 2);
+ p->offset_length_[0] = p->offset_length_[size - 1] = 0;
+ for (base_position = size - 2; base_position > 0;) {
+ const int max_len = MaxFindCopyLength(size - 1 - base_position);
+ const uint32_t* const argb_start = argb + base_position;
+ int iter = iter_max;
+ int best_length = 0;
+ uint32_t best_distance = 0;
+ uint32_t best_argb;
+ const int min_pos =
+ (base_position > window_size) ? base_position - window_size : 0;
+ const int length_max = (max_len < 256) ? max_len : 256;
+ uint32_t max_base_position;
+
+ pos = chain[base_position];
+ if (!low_effort) {
+ int curr_length;
+ // Heuristic: use the comparison with the above line as an initialization.
+ if (base_position >= (uint32_t)xsize) {
+ curr_length = FindMatchLength(argb_start - xsize, argb_start,
+ best_length, max_len);
+ if (curr_length > best_length) {
+ best_length = curr_length;
+ best_distance = xsize;
+ }
+ --iter;
+ }
+ // Heuristic: compare to the previous pixel.
+ curr_length =
+ FindMatchLength(argb_start - 1, argb_start, best_length, max_len);
+ if (curr_length > best_length) {
+ best_length = curr_length;
+ best_distance = 1;
+ }
+ --iter;
+ // Skip the for loop if we already have the maximum.
+ if (best_length == MAX_LENGTH) pos = min_pos - 1;
+ }
+ best_argb = argb_start[best_length];
+
+ for (; pos >= min_pos && --iter; pos = chain[pos]) {
+ int curr_length;
+ assert(base_position > (uint32_t)pos);
+
+ if (argb[pos + best_length] != best_argb) continue;
+
+ curr_length = VP8LVectorMismatch(argb + pos, argb_start, max_len);
+ if (best_length < curr_length) {
+ best_length = curr_length;
+ best_distance = base_position - pos;
+ best_argb = argb_start[best_length];
+ // Stop if we have reached a good enough length.
+ if (best_length >= length_max) break;
+ }
+ }
+ // We have the best match but in case the two intervals continue matching
+ // to the left, we have the best matches for the left-extended pixels.
+ max_base_position = base_position;
+ while (1) {
+ assert(best_length <= MAX_LENGTH);
+ assert(best_distance <= WINDOW_SIZE);
+ p->offset_length_[base_position] =
+ (best_distance << MAX_LENGTH_BITS) | (uint32_t)best_length;
+ --base_position;
+ // Stop if we don't have a match or if we are out of bounds.
+ if (best_distance == 0 || base_position == 0) break;
+ // Stop if we cannot extend the matching intervals to the left.
+ if (base_position < best_distance ||
+ argb[base_position - best_distance] != argb[base_position]) {
+ break;
+ }
+ // Stop if we are matching at its limit because there could be a closer
+ // matching interval with the same maximum length. Then again, if the
+ // matching interval is as close as possible (best_distance == 1), we will
+ // never find anything better so let's continue.
+ if (best_length == MAX_LENGTH && best_distance != 1 &&
+ base_position + MAX_LENGTH < max_base_position) {
+ break;
+ }
+ if (best_length < MAX_LENGTH) {
+ ++best_length;
+ max_base_position = base_position;
+ }
+ }
+
+ if (!WebPReportProgress(pic,
+ percent_start + percent_range *
+ (size - 2 - base_position) /
+ (size - 2),
+ percent)) {
+ return 0;
+ }
+ }
+
+ return WebPReportProgress(pic, percent_start + percent_range, percent);
+}
+
+static WEBP_INLINE void AddSingleLiteral(uint32_t pixel, int use_color_cache,
+ VP8LColorCache* const hashers,
+ VP8LBackwardRefs* const refs) {
+ PixOrCopy v;
+ if (use_color_cache) {
+ const uint32_t key = VP8LColorCacheGetIndex(hashers, pixel);
+ if (VP8LColorCacheLookup(hashers, key) == pixel) {
+ v = PixOrCopyCreateCacheIdx(key);
+ } else {
+ v = PixOrCopyCreateLiteral(pixel);
+ VP8LColorCacheSet(hashers, key, pixel);
+ }
+ } else {
+ v = PixOrCopyCreateLiteral(pixel);
+ }
+ VP8LBackwardRefsCursorAdd(refs, v);
+}
+
+static int BackwardReferencesRle(int xsize, int ysize,
+ const uint32_t* const argb,
+ int cache_bits, VP8LBackwardRefs* const refs) {
+ const int pix_count = xsize * ysize;
+ int i, k;
+ const int use_color_cache = (cache_bits > 0);
+ VP8LColorCache hashers;
+
+ if (use_color_cache && !VP8LColorCacheInit(&hashers, cache_bits)) {
+ return 0;
+ }
+ VP8LClearBackwardRefs(refs);
+ // Add first pixel as literal.
+ AddSingleLiteral(argb[0], use_color_cache, &hashers, refs);
+ i = 1;
+ while (i < pix_count) {
+ const int max_len = MaxFindCopyLength(pix_count - i);
+ const int rle_len = FindMatchLength(argb + i, argb + i - 1, 0, max_len);
+ const int prev_row_len = (i < xsize) ? 0 :
+ FindMatchLength(argb + i, argb + i - xsize, 0, max_len);
+ if (rle_len >= prev_row_len && rle_len >= MIN_LENGTH) {
+ VP8LBackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(1, rle_len));
+ // We don't need to update the color cache here since it is always the
+ // same pixel being copied, and that does not change the color cache
+ // state.
+ i += rle_len;
+ } else if (prev_row_len >= MIN_LENGTH) {
+ VP8LBackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(xsize, prev_row_len));
+ if (use_color_cache) {
+ for (k = 0; k < prev_row_len; ++k) {
+ VP8LColorCacheInsert(&hashers, argb[i + k]);
+ }
+ }
+ i += prev_row_len;
+ } else {
+ AddSingleLiteral(argb[i], use_color_cache, &hashers, refs);
+ i++;
+ }
+ }
+ if (use_color_cache) VP8LColorCacheClear(&hashers);
+ return !refs->error_;
+}
+
+static int BackwardReferencesLz77(int xsize, int ysize,
+ const uint32_t* const argb, int cache_bits,
+ const VP8LHashChain* const hash_chain,
+ VP8LBackwardRefs* const refs) {
+ int i;
+ int i_last_check = -1;
+ int ok = 0;
+ int cc_init = 0;
+ const int use_color_cache = (cache_bits > 0);
+ const int pix_count = xsize * ysize;
+ VP8LColorCache hashers;
+
+ if (use_color_cache) {
+ cc_init = VP8LColorCacheInit(&hashers, cache_bits);
+ if (!cc_init) goto Error;
+ }
+ VP8LClearBackwardRefs(refs);
+ for (i = 0; i < pix_count;) {
+ // Alternative#1: Code the pixels starting at 'i' using backward reference.
+ int offset = 0;
+ int len = 0;
+ int j;
+ VP8LHashChainFindCopy(hash_chain, i, &offset, &len);
+ if (len >= MIN_LENGTH) {
+ const int len_ini = len;
+ int max_reach = 0;
+ const int j_max =
+ (i + len_ini >= pix_count) ? pix_count - 1 : i + len_ini;
+ // Only start from what we have not checked already.
+ i_last_check = (i > i_last_check) ? i : i_last_check;
+ // We know the best match for the current pixel but we try to find the
+ // best matches for the current pixel AND the next one combined.
+ // The naive method would use the intervals:
+ // [i,i+len) + [i+len, length of best match at i+len)
+ // while we check if we can use:
+ // [i,j) (where j<=i+len) + [j, length of best match at j)
+ for (j = i_last_check + 1; j <= j_max; ++j) {
+ const int len_j = VP8LHashChainFindLength(hash_chain, j);
+ const int reach =
+ j + (len_j >= MIN_LENGTH ? len_j : 1); // 1 for single literal.
+ if (reach > max_reach) {
+ len = j - i;
+ max_reach = reach;
+ if (max_reach >= pix_count) break;
+ }
+ }
+ } else {
+ len = 1;
+ }
+ // Go with literal or backward reference.
+ assert(len > 0);
+ if (len == 1) {
+ AddSingleLiteral(argb[i], use_color_cache, &hashers, refs);
+ } else {
+ VP8LBackwardRefsCursorAdd(refs, PixOrCopyCreateCopy(offset, len));
+ if (use_color_cache) {
+ for (j = i; j < i + len; ++j) VP8LColorCacheInsert(&hashers, argb[j]);
+ }
+ }
+ i += len;
+ }
+
+ ok = !refs->error_;
+ Error:
+ if (cc_init) VP8LColorCacheClear(&hashers);
+ return ok;
+}
+
+// Compute an LZ77 by forcing matches to happen within a given distance cost.
+// We therefore limit the algorithm to the lowest 32 values in the PlaneCode
+// definition.
+#define WINDOW_OFFSETS_SIZE_MAX 32
+static int BackwardReferencesLz77Box(int xsize, int ysize,
+ const uint32_t* const argb, int cache_bits,
+ const VP8LHashChain* const hash_chain_best,
+ VP8LHashChain* hash_chain,
+ VP8LBackwardRefs* const refs) {
+ int i;
+ const int pix_count = xsize * ysize;
+ uint16_t* counts;
+ int window_offsets[WINDOW_OFFSETS_SIZE_MAX] = {0};
+ int window_offsets_new[WINDOW_OFFSETS_SIZE_MAX] = {0};
+ int window_offsets_size = 0;
+ int window_offsets_new_size = 0;
+ uint16_t* const counts_ini =
+ (uint16_t*)WebPSafeMalloc(xsize * ysize, sizeof(*counts_ini));
+ int best_offset_prev = -1, best_length_prev = -1;
+ if (counts_ini == NULL) return 0;
+
+ // counts[i] counts how many times a pixel is repeated starting at position i.
+ i = pix_count - 2;
+ counts = counts_ini + i;
+ counts[1] = 1;
+ for (; i >= 0; --i, --counts) {
+ if (argb[i] == argb[i + 1]) {
+ // Max out the counts to MAX_LENGTH.
+ counts[0] = counts[1] + (counts[1] != MAX_LENGTH);
+ } else {
+ counts[0] = 1;
+ }
+ }
+
+ // Figure out the window offsets around a pixel. They are stored in a
+ // spiraling order around the pixel as defined by VP8LDistanceToPlaneCode.
+ {
+ int x, y;
+ for (y = 0; y <= 6; ++y) {
+ for (x = -6; x <= 6; ++x) {
+ const int offset = y * xsize + x;
+ int plane_code;
+ // Ignore offsets that bring us after the pixel.
+ if (offset <= 0) continue;
+ plane_code = VP8LDistanceToPlaneCode(xsize, offset) - 1;
+ if (plane_code >= WINDOW_OFFSETS_SIZE_MAX) continue;
+ window_offsets[plane_code] = offset;
+ }
+ }
+ // For narrow images, not all plane codes are reached, so remove those.
+ for (i = 0; i < WINDOW_OFFSETS_SIZE_MAX; ++i) {
+ if (window_offsets[i] == 0) continue;
+ window_offsets[window_offsets_size++] = window_offsets[i];
+ }
+ // Given a pixel P, find the offsets that reach pixels unreachable from P-1
+ // with any of the offsets in window_offsets[].
+ for (i = 0; i < window_offsets_size; ++i) {
+ int j;
+ int is_reachable = 0;
+ for (j = 0; j < window_offsets_size && !is_reachable; ++j) {
+ is_reachable |= (window_offsets[i] == window_offsets[j] + 1);
+ }
+ if (!is_reachable) {
+ window_offsets_new[window_offsets_new_size] = window_offsets[i];
+ ++window_offsets_new_size;
+ }
+ }
+ }
+
+ hash_chain->offset_length_[0] = 0;
+ for (i = 1; i < pix_count; ++i) {
+ int ind;
+ int best_length = VP8LHashChainFindLength(hash_chain_best, i);
+ int best_offset;
+ int do_compute = 1;
+
+ if (best_length >= MAX_LENGTH) {
+ // Do not recompute the best match if we already have a maximal one in the
+ // window.
+ best_offset = VP8LHashChainFindOffset(hash_chain_best, i);
+ for (ind = 0; ind < window_offsets_size; ++ind) {
+ if (best_offset == window_offsets[ind]) {
+ do_compute = 0;
+ break;
+ }
+ }
+ }
+ if (do_compute) {
+ // Figure out if we should use the offset/length from the previous pixel
+ // as an initial guess and therefore only inspect the offsets in
+ // window_offsets_new[].
+ const int use_prev =
+ (best_length_prev > 1) && (best_length_prev < MAX_LENGTH);
+ const int num_ind =
+ use_prev ? window_offsets_new_size : window_offsets_size;
+ best_length = use_prev ? best_length_prev - 1 : 0;
+ best_offset = use_prev ? best_offset_prev : 0;
+ // Find the longest match in a window around the pixel.
+ for (ind = 0; ind < num_ind; ++ind) {
+ int curr_length = 0;
+ int j = i;
+ int j_offset =
+ use_prev ? i - window_offsets_new[ind] : i - window_offsets[ind];
+ if (j_offset < 0 || argb[j_offset] != argb[i]) continue;
+ // The longest match is the sum of how many times each pixel is
+ // repeated.
+ do {
+ const int counts_j_offset = counts_ini[j_offset];
+ const int counts_j = counts_ini[j];
+ if (counts_j_offset != counts_j) {
+ curr_length +=
+ (counts_j_offset < counts_j) ? counts_j_offset : counts_j;
+ break;
+ }
+ // The same color is repeated counts_pos times at j_offset and j.
+ curr_length += counts_j_offset;
+ j_offset += counts_j_offset;
+ j += counts_j_offset;
+ } while (curr_length <= MAX_LENGTH && j < pix_count &&
+ argb[j_offset] == argb[j]);
+ if (best_length < curr_length) {
+ best_offset =
+ use_prev ? window_offsets_new[ind] : window_offsets[ind];
+ if (curr_length >= MAX_LENGTH) {
+ best_length = MAX_LENGTH;
+ break;
+ } else {
+ best_length = curr_length;
+ }
+ }
+ }
+ }
+
+ assert(i + best_length <= pix_count);
+ assert(best_length <= MAX_LENGTH);
+ if (best_length <= MIN_LENGTH) {
+ hash_chain->offset_length_[i] = 0;
+ best_offset_prev = 0;
+ best_length_prev = 0;
+ } else {
+ hash_chain->offset_length_[i] =
+ (best_offset << MAX_LENGTH_BITS) | (uint32_t)best_length;
+ best_offset_prev = best_offset;
+ best_length_prev = best_length;
+ }
+ }
+ hash_chain->offset_length_[0] = 0;
+ WebPSafeFree(counts_ini);
+
+ return BackwardReferencesLz77(xsize, ysize, argb, cache_bits, hash_chain,
+ refs);
+}
+
+// -----------------------------------------------------------------------------
+
+static void BackwardReferences2DLocality(int xsize,
+ const VP8LBackwardRefs* const refs) {
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ while (VP8LRefsCursorOk(&c)) {
+ if (PixOrCopyIsCopy(c.cur_pos)) {
+ const int dist = c.cur_pos->argb_or_distance;
+ const int transformed_dist = VP8LDistanceToPlaneCode(xsize, dist);
+ c.cur_pos->argb_or_distance = transformed_dist;
+ }
+ VP8LRefsCursorNext(&c);
+ }
+}
+
+// Evaluate optimal cache bits for the local color cache.
+// The input *best_cache_bits sets the maximum cache bits to use (passing 0
+// implies disabling the local color cache). The local color cache is also
+// disabled for the lower (<= 25) quality.
+// Returns 0 in case of memory error.
+static int CalculateBestCacheSize(const uint32_t* argb, int quality,
+ const VP8LBackwardRefs* const refs,
+ int* const best_cache_bits) {
+ int i;
+ const int cache_bits_max = (quality <= 25) ? 0 : *best_cache_bits;
+ float entropy_min = MAX_ENTROPY;
+ int cc_init[MAX_COLOR_CACHE_BITS + 1] = { 0 };
+ VP8LColorCache hashers[MAX_COLOR_CACHE_BITS + 1];
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ VP8LHistogram* histos[MAX_COLOR_CACHE_BITS + 1] = { NULL };
+ int ok = 0;
+
+ assert(cache_bits_max >= 0 && cache_bits_max <= MAX_COLOR_CACHE_BITS);
+
+ if (cache_bits_max == 0) {
+ *best_cache_bits = 0;
+ // Local color cache is disabled.
+ return 1;
+ }
+
+ // Allocate data.
+ for (i = 0; i <= cache_bits_max; ++i) {
+ histos[i] = VP8LAllocateHistogram(i);
+ if (histos[i] == NULL) goto Error;
+ VP8LHistogramInit(histos[i], i, /*init_arrays=*/ 1);
+ if (i == 0) continue;
+ cc_init[i] = VP8LColorCacheInit(&hashers[i], i);
+ if (!cc_init[i]) goto Error;
+ }
+
+ // Find the cache_bits giving the lowest entropy. The search is done in a
+ // brute-force way as the function (entropy w.r.t cache_bits) can be
+ // anything in practice.
+ while (VP8LRefsCursorOk(&c)) {
+ const PixOrCopy* const v = c.cur_pos;
+ if (PixOrCopyIsLiteral(v)) {
+ const uint32_t pix = *argb++;
+ const uint32_t a = (pix >> 24) & 0xff;
+ const uint32_t r = (pix >> 16) & 0xff;
+ const uint32_t g = (pix >> 8) & 0xff;
+ const uint32_t b = (pix >> 0) & 0xff;
+ // The keys of the caches can be derived from the longest one.
+ int key = VP8LHashPix(pix, 32 - cache_bits_max);
+ // Do not use the color cache for cache_bits = 0.
+ ++histos[0]->blue_[b];
+ ++histos[0]->literal_[g];
+ ++histos[0]->red_[r];
+ ++histos[0]->alpha_[a];
+ // Deal with cache_bits > 0.
+ for (i = cache_bits_max; i >= 1; --i, key >>= 1) {
+ if (VP8LColorCacheLookup(&hashers[i], key) == pix) {
+ ++histos[i]->literal_[NUM_LITERAL_CODES + NUM_LENGTH_CODES + key];
+ } else {
+ VP8LColorCacheSet(&hashers[i], key, pix);
+ ++histos[i]->blue_[b];
+ ++histos[i]->literal_[g];
+ ++histos[i]->red_[r];
+ ++histos[i]->alpha_[a];
+ }
+ }
+ } else {
+ int code, extra_bits, extra_bits_value;
+ // We should compute the contribution of the (distance,length)
+ // histograms but those are the same independently from the cache size.
+ // As those constant contributions are in the end added to the other
+ // histogram contributions, we can ignore them, except for the length
+ // prefix that is part of the literal_ histogram.
+ int len = PixOrCopyLength(v);
+ uint32_t argb_prev = *argb ^ 0xffffffffu;
+ VP8LPrefixEncode(len, &code, &extra_bits, &extra_bits_value);
+ for (i = 0; i <= cache_bits_max; ++i) {
+ ++histos[i]->literal_[NUM_LITERAL_CODES + code];
+ }
+ // Update the color caches.
+ do {
+ if (*argb != argb_prev) {
+ // Efficiency: insert only if the color changes.
+ int key = VP8LHashPix(*argb, 32 - cache_bits_max);
+ for (i = cache_bits_max; i >= 1; --i, key >>= 1) {
+ hashers[i].colors_[key] = *argb;
+ }
+ argb_prev = *argb;
+ }
+ argb++;
+ } while (--len != 0);
+ }
+ VP8LRefsCursorNext(&c);
+ }
+
+ for (i = 0; i <= cache_bits_max; ++i) {
+ const float entropy = VP8LHistogramEstimateBits(histos[i]);
+ if (i == 0 || entropy < entropy_min) {
+ entropy_min = entropy;
+ *best_cache_bits = i;
+ }
+ }
+ ok = 1;
+ Error:
+ for (i = 0; i <= cache_bits_max; ++i) {
+ if (cc_init[i]) VP8LColorCacheClear(&hashers[i]);
+ VP8LFreeHistogram(histos[i]);
+ }
+ return ok;
+}
+
+// Update (in-place) backward references for specified cache_bits.
+static int BackwardRefsWithLocalCache(const uint32_t* const argb,
+ int cache_bits,
+ VP8LBackwardRefs* const refs) {
+ int pixel_index = 0;
+ VP8LColorCache hashers;
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ if (!VP8LColorCacheInit(&hashers, cache_bits)) return 0;
+
+ while (VP8LRefsCursorOk(&c)) {
+ PixOrCopy* const v = c.cur_pos;
+ if (PixOrCopyIsLiteral(v)) {
+ const uint32_t argb_literal = v->argb_or_distance;
+ const int ix = VP8LColorCacheContains(&hashers, argb_literal);
+ if (ix >= 0) {
+ // hashers contains argb_literal
+ *v = PixOrCopyCreateCacheIdx(ix);
+ } else {
+ VP8LColorCacheInsert(&hashers, argb_literal);
+ }
+ ++pixel_index;
+ } else {
+ // refs was created without local cache, so it can not have cache indexes.
+ int k;
+ assert(PixOrCopyIsCopy(v));
+ for (k = 0; k < v->len; ++k) {
+ VP8LColorCacheInsert(&hashers, argb[pixel_index++]);
+ }
+ }
+ VP8LRefsCursorNext(&c);
+ }
+ VP8LColorCacheClear(&hashers);
+ return 1;
+}
+
+static VP8LBackwardRefs* GetBackwardReferencesLowEffort(
+ int width, int height, const uint32_t* const argb,
+ int* const cache_bits, const VP8LHashChain* const hash_chain,
+ VP8LBackwardRefs* const refs_lz77) {
+ *cache_bits = 0;
+ if (!BackwardReferencesLz77(width, height, argb, 0, hash_chain, refs_lz77)) {
+ return NULL;
+ }
+ BackwardReferences2DLocality(width, refs_lz77);
+ return refs_lz77;
+}
+
+extern int VP8LBackwardReferencesTraceBackwards(
+ int xsize, int ysize, const uint32_t* const argb, int cache_bits,
+ const VP8LHashChain* const hash_chain,
+ const VP8LBackwardRefs* const refs_src, VP8LBackwardRefs* const refs_dst);
+static int GetBackwardReferences(int width, int height,
+ const uint32_t* const argb, int quality,
+ int lz77_types_to_try, int cache_bits_max,
+ int do_no_cache,
+ const VP8LHashChain* const hash_chain,
+ VP8LBackwardRefs* const refs,
+ int* const cache_bits_best) {
+ VP8LHistogram* histo = NULL;
+ int i, lz77_type;
+ // Index 0 is for a color cache, index 1 for no cache (if needed).
+ int lz77_types_best[2] = {0, 0};
+ float bit_costs_best[2] = {FLT_MAX, FLT_MAX};
+ VP8LHashChain hash_chain_box;
+ VP8LBackwardRefs* const refs_tmp = &refs[do_no_cache ? 2 : 1];
+ int status = 0;
+ memset(&hash_chain_box, 0, sizeof(hash_chain_box));
+
+ histo = VP8LAllocateHistogram(MAX_COLOR_CACHE_BITS);
+ if (histo == NULL) goto Error;
+
+ for (lz77_type = 1; lz77_types_to_try;
+ lz77_types_to_try &= ~lz77_type, lz77_type <<= 1) {
+ int res = 0;
+ float bit_cost = 0.f;
+ if ((lz77_types_to_try & lz77_type) == 0) continue;
+ switch (lz77_type) {
+ case kLZ77RLE:
+ res = BackwardReferencesRle(width, height, argb, 0, refs_tmp);
+ break;
+ case kLZ77Standard:
+ // Compute LZ77 with no cache (0 bits), as the ideal LZ77 with a color
+ // cache is not that different in practice.
+ res = BackwardReferencesLz77(width, height, argb, 0, hash_chain,
+ refs_tmp);
+ break;
+ case kLZ77Box:
+ if (!VP8LHashChainInit(&hash_chain_box, width * height)) goto Error;
+ res = BackwardReferencesLz77Box(width, height, argb, 0, hash_chain,
+ &hash_chain_box, refs_tmp);
+ break;
+ default:
+ assert(0);
+ }
+ if (!res) goto Error;
+
+ // Start with the no color cache case.
+ for (i = 1; i >= 0; --i) {
+ int cache_bits = (i == 1) ? 0 : cache_bits_max;
+
+ if (i == 1 && !do_no_cache) continue;
+
+ if (i == 0) {
+ // Try with a color cache.
+ if (!CalculateBestCacheSize(argb, quality, refs_tmp, &cache_bits)) {
+ goto Error;
+ }
+ if (cache_bits > 0) {
+ if (!BackwardRefsWithLocalCache(argb, cache_bits, refs_tmp)) {
+ goto Error;
+ }
+ }
+ }
+
+ if (i == 0 && do_no_cache && cache_bits == 0) {
+ // No need to re-compute bit_cost as it was computed at i == 1.
+ } else {
+ VP8LHistogramCreate(histo, refs_tmp, cache_bits);
+ bit_cost = VP8LHistogramEstimateBits(histo);
+ }
+
+ if (bit_cost < bit_costs_best[i]) {
+ if (i == 1) {
+ // Do not swap as the full cache analysis would have the wrong
+ // VP8LBackwardRefs to start with.
+ if (!BackwardRefsClone(refs_tmp, &refs[1])) goto Error;
+ } else {
+ BackwardRefsSwap(refs_tmp, &refs[0]);
+ }
+ bit_costs_best[i] = bit_cost;
+ lz77_types_best[i] = lz77_type;
+ if (i == 0) *cache_bits_best = cache_bits;
+ }
+ }
+ }
+ assert(lz77_types_best[0] > 0);
+ assert(!do_no_cache || lz77_types_best[1] > 0);
+
+ // Improve on simple LZ77 but only for high quality (TraceBackwards is
+ // costly).
+ for (i = 1; i >= 0; --i) {
+ if (i == 1 && !do_no_cache) continue;
+ if ((lz77_types_best[i] == kLZ77Standard ||
+ lz77_types_best[i] == kLZ77Box) &&
+ quality >= 25) {
+ const VP8LHashChain* const hash_chain_tmp =
+ (lz77_types_best[i] == kLZ77Standard) ? hash_chain : &hash_chain_box;
+ const int cache_bits = (i == 1) ? 0 : *cache_bits_best;
+ float bit_cost_trace;
+ if (!VP8LBackwardReferencesTraceBackwards(width, height, argb, cache_bits,
+ hash_chain_tmp, &refs[i],
+ refs_tmp)) {
+ goto Error;
+ }
+ VP8LHistogramCreate(histo, refs_tmp, cache_bits);
+ bit_cost_trace = VP8LHistogramEstimateBits(histo);
+ if (bit_cost_trace < bit_costs_best[i]) {
+ BackwardRefsSwap(refs_tmp, &refs[i]);
+ }
+ }
+
+ BackwardReferences2DLocality(width, &refs[i]);
+
+ if (i == 1 && lz77_types_best[0] == lz77_types_best[1] &&
+ *cache_bits_best == 0) {
+ // If the best cache size is 0 and we have the same best LZ77, just copy
+ // the data over and stop here.
+ if (!BackwardRefsClone(&refs[1], &refs[0])) goto Error;
+ break;
+ }
+ }
+ status = 1;
+
+ Error:
+ VP8LHashChainClear(&hash_chain_box);
+ VP8LFreeHistogram(histo);
+ return status;
+}
+
+int VP8LGetBackwardReferences(
+ int width, int height, const uint32_t* const argb, int quality,
+ int low_effort, int lz77_types_to_try, int cache_bits_max, int do_no_cache,
+ const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs,
+ int* const cache_bits_best, const WebPPicture* const pic, int percent_range,
+ int* const percent) {
+ if (low_effort) {
+ VP8LBackwardRefs* refs_best;
+ *cache_bits_best = cache_bits_max;
+ refs_best = GetBackwardReferencesLowEffort(
+ width, height, argb, cache_bits_best, hash_chain, refs);
+ if (refs_best == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ // Set it in first position.
+ BackwardRefsSwap(refs_best, &refs[0]);
+ } else {
+ if (!GetBackwardReferences(width, height, argb, quality, lz77_types_to_try,
+ cache_bits_max, do_no_cache, hash_chain, refs,
+ cache_bits_best)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ }
+
+ return WebPReportProgress(pic, *percent + percent_range, percent);
+}
diff --git a/media/libwebp/src/enc/backward_references_enc.h b/media/libwebp/src/enc/backward_references_enc.h
new file mode 100644
index 0000000000..4dff1c27b5
--- /dev/null
+++ b/media/libwebp/src/enc/backward_references_enc.h
@@ -0,0 +1,244 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+//
+
+#ifndef WEBP_ENC_BACKWARD_REFERENCES_ENC_H_
+#define WEBP_ENC_BACKWARD_REFERENCES_ENC_H_
+
+#include <assert.h>
+#include <stdlib.h>
+#include "src/webp/types.h"
+#include "src/webp/encode.h"
+#include "src/webp/format_constants.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// The maximum allowed limit is 11.
+#define MAX_COLOR_CACHE_BITS 10
+
+// -----------------------------------------------------------------------------
+// PixOrCopy
+
+enum Mode {
+ kLiteral,
+ kCacheIdx,
+ kCopy,
+ kNone
+};
+
+typedef struct {
+ // mode as uint8_t to make the memory layout to be exactly 8 bytes.
+ uint8_t mode;
+ uint16_t len;
+ uint32_t argb_or_distance;
+} PixOrCopy;
+
+static WEBP_INLINE PixOrCopy PixOrCopyCreateCopy(uint32_t distance,
+ uint16_t len) {
+ PixOrCopy retval;
+ retval.mode = kCopy;
+ retval.argb_or_distance = distance;
+ retval.len = len;
+ return retval;
+}
+
+static WEBP_INLINE PixOrCopy PixOrCopyCreateCacheIdx(int idx) {
+ PixOrCopy retval;
+ assert(idx >= 0);
+ assert(idx < (1 << MAX_COLOR_CACHE_BITS));
+ retval.mode = kCacheIdx;
+ retval.argb_or_distance = idx;
+ retval.len = 1;
+ return retval;
+}
+
+static WEBP_INLINE PixOrCopy PixOrCopyCreateLiteral(uint32_t argb) {
+ PixOrCopy retval;
+ retval.mode = kLiteral;
+ retval.argb_or_distance = argb;
+ retval.len = 1;
+ return retval;
+}
+
+static WEBP_INLINE int PixOrCopyIsLiteral(const PixOrCopy* const p) {
+ return (p->mode == kLiteral);
+}
+
+static WEBP_INLINE int PixOrCopyIsCacheIdx(const PixOrCopy* const p) {
+ return (p->mode == kCacheIdx);
+}
+
+static WEBP_INLINE int PixOrCopyIsCopy(const PixOrCopy* const p) {
+ return (p->mode == kCopy);
+}
+
+static WEBP_INLINE uint32_t PixOrCopyLiteral(const PixOrCopy* const p,
+ int component) {
+ assert(p->mode == kLiteral);
+ return (p->argb_or_distance >> (component * 8)) & 0xff;
+}
+
+static WEBP_INLINE uint32_t PixOrCopyLength(const PixOrCopy* const p) {
+ return p->len;
+}
+
+static WEBP_INLINE uint32_t PixOrCopyCacheIdx(const PixOrCopy* const p) {
+ assert(p->mode == kCacheIdx);
+ assert(p->argb_or_distance < (1U << MAX_COLOR_CACHE_BITS));
+ return p->argb_or_distance;
+}
+
+static WEBP_INLINE uint32_t PixOrCopyDistance(const PixOrCopy* const p) {
+ assert(p->mode == kCopy);
+ return p->argb_or_distance;
+}
+
+// -----------------------------------------------------------------------------
+// VP8LHashChain
+
+#define HASH_BITS 18
+#define HASH_SIZE (1 << HASH_BITS)
+
+// If you change this, you need MAX_LENGTH_BITS + WINDOW_SIZE_BITS <= 32 as it
+// is used in VP8LHashChain.
+#define MAX_LENGTH_BITS 12
+#define WINDOW_SIZE_BITS 20
+// We want the max value to be attainable and stored in MAX_LENGTH_BITS bits.
+#define MAX_LENGTH ((1 << MAX_LENGTH_BITS) - 1)
+#if MAX_LENGTH_BITS + WINDOW_SIZE_BITS > 32
+#error "MAX_LENGTH_BITS + WINDOW_SIZE_BITS > 32"
+#endif
+
+typedef struct VP8LHashChain VP8LHashChain;
+struct VP8LHashChain {
+ // The 20 most significant bits contain the offset at which the best match
+ // is found. These 20 bits are the limit defined by GetWindowSizeForHashChain
+ // (through WINDOW_SIZE = 1<<20).
+ // The lower 12 bits contain the length of the match. The 12 bit limit is
+ // defined in MaxFindCopyLength with MAX_LENGTH=4096.
+ uint32_t* offset_length_;
+ // This is the maximum size of the hash_chain that can be constructed.
+ // Typically this is the pixel count (width x height) for a given image.
+ int size_;
+};
+
+// Must be called first, to set size.
+int VP8LHashChainInit(VP8LHashChain* const p, int size);
+// Pre-compute the best matches for argb. pic and percent are for progress.
+int VP8LHashChainFill(VP8LHashChain* const p, int quality,
+ const uint32_t* const argb, int xsize, int ysize,
+ int low_effort, const WebPPicture* const pic,
+ int percent_range, int* const percent);
+void VP8LHashChainClear(VP8LHashChain* const p); // release memory
+
+static WEBP_INLINE int VP8LHashChainFindOffset(const VP8LHashChain* const p,
+ const int base_position) {
+ return p->offset_length_[base_position] >> MAX_LENGTH_BITS;
+}
+
+static WEBP_INLINE int VP8LHashChainFindLength(const VP8LHashChain* const p,
+ const int base_position) {
+ return p->offset_length_[base_position] & ((1U << MAX_LENGTH_BITS) - 1);
+}
+
+static WEBP_INLINE void VP8LHashChainFindCopy(const VP8LHashChain* const p,
+ int base_position,
+ int* const offset_ptr,
+ int* const length_ptr) {
+ *offset_ptr = VP8LHashChainFindOffset(p, base_position);
+ *length_ptr = VP8LHashChainFindLength(p, base_position);
+}
+
+// -----------------------------------------------------------------------------
+// VP8LBackwardRefs (block-based backward-references storage)
+
+// maximum number of reference blocks the image will be segmented into
+#define MAX_REFS_BLOCK_PER_IMAGE 16
+
+typedef struct PixOrCopyBlock PixOrCopyBlock; // forward declaration
+typedef struct VP8LBackwardRefs VP8LBackwardRefs;
+
+// Container for blocks chain
+struct VP8LBackwardRefs {
+ int block_size_; // common block-size
+ int error_; // set to true if some memory error occurred
+ PixOrCopyBlock* refs_; // list of currently used blocks
+ PixOrCopyBlock** tail_; // for list recycling
+ PixOrCopyBlock* free_blocks_; // free-list
+ PixOrCopyBlock* last_block_; // used for adding new refs (internal)
+};
+
+// Initialize the object. 'block_size' is the common block size to store
+// references (typically, width * height / MAX_REFS_BLOCK_PER_IMAGE).
+void VP8LBackwardRefsInit(VP8LBackwardRefs* const refs, int block_size);
+// Release memory for backward references.
+void VP8LBackwardRefsClear(VP8LBackwardRefs* const refs);
+
+// Cursor for iterating on references content
+typedef struct {
+ // public:
+ PixOrCopy* cur_pos; // current position
+ // private:
+ PixOrCopyBlock* cur_block_; // current block in the refs list
+ const PixOrCopy* last_pos_; // sentinel for switching to next block
+} VP8LRefsCursor;
+
+// Returns a cursor positioned at the beginning of the references list.
+VP8LRefsCursor VP8LRefsCursorInit(const VP8LBackwardRefs* const refs);
+// Returns true if cursor is pointing at a valid position.
+static WEBP_INLINE int VP8LRefsCursorOk(const VP8LRefsCursor* const c) {
+ return (c->cur_pos != NULL);
+}
+// Move to next block of references. Internal, not to be called directly.
+void VP8LRefsCursorNextBlock(VP8LRefsCursor* const c);
+// Move to next position, or NULL. Should not be called if !VP8LRefsCursorOk().
+static WEBP_INLINE void VP8LRefsCursorNext(VP8LRefsCursor* const c) {
+ assert(c != NULL);
+ assert(VP8LRefsCursorOk(c));
+ if (++c->cur_pos == c->last_pos_) VP8LRefsCursorNextBlock(c);
+}
+
+// -----------------------------------------------------------------------------
+// Main entry points
+
+enum VP8LLZ77Type {
+ kLZ77Standard = 1,
+ kLZ77RLE = 2,
+ kLZ77Box = 4
+};
+
+// Evaluates best possible backward references for specified quality.
+// The input cache_bits to 'VP8LGetBackwardReferences' sets the maximum cache
+// bits to use (passing 0 implies disabling the local color cache).
+// The optimal cache bits is evaluated and set for the *cache_bits_best
+// parameter with the matching refs_best.
+// If do_no_cache == 0, refs is an array of 2 values and the best
+// VP8LBackwardRefs is put in the first element.
+// If do_no_cache != 0, refs is an array of 3 values and the best
+// VP8LBackwardRefs is put in the first element, the best value with no-cache in
+// the second element.
+// In both cases, the last element is used as temporary internally.
+// pic and percent are for progress.
+// Returns false in case of error (stored in pic->error_code).
+int VP8LGetBackwardReferences(
+ int width, int height, const uint32_t* const argb, int quality,
+ int low_effort, int lz77_types_to_try, int cache_bits_max, int do_no_cache,
+ const VP8LHashChain* const hash_chain, VP8LBackwardRefs* const refs,
+ int* const cache_bits_best, const WebPPicture* const pic, int percent_range,
+ int* const percent);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // WEBP_ENC_BACKWARD_REFERENCES_ENC_H_
diff --git a/media/libwebp/src/enc/config_enc.c b/media/libwebp/src/enc/config_enc.c
new file mode 100644
index 0000000000..3518b41403
--- /dev/null
+++ b/media/libwebp/src/enc/config_enc.c
@@ -0,0 +1,157 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Coding tools configuration
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifdef HAVE_CONFIG_H
+#include "src/webp/config.h"
+#endif
+
+#include "src/webp/encode.h"
+
+//------------------------------------------------------------------------------
+// WebPConfig
+//------------------------------------------------------------------------------
+
+int WebPConfigInitInternal(WebPConfig* config,
+ WebPPreset preset, float quality, int version) {
+ if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
+ return 0; // caller/system version mismatch!
+ }
+ if (config == NULL) return 0;
+
+ config->quality = quality;
+ config->target_size = 0;
+ config->target_PSNR = 0.;
+ config->method = 4;
+ config->sns_strength = 50;
+ config->filter_strength = 60; // mid-filtering
+ config->filter_sharpness = 0;
+ config->filter_type = 1; // default: strong (so U/V is filtered too)
+ config->partitions = 0;
+ config->segments = 4;
+ config->pass = 1;
+ config->qmin = 0;
+ config->qmax = 100;
+ config->show_compressed = 0;
+ config->preprocessing = 0;
+ config->autofilter = 0;
+ config->partition_limit = 0;
+ config->alpha_compression = 1;
+ config->alpha_filtering = 1;
+ config->alpha_quality = 100;
+ config->lossless = 0;
+ config->exact = 0;
+ config->image_hint = WEBP_HINT_DEFAULT;
+ config->emulate_jpeg_size = 0;
+ config->thread_level = 0;
+ config->low_memory = 0;
+ config->near_lossless = 100;
+ config->use_delta_palette = 0;
+ config->use_sharp_yuv = 0;
+
+ // TODO(skal): tune.
+ switch (preset) {
+ case WEBP_PRESET_PICTURE:
+ config->sns_strength = 80;
+ config->filter_sharpness = 4;
+ config->filter_strength = 35;
+ config->preprocessing &= ~2; // no dithering
+ break;
+ case WEBP_PRESET_PHOTO:
+ config->sns_strength = 80;
+ config->filter_sharpness = 3;
+ config->filter_strength = 30;
+ config->preprocessing |= 2;
+ break;
+ case WEBP_PRESET_DRAWING:
+ config->sns_strength = 25;
+ config->filter_sharpness = 6;
+ config->filter_strength = 10;
+ break;
+ case WEBP_PRESET_ICON:
+ config->sns_strength = 0;
+ config->filter_strength = 0; // disable filtering to retain sharpness
+ config->preprocessing &= ~2; // no dithering
+ break;
+ case WEBP_PRESET_TEXT:
+ config->sns_strength = 0;
+ config->filter_strength = 0; // disable filtering to retain sharpness
+ config->preprocessing &= ~2; // no dithering
+ config->segments = 2;
+ break;
+ case WEBP_PRESET_DEFAULT:
+ default:
+ break;
+ }
+ return WebPValidateConfig(config);
+}
+
+int WebPValidateConfig(const WebPConfig* config) {
+ if (config == NULL) return 0;
+ if (config->quality < 0 || config->quality > 100) return 0;
+ if (config->target_size < 0) return 0;
+ if (config->target_PSNR < 0) return 0;
+ if (config->method < 0 || config->method > 6) return 0;
+ if (config->segments < 1 || config->segments > 4) return 0;
+ if (config->sns_strength < 0 || config->sns_strength > 100) return 0;
+ if (config->filter_strength < 0 || config->filter_strength > 100) return 0;
+ if (config->filter_sharpness < 0 || config->filter_sharpness > 7) return 0;
+ if (config->filter_type < 0 || config->filter_type > 1) return 0;
+ if (config->autofilter < 0 || config->autofilter > 1) return 0;
+ if (config->pass < 1 || config->pass > 10) return 0;
+ if (config->qmin < 0 || config->qmax > 100 || config->qmin > config->qmax) {
+ return 0;
+ }
+ if (config->show_compressed < 0 || config->show_compressed > 1) return 0;
+ if (config->preprocessing < 0 || config->preprocessing > 7) return 0;
+ if (config->partitions < 0 || config->partitions > 3) return 0;
+ if (config->partition_limit < 0 || config->partition_limit > 100) return 0;
+ if (config->alpha_compression < 0) return 0;
+ if (config->alpha_filtering < 0) return 0;
+ if (config->alpha_quality < 0 || config->alpha_quality > 100) return 0;
+ if (config->lossless < 0 || config->lossless > 1) return 0;
+ if (config->near_lossless < 0 || config->near_lossless > 100) return 0;
+ if (config->image_hint >= WEBP_HINT_LAST) return 0;
+ if (config->emulate_jpeg_size < 0 || config->emulate_jpeg_size > 1) return 0;
+ if (config->thread_level < 0 || config->thread_level > 1) return 0;
+ if (config->low_memory < 0 || config->low_memory > 1) return 0;
+ if (config->exact < 0 || config->exact > 1) return 0;
+ if (config->use_delta_palette < 0 || config->use_delta_palette > 1) {
+ return 0;
+ }
+ if (config->use_sharp_yuv < 0 || config->use_sharp_yuv > 1) return 0;
+
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+
+#define MAX_LEVEL 9
+
+// Mapping between -z level and -m / -q parameter settings.
+static const struct {
+ uint8_t method_;
+ uint8_t quality_;
+} kLosslessPresets[MAX_LEVEL + 1] = {
+ { 0, 0 }, { 1, 20 }, { 2, 25 }, { 3, 30 }, { 3, 50 },
+ { 4, 50 }, { 4, 75 }, { 4, 90 }, { 5, 90 }, { 6, 100 }
+};
+
+int WebPConfigLosslessPreset(WebPConfig* config, int level) {
+ if (config == NULL || level < 0 || level > MAX_LEVEL) return 0;
+ config->lossless = 1;
+ config->method = kLosslessPresets[level].method_;
+ config->quality = kLosslessPresets[level].quality_;
+ return 1;
+}
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/cost_enc.c b/media/libwebp/src/enc/cost_enc.c
new file mode 100644
index 0000000000..48fd9bc347
--- /dev/null
+++ b/media/libwebp/src/enc/cost_enc.c
@@ -0,0 +1,342 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Cost tables for level and modes
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "src/enc/cost_enc.h"
+
+//------------------------------------------------------------------------------
+// Level cost tables
+
+// For each given level, the following table gives the pattern of contexts to
+// use for coding it (in [][0]) as well as the bit value to use for each
+// context (in [][1]).
+const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2] = {
+ {0x001, 0x000}, {0x007, 0x001}, {0x00f, 0x005},
+ {0x00f, 0x00d}, {0x033, 0x003}, {0x033, 0x003}, {0x033, 0x023},
+ {0x033, 0x023}, {0x033, 0x023}, {0x033, 0x023}, {0x0d3, 0x013},
+ {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013},
+ {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x093},
+ {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
+ {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
+ {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
+ {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
+ {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x153}
+};
+
+static int VariableLevelCost(int level, const uint8_t probas[NUM_PROBAS]) {
+ int pattern = VP8LevelCodes[level - 1][0];
+ int bits = VP8LevelCodes[level - 1][1];
+ int cost = 0;
+ int i;
+ for (i = 2; pattern; ++i) {
+ if (pattern & 1) {
+ cost += VP8BitCost(bits & 1, probas[i]);
+ }
+ bits >>= 1;
+ pattern >>= 1;
+ }
+ return cost;
+}
+
+//------------------------------------------------------------------------------
+// Pre-calc level costs once for all
+
+void VP8CalculateLevelCosts(VP8EncProba* const proba) {
+ int ctype, band, ctx;
+
+ if (!proba->dirty_) return; // nothing to do.
+
+ for (ctype = 0; ctype < NUM_TYPES; ++ctype) {
+ int n;
+ for (band = 0; band < NUM_BANDS; ++band) {
+ for (ctx = 0; ctx < NUM_CTX; ++ctx) {
+ const uint8_t* const p = proba->coeffs_[ctype][band][ctx];
+ uint16_t* const table = proba->level_cost_[ctype][band][ctx];
+ const int cost0 = (ctx > 0) ? VP8BitCost(1, p[0]) : 0;
+ const int cost_base = VP8BitCost(1, p[1]) + cost0;
+ int v;
+ table[0] = VP8BitCost(0, p[1]) + cost0;
+ for (v = 1; v <= MAX_VARIABLE_LEVEL; ++v) {
+ table[v] = cost_base + VariableLevelCost(v, p);
+ }
+ // Starting at level 67 and up, the variable part of the cost is
+ // actually constant.
+ }
+ }
+ for (n = 0; n < 16; ++n) { // replicate bands. We don't need to sentinel.
+ for (ctx = 0; ctx < NUM_CTX; ++ctx) {
+ proba->remapped_costs_[ctype][n][ctx] =
+ proba->level_cost_[ctype][VP8EncBands[n]][ctx];
+ }
+ }
+ }
+ proba->dirty_ = 0;
+}
+
+//------------------------------------------------------------------------------
+// Mode cost tables.
+
+// These are the fixed probabilities (in the coding trees) turned into bit-cost
+// by calling VP8BitCost().
+const uint16_t VP8FixedCostsUV[4] = { 302, 984, 439, 642 };
+// note: these values include the fixed VP8BitCost(1, 145) mode selection cost.
+const uint16_t VP8FixedCostsI16[4] = { 663, 919, 872, 919 };
+const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES] = {
+ { { 40, 1151, 1723, 1874, 2103, 2019, 1628, 1777, 2226, 2137 },
+ { 192, 469, 1296, 1308, 1849, 1794, 1781, 1703, 1713, 1522 },
+ { 142, 910, 762, 1684, 1849, 1576, 1460, 1305, 1801, 1657 },
+ { 559, 641, 1370, 421, 1182, 1569, 1612, 1725, 863, 1007 },
+ { 299, 1059, 1256, 1108, 636, 1068, 1581, 1883, 869, 1142 },
+ { 277, 1111, 707, 1362, 1089, 672, 1603, 1541, 1545, 1291 },
+ { 214, 781, 1609, 1303, 1632, 2229, 726, 1560, 1713, 918 },
+ { 152, 1037, 1046, 1759, 1983, 2174, 1358, 742, 1740, 1390 },
+ { 512, 1046, 1420, 753, 752, 1297, 1486, 1613, 460, 1207 },
+ { 424, 827, 1362, 719, 1462, 1202, 1199, 1476, 1199, 538 } },
+ { { 240, 402, 1134, 1491, 1659, 1505, 1517, 1555, 1979, 2099 },
+ { 467, 242, 960, 1232, 1714, 1620, 1834, 1570, 1676, 1391 },
+ { 500, 455, 463, 1507, 1699, 1282, 1564, 982, 2114, 2114 },
+ { 672, 643, 1372, 331, 1589, 1667, 1453, 1938, 996, 876 },
+ { 458, 783, 1037, 911, 738, 968, 1165, 1518, 859, 1033 },
+ { 504, 815, 504, 1139, 1219, 719, 1506, 1085, 1268, 1268 },
+ { 333, 630, 1445, 1239, 1883, 3672, 799, 1548, 1865, 598 },
+ { 399, 644, 746, 1342, 1856, 1350, 1493, 613, 1855, 1015 },
+ { 622, 749, 1205, 608, 1066, 1408, 1290, 1406, 546, 971 },
+ { 500, 753, 1041, 668, 1230, 1617, 1297, 1425, 1383, 523 } },
+ { { 394, 553, 523, 1502, 1536, 981, 1608, 1142, 1666, 2181 },
+ { 655, 430, 375, 1411, 1861, 1220, 1677, 1135, 1978, 1553 },
+ { 690, 640, 245, 1954, 2070, 1194, 1528, 982, 1972, 2232 },
+ { 559, 834, 741, 867, 1131, 980, 1225, 852, 1092, 784 },
+ { 690, 875, 516, 959, 673, 894, 1056, 1190, 1528, 1126 },
+ { 740, 951, 384, 1277, 1177, 492, 1579, 1155, 1846, 1513 },
+ { 323, 775, 1062, 1776, 3062, 1274, 813, 1188, 1372, 655 },
+ { 488, 971, 484, 1767, 1515, 1775, 1115, 503, 1539, 1461 },
+ { 740, 1006, 998, 709, 851, 1230, 1337, 788, 741, 721 },
+ { 522, 1073, 573, 1045, 1346, 887, 1046, 1146, 1203, 697 } },
+ { { 105, 864, 1442, 1009, 1934, 1840, 1519, 1920, 1673, 1579 },
+ { 534, 305, 1193, 683, 1388, 2164, 1802, 1894, 1264, 1170 },
+ { 305, 518, 877, 1108, 1426, 3215, 1425, 1064, 1320, 1242 },
+ { 683, 732, 1927, 257, 1493, 2048, 1858, 1552, 1055, 947 },
+ { 394, 814, 1024, 660, 959, 1556, 1282, 1289, 893, 1047 },
+ { 528, 615, 996, 940, 1201, 635, 1094, 2515, 803, 1358 },
+ { 347, 614, 1609, 1187, 3133, 1345, 1007, 1339, 1017, 667 },
+ { 218, 740, 878, 1605, 3650, 3650, 1345, 758, 1357, 1617 },
+ { 672, 750, 1541, 558, 1257, 1599, 1870, 2135, 402, 1087 },
+ { 592, 684, 1161, 430, 1092, 1497, 1475, 1489, 1095, 822 } },
+ { { 228, 1056, 1059, 1368, 752, 982, 1512, 1518, 987, 1782 },
+ { 494, 514, 818, 942, 965, 892, 1610, 1356, 1048, 1363 },
+ { 512, 648, 591, 1042, 761, 991, 1196, 1454, 1309, 1463 },
+ { 683, 749, 1043, 676, 841, 1396, 1133, 1138, 654, 939 },
+ { 622, 1101, 1126, 994, 361, 1077, 1203, 1318, 877, 1219 },
+ { 631, 1068, 857, 1650, 651, 477, 1650, 1419, 828, 1170 },
+ { 555, 727, 1068, 1335, 3127, 1339, 820, 1331, 1077, 429 },
+ { 504, 879, 624, 1398, 889, 889, 1392, 808, 891, 1406 },
+ { 683, 1602, 1289, 977, 578, 983, 1280, 1708, 406, 1122 },
+ { 399, 865, 1433, 1070, 1072, 764, 968, 1477, 1223, 678 } },
+ { { 333, 760, 935, 1638, 1010, 529, 1646, 1410, 1472, 2219 },
+ { 512, 494, 750, 1160, 1215, 610, 1870, 1868, 1628, 1169 },
+ { 572, 646, 492, 1934, 1208, 603, 1580, 1099, 1398, 1995 },
+ { 786, 789, 942, 581, 1018, 951, 1599, 1207, 731, 768 },
+ { 690, 1015, 672, 1078, 582, 504, 1693, 1438, 1108, 2897 },
+ { 768, 1267, 571, 2005, 1243, 244, 2881, 1380, 1786, 1453 },
+ { 452, 899, 1293, 903, 1311, 3100, 465, 1311, 1319, 813 },
+ { 394, 927, 942, 1103, 1358, 1104, 946, 593, 1363, 1109 },
+ { 559, 1005, 1007, 1016, 658, 1173, 1021, 1164, 623, 1028 },
+ { 564, 796, 632, 1005, 1014, 863, 2316, 1268, 938, 764 } },
+ { { 266, 606, 1098, 1228, 1497, 1243, 948, 1030, 1734, 1461 },
+ { 366, 585, 901, 1060, 1407, 1247, 876, 1134, 1620, 1054 },
+ { 452, 565, 542, 1729, 1479, 1479, 1016, 886, 2938, 1150 },
+ { 555, 1088, 1533, 950, 1354, 895, 834, 1019, 1021, 496 },
+ { 704, 815, 1193, 971, 973, 640, 1217, 2214, 832, 578 },
+ { 672, 1245, 579, 871, 875, 774, 872, 1273, 1027, 949 },
+ { 296, 1134, 2050, 1784, 1636, 3425, 442, 1550, 2076, 722 },
+ { 342, 982, 1259, 1846, 1848, 1848, 622, 568, 1847, 1052 },
+ { 555, 1064, 1304, 828, 746, 1343, 1075, 1329, 1078, 494 },
+ { 288, 1167, 1285, 1174, 1639, 1639, 833, 2254, 1304, 509 } },
+ { { 342, 719, 767, 1866, 1757, 1270, 1246, 550, 1746, 2151 },
+ { 483, 653, 694, 1509, 1459, 1410, 1218, 507, 1914, 1266 },
+ { 488, 757, 447, 2979, 1813, 1268, 1654, 539, 1849, 2109 },
+ { 522, 1097, 1085, 851, 1365, 1111, 851, 901, 961, 605 },
+ { 709, 716, 841, 728, 736, 945, 941, 862, 2845, 1057 },
+ { 512, 1323, 500, 1336, 1083, 681, 1342, 717, 1604, 1350 },
+ { 452, 1155, 1372, 1900, 1501, 3290, 311, 944, 1919, 922 },
+ { 403, 1520, 977, 2132, 1733, 3522, 1076, 276, 3335, 1547 },
+ { 559, 1374, 1101, 615, 673, 2462, 974, 795, 984, 984 },
+ { 547, 1122, 1062, 812, 1410, 951, 1140, 622, 1268, 651 } },
+ { { 165, 982, 1235, 938, 1334, 1366, 1659, 1578, 964, 1612 },
+ { 592, 422, 925, 847, 1139, 1112, 1387, 2036, 861, 1041 },
+ { 403, 837, 732, 770, 941, 1658, 1250, 809, 1407, 1407 },
+ { 896, 874, 1071, 381, 1568, 1722, 1437, 2192, 480, 1035 },
+ { 640, 1098, 1012, 1032, 684, 1382, 1581, 2106, 416, 865 },
+ { 559, 1005, 819, 914, 710, 770, 1418, 920, 838, 1435 },
+ { 415, 1258, 1245, 870, 1278, 3067, 770, 1021, 1287, 522 },
+ { 406, 990, 601, 1009, 1265, 1265, 1267, 759, 1017, 1277 },
+ { 968, 1182, 1329, 788, 1032, 1292, 1705, 1714, 203, 1403 },
+ { 732, 877, 1279, 471, 901, 1161, 1545, 1294, 755, 755 } },
+ { { 111, 931, 1378, 1185, 1933, 1648, 1148, 1714, 1873, 1307 },
+ { 406, 414, 1030, 1023, 1910, 1404, 1313, 1647, 1509, 793 },
+ { 342, 640, 575, 1088, 1241, 1349, 1161, 1350, 1756, 1502 },
+ { 559, 766, 1185, 357, 1682, 1428, 1329, 1897, 1219, 802 },
+ { 473, 909, 1164, 771, 719, 2508, 1427, 1432, 722, 782 },
+ { 342, 892, 785, 1145, 1150, 794, 1296, 1550, 973, 1057 },
+ { 208, 1036, 1326, 1343, 1606, 3395, 815, 1455, 1618, 712 },
+ { 228, 928, 890, 1046, 3499, 1711, 994, 829, 1720, 1318 },
+ { 768, 724, 1058, 636, 991, 1075, 1319, 1324, 616, 825 },
+ { 305, 1167, 1358, 899, 1587, 1587, 987, 1988, 1332, 501 } }
+};
+
+//------------------------------------------------------------------------------
+// helper functions for residuals struct VP8Residual.
+
+void VP8InitResidual(int first, int coeff_type,
+ VP8Encoder* const enc, VP8Residual* const res) {
+ res->coeff_type = coeff_type;
+ res->prob = enc->proba_.coeffs_[coeff_type];
+ res->stats = enc->proba_.stats_[coeff_type];
+ res->costs = enc->proba_.remapped_costs_[coeff_type];
+ res->first = first;
+}
+
+//------------------------------------------------------------------------------
+// Mode costs
+
+int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]) {
+ const int x = (it->i4_ & 3), y = (it->i4_ >> 2);
+ VP8Residual res;
+ VP8Encoder* const enc = it->enc_;
+ int R = 0;
+ int ctx;
+
+ VP8InitResidual(0, 3, enc, &res);
+ ctx = it->top_nz_[x] + it->left_nz_[y];
+ VP8SetResidualCoeffs(levels, &res);
+ R += VP8GetResidualCost(ctx, &res);
+ return R;
+}
+
+int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd) {
+ VP8Residual res;
+ VP8Encoder* const enc = it->enc_;
+ int x, y;
+ int R = 0;
+
+ VP8IteratorNzToBytes(it); // re-import the non-zero context
+
+ // DC
+ VP8InitResidual(0, 1, enc, &res);
+ VP8SetResidualCoeffs(rd->y_dc_levels, &res);
+ R += VP8GetResidualCost(it->top_nz_[8] + it->left_nz_[8], &res);
+
+ // AC
+ VP8InitResidual(1, 0, enc, &res);
+ for (y = 0; y < 4; ++y) {
+ for (x = 0; x < 4; ++x) {
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ VP8SetResidualCoeffs(rd->y_ac_levels[x + y * 4], &res);
+ R += VP8GetResidualCost(ctx, &res);
+ it->top_nz_[x] = it->left_nz_[y] = (res.last >= 0);
+ }
+ }
+ return R;
+}
+
+int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd) {
+ VP8Residual res;
+ VP8Encoder* const enc = it->enc_;
+ int ch, x, y;
+ int R = 0;
+
+ VP8IteratorNzToBytes(it); // re-import the non-zero context
+
+ VP8InitResidual(0, 2, enc, &res);
+ for (ch = 0; ch <= 2; ch += 2) {
+ for (y = 0; y < 2; ++y) {
+ for (x = 0; x < 2; ++x) {
+ const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
+ VP8SetResidualCoeffs(rd->uv_levels[ch * 2 + x + y * 2], &res);
+ R += VP8GetResidualCost(ctx, &res);
+ it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] = (res.last >= 0);
+ }
+ }
+ }
+ return R;
+}
+
+
+//------------------------------------------------------------------------------
+// Recording of token probabilities.
+
+// We keep the table-free variant around for reference, in case.
+#define USE_LEVEL_CODE_TABLE
+
+// Simulate block coding, but only record statistics.
+// Note: no need to record the fixed probas.
+int VP8RecordCoeffs(int ctx, const VP8Residual* const res) {
+ int n = res->first;
+ // should be stats[VP8EncBands[n]], but it's equivalent for n=0 or 1
+ proba_t* s = res->stats[n][ctx];
+ if (res->last < 0) {
+ VP8RecordStats(0, s + 0);
+ return 0;
+ }
+ while (n <= res->last) {
+ int v;
+ VP8RecordStats(1, s + 0); // order of record doesn't matter
+ while ((v = res->coeffs[n++]) == 0) {
+ VP8RecordStats(0, s + 1);
+ s = res->stats[VP8EncBands[n]][0];
+ }
+ VP8RecordStats(1, s + 1);
+ if (!VP8RecordStats(2u < (unsigned int)(v + 1), s + 2)) { // v = -1 or 1
+ s = res->stats[VP8EncBands[n]][1];
+ } else {
+ v = abs(v);
+#if !defined(USE_LEVEL_CODE_TABLE)
+ if (!VP8RecordStats(v > 4, s + 3)) {
+ if (VP8RecordStats(v != 2, s + 4))
+ VP8RecordStats(v == 4, s + 5);
+ } else if (!VP8RecordStats(v > 10, s + 6)) {
+ VP8RecordStats(v > 6, s + 7);
+ } else if (!VP8RecordStats((v >= 3 + (8 << 2)), s + 8)) {
+ VP8RecordStats((v >= 3 + (8 << 1)), s + 9);
+ } else {
+ VP8RecordStats((v >= 3 + (8 << 3)), s + 10);
+ }
+#else
+ if (v > MAX_VARIABLE_LEVEL) {
+ v = MAX_VARIABLE_LEVEL;
+ }
+
+ {
+ const int bits = VP8LevelCodes[v - 1][1];
+ int pattern = VP8LevelCodes[v - 1][0];
+ int i;
+ for (i = 0; (pattern >>= 1) != 0; ++i) {
+ const int mask = 2 << i;
+ if (pattern & 1) VP8RecordStats(!!(bits & mask), s + 3 + i);
+ }
+ }
+#endif
+ s = res->stats[VP8EncBands[n]][2];
+ }
+ }
+ if (n < 16) VP8RecordStats(0, s + 0);
+ return 1;
+}
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/cost_enc.h b/media/libwebp/src/enc/cost_enc.h
new file mode 100644
index 0000000000..a4b177b342
--- /dev/null
+++ b/media/libwebp/src/enc/cost_enc.h
@@ -0,0 +1,82 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Cost tables for level and modes.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_ENC_COST_ENC_H_
+#define WEBP_ENC_COST_ENC_H_
+
+#include <assert.h>
+#include <stdlib.h>
+#include "src/enc/vp8i_enc.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// On-the-fly info about the current set of residuals. Handy to avoid
+// passing zillions of params.
+typedef struct VP8Residual VP8Residual;
+struct VP8Residual {
+ int first;
+ int last;
+ const int16_t* coeffs;
+
+ int coeff_type;
+ ProbaArray* prob;
+ StatsArray* stats;
+ CostArrayPtr costs;
+};
+
+void VP8InitResidual(int first, int coeff_type,
+ VP8Encoder* const enc, VP8Residual* const res);
+
+int VP8RecordCoeffs(int ctx, const VP8Residual* const res);
+
+// Record proba context used.
+static WEBP_INLINE int VP8RecordStats(int bit, proba_t* const stats) {
+ proba_t p = *stats;
+ // An overflow is inbound. Note we handle this at 0xfffe0000u instead of
+ // 0xffff0000u to make sure p + 1u does not overflow.
+ if (p >= 0xfffe0000u) {
+ p = ((p + 1u) >> 1) & 0x7fff7fffu; // -> divide the stats by 2.
+ }
+ // record bit count (lower 16 bits) and increment total count (upper 16 bits).
+ p += 0x00010000u + bit;
+ *stats = p;
+ return bit;
+}
+
+// Cost of coding one event with probability 'proba'.
+static WEBP_INLINE int VP8BitCost(int bit, uint8_t proba) {
+ return !bit ? VP8EntropyCost[proba] : VP8EntropyCost[255 - proba];
+}
+
+// Level cost calculations
+extern const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2];
+void VP8CalculateLevelCosts(VP8EncProba* const proba);
+static WEBP_INLINE int VP8LevelCost(const uint16_t* const table, int level) {
+ return VP8LevelFixedCosts[level]
+ + table[(level > MAX_VARIABLE_LEVEL) ? MAX_VARIABLE_LEVEL : level];
+}
+
+// Mode costs
+extern const uint16_t VP8FixedCostsUV[4];
+extern const uint16_t VP8FixedCostsI16[4];
+extern const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES];
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // WEBP_ENC_COST_ENC_H_
diff --git a/media/libwebp/src/enc/filter_enc.c b/media/libwebp/src/enc/filter_enc.c
new file mode 100644
index 0000000000..580800bfb8
--- /dev/null
+++ b/media/libwebp/src/enc/filter_enc.c
@@ -0,0 +1,235 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Selecting filter level
+//
+// Author: somnath@google.com (Somnath Banerjee)
+
+#include <assert.h>
+#include "src/enc/vp8i_enc.h"
+#include "src/dsp/dsp.h"
+
+// This table gives, for a given sharpness, the filtering strength to be
+// used (at least) in order to filter a given edge step delta.
+// This is constructed by brute force inspection: for all delta, we iterate
+// over all possible filtering strength / thresh until needs_filter() returns
+// true.
+#define MAX_DELTA_SIZE 64
+static const uint8_t kLevelsFromDelta[8][MAX_DELTA_SIZE] = {
+ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63 },
+ { 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 17, 18,
+ 20, 21, 23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42,
+ 44, 45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 13, 14, 16, 17, 19,
+ 20, 22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 40, 41, 43,
+ 44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 13, 15, 16, 18, 19,
+ 21, 22, 24, 25, 27, 28, 30, 31, 33, 34, 36, 37, 39, 40, 42, 43,
+ 45, 46, 48, 49, 51, 52, 54, 55, 57, 58, 60, 61, 63, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 14, 15, 17, 18, 20,
+ 21, 23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44,
+ 45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 17, 19, 20,
+ 22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 40, 41, 43, 44,
+ 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 63, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 18, 19, 21,
+ 22, 24, 25, 27, 28, 30, 31, 33, 34, 36, 37, 39, 40, 42, 43, 45,
+ 46, 48, 49, 51, 52, 54, 55, 57, 58, 60, 61, 63, 63, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
+ { 0, 1, 2, 4, 5, 7, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21,
+ 23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44, 45,
+ 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63, 63, 63,
+ 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 }
+};
+
+int VP8FilterStrengthFromDelta(int sharpness, int delta) {
+ const int pos = (delta < MAX_DELTA_SIZE) ? delta : MAX_DELTA_SIZE - 1;
+ assert(sharpness >= 0 && sharpness <= 7);
+ return kLevelsFromDelta[sharpness][pos];
+}
+
+//------------------------------------------------------------------------------
+// Paragraph 15.4: compute the inner-edge filtering strength
+
+#if !defined(WEBP_REDUCE_SIZE)
+
+static int GetILevel(int sharpness, int level) {
+ if (sharpness > 0) {
+ if (sharpness > 4) {
+ level >>= 2;
+ } else {
+ level >>= 1;
+ }
+ if (level > 9 - sharpness) {
+ level = 9 - sharpness;
+ }
+ }
+ if (level < 1) level = 1;
+ return level;
+}
+
+static void DoFilter(const VP8EncIterator* const it, int level) {
+ const VP8Encoder* const enc = it->enc_;
+ const int ilevel = GetILevel(enc->config_->filter_sharpness, level);
+ const int limit = 2 * level + ilevel;
+
+ uint8_t* const y_dst = it->yuv_out2_ + Y_OFF_ENC;
+ uint8_t* const u_dst = it->yuv_out2_ + U_OFF_ENC;
+ uint8_t* const v_dst = it->yuv_out2_ + V_OFF_ENC;
+
+ // copy current block to yuv_out2_
+ memcpy(y_dst, it->yuv_out_, YUV_SIZE_ENC * sizeof(uint8_t));
+
+ if (enc->filter_hdr_.simple_ == 1) { // simple
+ VP8SimpleHFilter16i(y_dst, BPS, limit);
+ VP8SimpleVFilter16i(y_dst, BPS, limit);
+ } else { // complex
+ const int hev_thresh = (level >= 40) ? 2 : (level >= 15) ? 1 : 0;
+ VP8HFilter16i(y_dst, BPS, limit, ilevel, hev_thresh);
+ VP8HFilter8i(u_dst, v_dst, BPS, limit, ilevel, hev_thresh);
+ VP8VFilter16i(y_dst, BPS, limit, ilevel, hev_thresh);
+ VP8VFilter8i(u_dst, v_dst, BPS, limit, ilevel, hev_thresh);
+ }
+}
+
+//------------------------------------------------------------------------------
+// SSIM metric for one macroblock
+
+static double GetMBSSIM(const uint8_t* yuv1, const uint8_t* yuv2) {
+ int x, y;
+ double sum = 0.;
+
+ // compute SSIM in a 10 x 10 window
+ for (y = VP8_SSIM_KERNEL; y < 16 - VP8_SSIM_KERNEL; y++) {
+ for (x = VP8_SSIM_KERNEL; x < 16 - VP8_SSIM_KERNEL; x++) {
+ sum += VP8SSIMGetClipped(yuv1 + Y_OFF_ENC, BPS, yuv2 + Y_OFF_ENC, BPS,
+ x, y, 16, 16);
+ }
+ }
+ for (x = 1; x < 7; x++) {
+ for (y = 1; y < 7; y++) {
+ sum += VP8SSIMGetClipped(yuv1 + U_OFF_ENC, BPS, yuv2 + U_OFF_ENC, BPS,
+ x, y, 8, 8);
+ sum += VP8SSIMGetClipped(yuv1 + V_OFF_ENC, BPS, yuv2 + V_OFF_ENC, BPS,
+ x, y, 8, 8);
+ }
+ }
+ return sum;
+}
+
+#endif // !defined(WEBP_REDUCE_SIZE)
+
+//------------------------------------------------------------------------------
+// Exposed APIs: Encoder should call the following 3 functions to adjust
+// loop filter strength
+
+void VP8InitFilter(VP8EncIterator* const it) {
+#if !defined(WEBP_REDUCE_SIZE)
+ if (it->lf_stats_ != NULL) {
+ int s, i;
+ for (s = 0; s < NUM_MB_SEGMENTS; s++) {
+ for (i = 0; i < MAX_LF_LEVELS; i++) {
+ (*it->lf_stats_)[s][i] = 0;
+ }
+ }
+ VP8SSIMDspInit();
+ }
+#else
+ (void)it;
+#endif
+}
+
+void VP8StoreFilterStats(VP8EncIterator* const it) {
+#if !defined(WEBP_REDUCE_SIZE)
+ int d;
+ VP8Encoder* const enc = it->enc_;
+ const int s = it->mb_->segment_;
+ const int level0 = enc->dqm_[s].fstrength_;
+
+ // explore +/-quant range of values around level0
+ const int delta_min = -enc->dqm_[s].quant_;
+ const int delta_max = enc->dqm_[s].quant_;
+ const int step_size = (delta_max - delta_min >= 4) ? 4 : 1;
+
+ if (it->lf_stats_ == NULL) return;
+
+ // NOTE: Currently we are applying filter only across the sublock edges
+ // There are two reasons for that.
+ // 1. Applying filter on macro block edges will change the pixels in
+ // the left and top macro blocks. That will be hard to restore
+ // 2. Macro Blocks on the bottom and right are not yet compressed. So we
+ // cannot apply filter on the right and bottom macro block edges.
+ if (it->mb_->type_ == 1 && it->mb_->skip_) return;
+
+ // Always try filter level zero
+ (*it->lf_stats_)[s][0] += GetMBSSIM(it->yuv_in_, it->yuv_out_);
+
+ for (d = delta_min; d <= delta_max; d += step_size) {
+ const int level = level0 + d;
+ if (level <= 0 || level >= MAX_LF_LEVELS) {
+ continue;
+ }
+ DoFilter(it, level);
+ (*it->lf_stats_)[s][level] += GetMBSSIM(it->yuv_in_, it->yuv_out2_);
+ }
+#else // defined(WEBP_REDUCE_SIZE)
+ (void)it;
+#endif // !defined(WEBP_REDUCE_SIZE)
+}
+
+void VP8AdjustFilterStrength(VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+#if !defined(WEBP_REDUCE_SIZE)
+ if (it->lf_stats_ != NULL) {
+ int s;
+ for (s = 0; s < NUM_MB_SEGMENTS; s++) {
+ int i, best_level = 0;
+ // Improvement over filter level 0 should be at least 1e-5 (relatively)
+ double best_v = 1.00001 * (*it->lf_stats_)[s][0];
+ for (i = 1; i < MAX_LF_LEVELS; i++) {
+ const double v = (*it->lf_stats_)[s][i];
+ if (v > best_v) {
+ best_v = v;
+ best_level = i;
+ }
+ }
+ enc->dqm_[s].fstrength_ = best_level;
+ }
+ return;
+ }
+#endif // !defined(WEBP_REDUCE_SIZE)
+ if (enc->config_->filter_strength > 0) {
+ int max_level = 0;
+ int s;
+ for (s = 0; s < NUM_MB_SEGMENTS; s++) {
+ VP8SegmentInfo* const dqm = &enc->dqm_[s];
+ // this '>> 3' accounts for some inverse WHT scaling
+ const int delta = (dqm->max_edge_ * dqm->y2_.q_[1]) >> 3;
+ const int level =
+ VP8FilterStrengthFromDelta(enc->filter_hdr_.sharpness_, delta);
+ if (level > dqm->fstrength_) {
+ dqm->fstrength_ = level;
+ }
+ if (max_level < dqm->fstrength_) {
+ max_level = dqm->fstrength_;
+ }
+ }
+ enc->filter_hdr_.level_ = max_level;
+ }
+}
+
+// -----------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/frame_enc.c b/media/libwebp/src/enc/frame_enc.c
new file mode 100644
index 0000000000..b93d9e5b99
--- /dev/null
+++ b/media/libwebp/src/enc/frame_enc.c
@@ -0,0 +1,899 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// frame coding and analysis
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <string.h>
+#include <math.h>
+
+#include "src/enc/cost_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/dsp/dsp.h"
+#include "src/webp/format_constants.h" // RIFF constants
+
+#define SEGMENT_VISU 0
+#define DEBUG_SEARCH 0 // useful to track search convergence
+
+//------------------------------------------------------------------------------
+// multi-pass convergence
+
+#define HEADER_SIZE_ESTIMATE (RIFF_HEADER_SIZE + CHUNK_HEADER_SIZE + \
+ VP8_FRAME_HEADER_SIZE)
+#define DQ_LIMIT 0.4 // convergence is considered reached if dq < DQ_LIMIT
+// we allow 2k of extra head-room in PARTITION0 limit.
+#define PARTITION0_SIZE_LIMIT ((VP8_MAX_PARTITION0_SIZE - 2048ULL) << 11)
+
+static float Clamp(float v, float min, float max) {
+ return (v < min) ? min : (v > max) ? max : v;
+}
+
+typedef struct { // struct for organizing convergence in either size or PSNR
+ int is_first;
+ float dq;
+ float q, last_q;
+ float qmin, qmax;
+ double value, last_value; // PSNR or size
+ double target;
+ int do_size_search;
+} PassStats;
+
+static int InitPassStats(const VP8Encoder* const enc, PassStats* const s) {
+ const uint64_t target_size = (uint64_t)enc->config_->target_size;
+ const int do_size_search = (target_size != 0);
+ const float target_PSNR = enc->config_->target_PSNR;
+
+ s->is_first = 1;
+ s->dq = 10.f;
+ s->qmin = 1.f * enc->config_->qmin;
+ s->qmax = 1.f * enc->config_->qmax;
+ s->q = s->last_q = Clamp(enc->config_->quality, s->qmin, s->qmax);
+ s->target = do_size_search ? (double)target_size
+ : (target_PSNR > 0.) ? target_PSNR
+ : 40.; // default, just in case
+ s->value = s->last_value = 0.;
+ s->do_size_search = do_size_search;
+ return do_size_search;
+}
+
+static float ComputeNextQ(PassStats* const s) {
+ float dq;
+ if (s->is_first) {
+ dq = (s->value > s->target) ? -s->dq : s->dq;
+ s->is_first = 0;
+ } else if (s->value != s->last_value) {
+ const double slope = (s->target - s->value) / (s->last_value - s->value);
+ dq = (float)(slope * (s->last_q - s->q));
+ } else {
+ dq = 0.; // we're done?!
+ }
+ // Limit variable to avoid large swings.
+ s->dq = Clamp(dq, -30.f, 30.f);
+ s->last_q = s->q;
+ s->last_value = s->value;
+ s->q = Clamp(s->q + s->dq, s->qmin, s->qmax);
+ return s->q;
+}
+
+//------------------------------------------------------------------------------
+// Tables for level coding
+
+const uint8_t VP8Cat3[] = { 173, 148, 140 };
+const uint8_t VP8Cat4[] = { 176, 155, 140, 135 };
+const uint8_t VP8Cat5[] = { 180, 157, 141, 134, 130 };
+const uint8_t VP8Cat6[] =
+ { 254, 254, 243, 230, 196, 177, 153, 140, 133, 130, 129 };
+
+//------------------------------------------------------------------------------
+// Reset the statistics about: number of skips, token proba, level cost,...
+
+static void ResetStats(VP8Encoder* const enc) {
+ VP8EncProba* const proba = &enc->proba_;
+ VP8CalculateLevelCosts(proba);
+ proba->nb_skip_ = 0;
+}
+
+//------------------------------------------------------------------------------
+// Skip decision probability
+
+#define SKIP_PROBA_THRESHOLD 250 // value below which using skip_proba is OK.
+
+static int CalcSkipProba(uint64_t nb, uint64_t total) {
+ return (int)(total ? (total - nb) * 255 / total : 255);
+}
+
+// Returns the bit-cost for coding the skip probability.
+static int FinalizeSkipProba(VP8Encoder* const enc) {
+ VP8EncProba* const proba = &enc->proba_;
+ const int nb_mbs = enc->mb_w_ * enc->mb_h_;
+ const int nb_events = proba->nb_skip_;
+ int size;
+ proba->skip_proba_ = CalcSkipProba(nb_events, nb_mbs);
+ proba->use_skip_proba_ = (proba->skip_proba_ < SKIP_PROBA_THRESHOLD);
+ size = 256; // 'use_skip_proba' bit
+ if (proba->use_skip_proba_) {
+ size += nb_events * VP8BitCost(1, proba->skip_proba_)
+ + (nb_mbs - nb_events) * VP8BitCost(0, proba->skip_proba_);
+ size += 8 * 256; // cost of signaling the skip_proba_ itself.
+ }
+ return size;
+}
+
+// Collect statistics and deduce probabilities for next coding pass.
+// Return the total bit-cost for coding the probability updates.
+static int CalcTokenProba(int nb, int total) {
+ assert(nb <= total);
+ return nb ? (255 - nb * 255 / total) : 255;
+}
+
+// Cost of coding 'nb' 1's and 'total-nb' 0's using 'proba' probability.
+static int BranchCost(int nb, int total, int proba) {
+ return nb * VP8BitCost(1, proba) + (total - nb) * VP8BitCost(0, proba);
+}
+
+static void ResetTokenStats(VP8Encoder* const enc) {
+ VP8EncProba* const proba = &enc->proba_;
+ memset(proba->stats_, 0, sizeof(proba->stats_));
+}
+
+static int FinalizeTokenProbas(VP8EncProba* const proba) {
+ int has_changed = 0;
+ int size = 0;
+ int t, b, c, p;
+ for (t = 0; t < NUM_TYPES; ++t) {
+ for (b = 0; b < NUM_BANDS; ++b) {
+ for (c = 0; c < NUM_CTX; ++c) {
+ for (p = 0; p < NUM_PROBAS; ++p) {
+ const proba_t stats = proba->stats_[t][b][c][p];
+ const int nb = (stats >> 0) & 0xffff;
+ const int total = (stats >> 16) & 0xffff;
+ const int update_proba = VP8CoeffsUpdateProba[t][b][c][p];
+ const int old_p = VP8CoeffsProba0[t][b][c][p];
+ const int new_p = CalcTokenProba(nb, total);
+ const int old_cost = BranchCost(nb, total, old_p)
+ + VP8BitCost(0, update_proba);
+ const int new_cost = BranchCost(nb, total, new_p)
+ + VP8BitCost(1, update_proba)
+ + 8 * 256;
+ const int use_new_p = (old_cost > new_cost);
+ size += VP8BitCost(use_new_p, update_proba);
+ if (use_new_p) { // only use proba that seem meaningful enough.
+ proba->coeffs_[t][b][c][p] = new_p;
+ has_changed |= (new_p != old_p);
+ size += 8 * 256;
+ } else {
+ proba->coeffs_[t][b][c][p] = old_p;
+ }
+ }
+ }
+ }
+ }
+ proba->dirty_ = has_changed;
+ return size;
+}
+
+//------------------------------------------------------------------------------
+// Finalize Segment probability based on the coding tree
+
+static int GetProba(int a, int b) {
+ const int total = a + b;
+ return (total == 0) ? 255 // that's the default probability.
+ : (255 * a + total / 2) / total; // rounded proba
+}
+
+static void ResetSegments(VP8Encoder* const enc) {
+ int n;
+ for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
+ enc->mb_info_[n].segment_ = 0;
+ }
+}
+
+static void SetSegmentProbas(VP8Encoder* const enc) {
+ int p[NUM_MB_SEGMENTS] = { 0 };
+ int n;
+
+ for (n = 0; n < enc->mb_w_ * enc->mb_h_; ++n) {
+ const VP8MBInfo* const mb = &enc->mb_info_[n];
+ ++p[mb->segment_];
+ }
+#if !defined(WEBP_DISABLE_STATS)
+ if (enc->pic_->stats != NULL) {
+ for (n = 0; n < NUM_MB_SEGMENTS; ++n) {
+ enc->pic_->stats->segment_size[n] = p[n];
+ }
+ }
+#endif
+ if (enc->segment_hdr_.num_segments_ > 1) {
+ uint8_t* const probas = enc->proba_.segments_;
+ probas[0] = GetProba(p[0] + p[1], p[2] + p[3]);
+ probas[1] = GetProba(p[0], p[1]);
+ probas[2] = GetProba(p[2], p[3]);
+
+ enc->segment_hdr_.update_map_ =
+ (probas[0] != 255) || (probas[1] != 255) || (probas[2] != 255);
+ if (!enc->segment_hdr_.update_map_) ResetSegments(enc);
+ enc->segment_hdr_.size_ =
+ p[0] * (VP8BitCost(0, probas[0]) + VP8BitCost(0, probas[1])) +
+ p[1] * (VP8BitCost(0, probas[0]) + VP8BitCost(1, probas[1])) +
+ p[2] * (VP8BitCost(1, probas[0]) + VP8BitCost(0, probas[2])) +
+ p[3] * (VP8BitCost(1, probas[0]) + VP8BitCost(1, probas[2]));
+ } else {
+ enc->segment_hdr_.update_map_ = 0;
+ enc->segment_hdr_.size_ = 0;
+ }
+}
+
+//------------------------------------------------------------------------------
+// Coefficient coding
+
+static int PutCoeffs(VP8BitWriter* const bw, int ctx, const VP8Residual* res) {
+ int n = res->first;
+ // should be prob[VP8EncBands[n]], but it's equivalent for n=0 or 1
+ const uint8_t* p = res->prob[n][ctx];
+ if (!VP8PutBit(bw, res->last >= 0, p[0])) {
+ return 0;
+ }
+
+ while (n < 16) {
+ const int c = res->coeffs[n++];
+ const int sign = c < 0;
+ int v = sign ? -c : c;
+ if (!VP8PutBit(bw, v != 0, p[1])) {
+ p = res->prob[VP8EncBands[n]][0];
+ continue;
+ }
+ if (!VP8PutBit(bw, v > 1, p[2])) {
+ p = res->prob[VP8EncBands[n]][1];
+ } else {
+ if (!VP8PutBit(bw, v > 4, p[3])) {
+ if (VP8PutBit(bw, v != 2, p[4])) {
+ VP8PutBit(bw, v == 4, p[5]);
+ }
+ } else if (!VP8PutBit(bw, v > 10, p[6])) {
+ if (!VP8PutBit(bw, v > 6, p[7])) {
+ VP8PutBit(bw, v == 6, 159);
+ } else {
+ VP8PutBit(bw, v >= 9, 165);
+ VP8PutBit(bw, !(v & 1), 145);
+ }
+ } else {
+ int mask;
+ const uint8_t* tab;
+ if (v < 3 + (8 << 1)) { // VP8Cat3 (3b)
+ VP8PutBit(bw, 0, p[8]);
+ VP8PutBit(bw, 0, p[9]);
+ v -= 3 + (8 << 0);
+ mask = 1 << 2;
+ tab = VP8Cat3;
+ } else if (v < 3 + (8 << 2)) { // VP8Cat4 (4b)
+ VP8PutBit(bw, 0, p[8]);
+ VP8PutBit(bw, 1, p[9]);
+ v -= 3 + (8 << 1);
+ mask = 1 << 3;
+ tab = VP8Cat4;
+ } else if (v < 3 + (8 << 3)) { // VP8Cat5 (5b)
+ VP8PutBit(bw, 1, p[8]);
+ VP8PutBit(bw, 0, p[10]);
+ v -= 3 + (8 << 2);
+ mask = 1 << 4;
+ tab = VP8Cat5;
+ } else { // VP8Cat6 (11b)
+ VP8PutBit(bw, 1, p[8]);
+ VP8PutBit(bw, 1, p[10]);
+ v -= 3 + (8 << 3);
+ mask = 1 << 10;
+ tab = VP8Cat6;
+ }
+ while (mask) {
+ VP8PutBit(bw, !!(v & mask), *tab++);
+ mask >>= 1;
+ }
+ }
+ p = res->prob[VP8EncBands[n]][2];
+ }
+ VP8PutBitUniform(bw, sign);
+ if (n == 16 || !VP8PutBit(bw, n <= res->last, p[0])) {
+ return 1; // EOB
+ }
+ }
+ return 1;
+}
+
+static void CodeResiduals(VP8BitWriter* const bw, VP8EncIterator* const it,
+ const VP8ModeScore* const rd) {
+ int x, y, ch;
+ VP8Residual res;
+ uint64_t pos1, pos2, pos3;
+ const int i16 = (it->mb_->type_ == 1);
+ const int segment = it->mb_->segment_;
+ VP8Encoder* const enc = it->enc_;
+
+ VP8IteratorNzToBytes(it);
+
+ pos1 = VP8BitWriterPos(bw);
+ if (i16) {
+ VP8InitResidual(0, 1, enc, &res);
+ VP8SetResidualCoeffs(rd->y_dc_levels, &res);
+ it->top_nz_[8] = it->left_nz_[8] =
+ PutCoeffs(bw, it->top_nz_[8] + it->left_nz_[8], &res);
+ VP8InitResidual(1, 0, enc, &res);
+ } else {
+ VP8InitResidual(0, 3, enc, &res);
+ }
+
+ // luma-AC
+ for (y = 0; y < 4; ++y) {
+ for (x = 0; x < 4; ++x) {
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ VP8SetResidualCoeffs(rd->y_ac_levels[x + y * 4], &res);
+ it->top_nz_[x] = it->left_nz_[y] = PutCoeffs(bw, ctx, &res);
+ }
+ }
+ pos2 = VP8BitWriterPos(bw);
+
+ // U/V
+ VP8InitResidual(0, 2, enc, &res);
+ for (ch = 0; ch <= 2; ch += 2) {
+ for (y = 0; y < 2; ++y) {
+ for (x = 0; x < 2; ++x) {
+ const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
+ VP8SetResidualCoeffs(rd->uv_levels[ch * 2 + x + y * 2], &res);
+ it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] =
+ PutCoeffs(bw, ctx, &res);
+ }
+ }
+ }
+ pos3 = VP8BitWriterPos(bw);
+ it->luma_bits_ = pos2 - pos1;
+ it->uv_bits_ = pos3 - pos2;
+ it->bit_count_[segment][i16] += it->luma_bits_;
+ it->bit_count_[segment][2] += it->uv_bits_;
+ VP8IteratorBytesToNz(it);
+}
+
+// Same as CodeResiduals, but doesn't actually write anything.
+// Instead, it just records the event distribution.
+static void RecordResiduals(VP8EncIterator* const it,
+ const VP8ModeScore* const rd) {
+ int x, y, ch;
+ VP8Residual res;
+ VP8Encoder* const enc = it->enc_;
+
+ VP8IteratorNzToBytes(it);
+
+ if (it->mb_->type_ == 1) { // i16x16
+ VP8InitResidual(0, 1, enc, &res);
+ VP8SetResidualCoeffs(rd->y_dc_levels, &res);
+ it->top_nz_[8] = it->left_nz_[8] =
+ VP8RecordCoeffs(it->top_nz_[8] + it->left_nz_[8], &res);
+ VP8InitResidual(1, 0, enc, &res);
+ } else {
+ VP8InitResidual(0, 3, enc, &res);
+ }
+
+ // luma-AC
+ for (y = 0; y < 4; ++y) {
+ for (x = 0; x < 4; ++x) {
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ VP8SetResidualCoeffs(rd->y_ac_levels[x + y * 4], &res);
+ it->top_nz_[x] = it->left_nz_[y] = VP8RecordCoeffs(ctx, &res);
+ }
+ }
+
+ // U/V
+ VP8InitResidual(0, 2, enc, &res);
+ for (ch = 0; ch <= 2; ch += 2) {
+ for (y = 0; y < 2; ++y) {
+ for (x = 0; x < 2; ++x) {
+ const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
+ VP8SetResidualCoeffs(rd->uv_levels[ch * 2 + x + y * 2], &res);
+ it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] =
+ VP8RecordCoeffs(ctx, &res);
+ }
+ }
+ }
+
+ VP8IteratorBytesToNz(it);
+}
+
+//------------------------------------------------------------------------------
+// Token buffer
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+static int RecordTokens(VP8EncIterator* const it, const VP8ModeScore* const rd,
+ VP8TBuffer* const tokens) {
+ int x, y, ch;
+ VP8Residual res;
+ VP8Encoder* const enc = it->enc_;
+
+ VP8IteratorNzToBytes(it);
+ if (it->mb_->type_ == 1) { // i16x16
+ const int ctx = it->top_nz_[8] + it->left_nz_[8];
+ VP8InitResidual(0, 1, enc, &res);
+ VP8SetResidualCoeffs(rd->y_dc_levels, &res);
+ it->top_nz_[8] = it->left_nz_[8] =
+ VP8RecordCoeffTokens(ctx, &res, tokens);
+ VP8InitResidual(1, 0, enc, &res);
+ } else {
+ VP8InitResidual(0, 3, enc, &res);
+ }
+
+ // luma-AC
+ for (y = 0; y < 4; ++y) {
+ for (x = 0; x < 4; ++x) {
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ VP8SetResidualCoeffs(rd->y_ac_levels[x + y * 4], &res);
+ it->top_nz_[x] = it->left_nz_[y] =
+ VP8RecordCoeffTokens(ctx, &res, tokens);
+ }
+ }
+
+ // U/V
+ VP8InitResidual(0, 2, enc, &res);
+ for (ch = 0; ch <= 2; ch += 2) {
+ for (y = 0; y < 2; ++y) {
+ for (x = 0; x < 2; ++x) {
+ const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
+ VP8SetResidualCoeffs(rd->uv_levels[ch * 2 + x + y * 2], &res);
+ it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] =
+ VP8RecordCoeffTokens(ctx, &res, tokens);
+ }
+ }
+ }
+ VP8IteratorBytesToNz(it);
+ return !tokens->error_;
+}
+
+#endif // !DISABLE_TOKEN_BUFFER
+
+//------------------------------------------------------------------------------
+// ExtraInfo map / Debug function
+
+#if !defined(WEBP_DISABLE_STATS)
+
+#if SEGMENT_VISU
+static void SetBlock(uint8_t* p, int value, int size) {
+ int y;
+ for (y = 0; y < size; ++y) {
+ memset(p, value, size);
+ p += BPS;
+ }
+}
+#endif
+
+static void ResetSSE(VP8Encoder* const enc) {
+ enc->sse_[0] = 0;
+ enc->sse_[1] = 0;
+ enc->sse_[2] = 0;
+ // Note: enc->sse_[3] is managed by alpha.c
+ enc->sse_count_ = 0;
+}
+
+static void StoreSSE(const VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ const uint8_t* const in = it->yuv_in_;
+ const uint8_t* const out = it->yuv_out_;
+ // Note: not totally accurate at boundary. And doesn't include in-loop filter.
+ enc->sse_[0] += VP8SSE16x16(in + Y_OFF_ENC, out + Y_OFF_ENC);
+ enc->sse_[1] += VP8SSE8x8(in + U_OFF_ENC, out + U_OFF_ENC);
+ enc->sse_[2] += VP8SSE8x8(in + V_OFF_ENC, out + V_OFF_ENC);
+ enc->sse_count_ += 16 * 16;
+}
+
+static void StoreSideInfo(const VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ const VP8MBInfo* const mb = it->mb_;
+ WebPPicture* const pic = enc->pic_;
+
+ if (pic->stats != NULL) {
+ StoreSSE(it);
+ enc->block_count_[0] += (mb->type_ == 0);
+ enc->block_count_[1] += (mb->type_ == 1);
+ enc->block_count_[2] += (mb->skip_ != 0);
+ }
+
+ if (pic->extra_info != NULL) {
+ uint8_t* const info = &pic->extra_info[it->x_ + it->y_ * enc->mb_w_];
+ switch (pic->extra_info_type) {
+ case 1: *info = mb->type_; break;
+ case 2: *info = mb->segment_; break;
+ case 3: *info = enc->dqm_[mb->segment_].quant_; break;
+ case 4: *info = (mb->type_ == 1) ? it->preds_[0] : 0xff; break;
+ case 5: *info = mb->uv_mode_; break;
+ case 6: {
+ const int b = (int)((it->luma_bits_ + it->uv_bits_ + 7) >> 3);
+ *info = (b > 255) ? 255 : b; break;
+ }
+ case 7: *info = mb->alpha_; break;
+ default: *info = 0; break;
+ }
+ }
+#if SEGMENT_VISU // visualize segments and prediction modes
+ SetBlock(it->yuv_out_ + Y_OFF_ENC, mb->segment_ * 64, 16);
+ SetBlock(it->yuv_out_ + U_OFF_ENC, it->preds_[0] * 64, 8);
+ SetBlock(it->yuv_out_ + V_OFF_ENC, mb->uv_mode_ * 64, 8);
+#endif
+}
+
+static void ResetSideInfo(const VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ WebPPicture* const pic = enc->pic_;
+ if (pic->stats != NULL) {
+ memset(enc->block_count_, 0, sizeof(enc->block_count_));
+ }
+ ResetSSE(enc);
+}
+#else // defined(WEBP_DISABLE_STATS)
+static void ResetSSE(VP8Encoder* const enc) {
+ (void)enc;
+}
+static void StoreSideInfo(const VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ WebPPicture* const pic = enc->pic_;
+ if (pic->extra_info != NULL) {
+ if (it->x_ == 0 && it->y_ == 0) { // only do it once, at start
+ memset(pic->extra_info, 0,
+ enc->mb_w_ * enc->mb_h_ * sizeof(*pic->extra_info));
+ }
+ }
+}
+
+static void ResetSideInfo(const VP8EncIterator* const it) {
+ (void)it;
+}
+#endif // !defined(WEBP_DISABLE_STATS)
+
+static double GetPSNR(uint64_t mse, uint64_t size) {
+ return (mse > 0 && size > 0) ? 10. * log10(255. * 255. * size / mse) : 99;
+}
+
+//------------------------------------------------------------------------------
+// StatLoop(): only collect statistics (number of skips, token usage, ...).
+// This is used for deciding optimal probabilities. It also modifies the
+// quantizer value if some target (size, PSNR) was specified.
+
+static void SetLoopParams(VP8Encoder* const enc, float q) {
+ // Make sure the quality parameter is inside valid bounds
+ q = Clamp(q, 0.f, 100.f);
+
+ VP8SetSegmentParams(enc, q); // setup segment quantizations and filters
+ SetSegmentProbas(enc); // compute segment probabilities
+
+ ResetStats(enc);
+ ResetSSE(enc);
+}
+
+static uint64_t OneStatPass(VP8Encoder* const enc, VP8RDLevel rd_opt,
+ int nb_mbs, int percent_delta,
+ PassStats* const s) {
+ VP8EncIterator it;
+ uint64_t size = 0;
+ uint64_t size_p0 = 0;
+ uint64_t distortion = 0;
+ const uint64_t pixel_count = nb_mbs * 384;
+
+ VP8IteratorInit(enc, &it);
+ SetLoopParams(enc, s->q);
+ do {
+ VP8ModeScore info;
+ VP8IteratorImport(&it, NULL);
+ if (VP8Decimate(&it, &info, rd_opt)) {
+ // Just record the number of skips and act like skip_proba is not used.
+ ++enc->proba_.nb_skip_;
+ }
+ RecordResiduals(&it, &info);
+ size += info.R + info.H;
+ size_p0 += info.H;
+ distortion += info.D;
+ if (percent_delta && !VP8IteratorProgress(&it, percent_delta)) {
+ return 0;
+ }
+ VP8IteratorSaveBoundary(&it);
+ } while (VP8IteratorNext(&it) && --nb_mbs > 0);
+
+ size_p0 += enc->segment_hdr_.size_;
+ if (s->do_size_search) {
+ size += FinalizeSkipProba(enc);
+ size += FinalizeTokenProbas(&enc->proba_);
+ size = ((size + size_p0 + 1024) >> 11) + HEADER_SIZE_ESTIMATE;
+ s->value = (double)size;
+ } else {
+ s->value = GetPSNR(distortion, pixel_count);
+ }
+ return size_p0;
+}
+
+static int StatLoop(VP8Encoder* const enc) {
+ const int method = enc->method_;
+ const int do_search = enc->do_search_;
+ const int fast_probe = ((method == 0 || method == 3) && !do_search);
+ int num_pass_left = enc->config_->pass;
+ const int task_percent = 20;
+ const int percent_per_pass =
+ (task_percent + num_pass_left / 2) / num_pass_left;
+ const int final_percent = enc->percent_ + task_percent;
+ const VP8RDLevel rd_opt =
+ (method >= 3 || do_search) ? RD_OPT_BASIC : RD_OPT_NONE;
+ int nb_mbs = enc->mb_w_ * enc->mb_h_;
+ PassStats stats;
+
+ InitPassStats(enc, &stats);
+ ResetTokenStats(enc);
+
+ // Fast mode: quick analysis pass over few mbs. Better than nothing.
+ if (fast_probe) {
+ if (method == 3) { // we need more stats for method 3 to be reliable.
+ nb_mbs = (nb_mbs > 200) ? nb_mbs >> 1 : 100;
+ } else {
+ nb_mbs = (nb_mbs > 200) ? nb_mbs >> 2 : 50;
+ }
+ }
+
+ while (num_pass_left-- > 0) {
+ const int is_last_pass = (fabs(stats.dq) <= DQ_LIMIT) ||
+ (num_pass_left == 0) ||
+ (enc->max_i4_header_bits_ == 0);
+ const uint64_t size_p0 =
+ OneStatPass(enc, rd_opt, nb_mbs, percent_per_pass, &stats);
+ if (size_p0 == 0) return 0;
+#if (DEBUG_SEARCH > 0)
+ printf("#%d value:%.1lf -> %.1lf q:%.2f -> %.2f\n",
+ num_pass_left, stats.last_value, stats.value, stats.last_q, stats.q);
+#endif
+ if (enc->max_i4_header_bits_ > 0 && size_p0 > PARTITION0_SIZE_LIMIT) {
+ ++num_pass_left;
+ enc->max_i4_header_bits_ >>= 1; // strengthen header bit limitation...
+ continue; // ...and start over
+ }
+ if (is_last_pass) {
+ break;
+ }
+ // If no target size: just do several pass without changing 'q'
+ if (do_search) {
+ ComputeNextQ(&stats);
+ if (fabs(stats.dq) <= DQ_LIMIT) break;
+ }
+ }
+ if (!do_search || !stats.do_size_search) {
+ // Need to finalize probas now, since it wasn't done during the search.
+ FinalizeSkipProba(enc);
+ FinalizeTokenProbas(&enc->proba_);
+ }
+ VP8CalculateLevelCosts(&enc->proba_); // finalize costs
+ return WebPReportProgress(enc->pic_, final_percent, &enc->percent_);
+}
+
+//------------------------------------------------------------------------------
+// Main loops
+//
+
+static const uint8_t kAverageBytesPerMB[8] = { 50, 24, 16, 9, 7, 5, 3, 2 };
+
+static int PreLoopInitialize(VP8Encoder* const enc) {
+ int p;
+ int ok = 1;
+ const int average_bytes_per_MB = kAverageBytesPerMB[enc->base_quant_ >> 4];
+ const int bytes_per_parts =
+ enc->mb_w_ * enc->mb_h_ * average_bytes_per_MB / enc->num_parts_;
+ // Initialize the bit-writers
+ for (p = 0; ok && p < enc->num_parts_; ++p) {
+ ok = VP8BitWriterInit(enc->parts_ + p, bytes_per_parts);
+ }
+ if (!ok) {
+ VP8EncFreeBitWriters(enc); // malloc error occurred
+ WebPEncodingSetError(enc->pic_, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ return ok;
+}
+
+static int PostLoopFinalize(VP8EncIterator* const it, int ok) {
+ VP8Encoder* const enc = it->enc_;
+ if (ok) { // Finalize the partitions, check for extra errors.
+ int p;
+ for (p = 0; p < enc->num_parts_; ++p) {
+ VP8BitWriterFinish(enc->parts_ + p);
+ ok &= !enc->parts_[p].error_;
+ }
+ }
+
+ if (ok) { // All good. Finish up.
+#if !defined(WEBP_DISABLE_STATS)
+ if (enc->pic_->stats != NULL) { // finalize byte counters...
+ int i, s;
+ for (i = 0; i <= 2; ++i) {
+ for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
+ enc->residual_bytes_[i][s] = (int)((it->bit_count_[s][i] + 7) >> 3);
+ }
+ }
+ }
+#endif
+ VP8AdjustFilterStrength(it); // ...and store filter stats.
+ } else {
+ // Something bad happened -> need to do some memory cleanup.
+ VP8EncFreeBitWriters(enc);
+ }
+ return ok;
+}
+
+//------------------------------------------------------------------------------
+// VP8EncLoop(): does the final bitstream coding.
+
+static void ResetAfterSkip(VP8EncIterator* const it) {
+ if (it->mb_->type_ == 1) {
+ *it->nz_ = 0; // reset all predictors
+ it->left_nz_[8] = 0;
+ } else {
+ *it->nz_ &= (1 << 24); // preserve the dc_nz bit
+ }
+}
+
+int VP8EncLoop(VP8Encoder* const enc) {
+ VP8EncIterator it;
+ int ok = PreLoopInitialize(enc);
+ if (!ok) return 0;
+
+ StatLoop(enc); // stats-collection loop
+
+ VP8IteratorInit(enc, &it);
+ VP8InitFilter(&it);
+ do {
+ VP8ModeScore info;
+ const int dont_use_skip = !enc->proba_.use_skip_proba_;
+ const VP8RDLevel rd_opt = enc->rd_opt_level_;
+
+ VP8IteratorImport(&it, NULL);
+ // Warning! order is important: first call VP8Decimate() and
+ // *then* decide how to code the skip decision if there's one.
+ if (!VP8Decimate(&it, &info, rd_opt) || dont_use_skip) {
+ CodeResiduals(it.bw_, &it, &info);
+ } else { // reset predictors after a skip
+ ResetAfterSkip(&it);
+ }
+ StoreSideInfo(&it);
+ VP8StoreFilterStats(&it);
+ VP8IteratorExport(&it);
+ ok = VP8IteratorProgress(&it, 20);
+ VP8IteratorSaveBoundary(&it);
+ } while (ok && VP8IteratorNext(&it));
+
+ return PostLoopFinalize(&it, ok);
+}
+
+//------------------------------------------------------------------------------
+// Single pass using Token Buffer.
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+#define MIN_COUNT 96 // minimum number of macroblocks before updating stats
+
+int VP8EncTokenLoop(VP8Encoder* const enc) {
+ // Roughly refresh the proba eight times per pass
+ int max_count = (enc->mb_w_ * enc->mb_h_) >> 3;
+ int num_pass_left = enc->config_->pass;
+ int remaining_progress = 40; // percents
+ const int do_search = enc->do_search_;
+ VP8EncIterator it;
+ VP8EncProba* const proba = &enc->proba_;
+ const VP8RDLevel rd_opt = enc->rd_opt_level_;
+ const uint64_t pixel_count = enc->mb_w_ * enc->mb_h_ * 384;
+ PassStats stats;
+ int ok;
+
+ InitPassStats(enc, &stats);
+ ok = PreLoopInitialize(enc);
+ if (!ok) return 0;
+
+ if (max_count < MIN_COUNT) max_count = MIN_COUNT;
+
+ assert(enc->num_parts_ == 1);
+ assert(enc->use_tokens_);
+ assert(proba->use_skip_proba_ == 0);
+ assert(rd_opt >= RD_OPT_BASIC); // otherwise, token-buffer won't be useful
+ assert(num_pass_left > 0);
+
+ while (ok && num_pass_left-- > 0) {
+ const int is_last_pass = (fabs(stats.dq) <= DQ_LIMIT) ||
+ (num_pass_left == 0) ||
+ (enc->max_i4_header_bits_ == 0);
+ uint64_t size_p0 = 0;
+ uint64_t distortion = 0;
+ int cnt = max_count;
+ // The final number of passes is not trivial to know in advance.
+ const int pass_progress = remaining_progress / (2 + num_pass_left);
+ remaining_progress -= pass_progress;
+ VP8IteratorInit(enc, &it);
+ SetLoopParams(enc, stats.q);
+ if (is_last_pass) {
+ ResetTokenStats(enc);
+ VP8InitFilter(&it); // don't collect stats until last pass (too costly)
+ }
+ VP8TBufferClear(&enc->tokens_);
+ do {
+ VP8ModeScore info;
+ VP8IteratorImport(&it, NULL);
+ if (--cnt < 0) {
+ FinalizeTokenProbas(proba);
+ VP8CalculateLevelCosts(proba); // refresh cost tables for rd-opt
+ cnt = max_count;
+ }
+ VP8Decimate(&it, &info, rd_opt);
+ ok = RecordTokens(&it, &info, &enc->tokens_);
+ if (!ok) {
+ WebPEncodingSetError(enc->pic_, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ break;
+ }
+ size_p0 += info.H;
+ distortion += info.D;
+ if (is_last_pass) {
+ StoreSideInfo(&it);
+ VP8StoreFilterStats(&it);
+ VP8IteratorExport(&it);
+ ok = VP8IteratorProgress(&it, pass_progress);
+ }
+ VP8IteratorSaveBoundary(&it);
+ } while (ok && VP8IteratorNext(&it));
+ if (!ok) break;
+
+ size_p0 += enc->segment_hdr_.size_;
+ if (stats.do_size_search) {
+ uint64_t size = FinalizeTokenProbas(&enc->proba_);
+ size += VP8EstimateTokenSize(&enc->tokens_,
+ (const uint8_t*)proba->coeffs_);
+ size = (size + size_p0 + 1024) >> 11; // -> size in bytes
+ size += HEADER_SIZE_ESTIMATE;
+ stats.value = (double)size;
+ } else { // compute and store PSNR
+ stats.value = GetPSNR(distortion, pixel_count);
+ }
+
+#if (DEBUG_SEARCH > 0)
+ printf("#%2d metric:%.1lf -> %.1lf last_q=%.2lf q=%.2lf dq=%.2lf "
+ " range:[%.1f, %.1f]\n",
+ num_pass_left, stats.last_value, stats.value,
+ stats.last_q, stats.q, stats.dq, stats.qmin, stats.qmax);
+#endif
+ if (enc->max_i4_header_bits_ > 0 && size_p0 > PARTITION0_SIZE_LIMIT) {
+ ++num_pass_left;
+ enc->max_i4_header_bits_ >>= 1; // strengthen header bit limitation...
+ if (is_last_pass) {
+ ResetSideInfo(&it);
+ }
+ continue; // ...and start over
+ }
+ if (is_last_pass) {
+ break; // done
+ }
+ if (do_search) {
+ ComputeNextQ(&stats); // Adjust q
+ }
+ }
+ if (ok) {
+ if (!stats.do_size_search) {
+ FinalizeTokenProbas(&enc->proba_);
+ }
+ ok = VP8EmitTokens(&enc->tokens_, enc->parts_ + 0,
+ (const uint8_t*)proba->coeffs_, 1);
+ }
+ ok = ok && WebPReportProgress(enc->pic_, enc->percent_ + remaining_progress,
+ &enc->percent_);
+ return PostLoopFinalize(&it, ok);
+}
+
+#else
+
+int VP8EncTokenLoop(VP8Encoder* const enc) {
+ (void)enc;
+ return 0; // we shouldn't be here.
+}
+
+#endif // DISABLE_TOKEN_BUFFER
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/histogram_enc.c b/media/libwebp/src/enc/histogram_enc.c
new file mode 100644
index 0000000000..8418def2e1
--- /dev/null
+++ b/media/libwebp/src/enc/histogram_enc.c
@@ -0,0 +1,1248 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+//
+#ifdef HAVE_CONFIG_H
+#include "src/webp/config.h"
+#endif
+
+#include <float.h>
+#include <math.h>
+
+#include "src/dsp/lossless.h"
+#include "src/dsp/lossless_common.h"
+#include "src/enc/backward_references_enc.h"
+#include "src/enc/histogram_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/utils/utils.h"
+
+#define MAX_BIT_COST FLT_MAX
+
+// Number of partitions for the three dominant (literal, red and blue) symbol
+// costs.
+#define NUM_PARTITIONS 4
+// The size of the bin-hash corresponding to the three dominant costs.
+#define BIN_SIZE (NUM_PARTITIONS * NUM_PARTITIONS * NUM_PARTITIONS)
+// Maximum number of histograms allowed in greedy combining algorithm.
+#define MAX_HISTO_GREEDY 100
+
+static void HistogramClear(VP8LHistogram* const p) {
+ uint32_t* const literal = p->literal_;
+ const int cache_bits = p->palette_code_bits_;
+ const int histo_size = VP8LGetHistogramSize(cache_bits);
+ memset(p, 0, histo_size);
+ p->palette_code_bits_ = cache_bits;
+ p->literal_ = literal;
+}
+
+// Swap two histogram pointers.
+static void HistogramSwap(VP8LHistogram** const A, VP8LHistogram** const B) {
+ VP8LHistogram* const tmp = *A;
+ *A = *B;
+ *B = tmp;
+}
+
+static void HistogramCopy(const VP8LHistogram* const src,
+ VP8LHistogram* const dst) {
+ uint32_t* const dst_literal = dst->literal_;
+ const int dst_cache_bits = dst->palette_code_bits_;
+ const int literal_size = VP8LHistogramNumCodes(dst_cache_bits);
+ const int histo_size = VP8LGetHistogramSize(dst_cache_bits);
+ assert(src->palette_code_bits_ == dst_cache_bits);
+ memcpy(dst, src, histo_size);
+ dst->literal_ = dst_literal;
+ memcpy(dst->literal_, src->literal_, literal_size * sizeof(*dst->literal_));
+}
+
+int VP8LGetHistogramSize(int cache_bits) {
+ const int literal_size = VP8LHistogramNumCodes(cache_bits);
+ const size_t total_size = sizeof(VP8LHistogram) + sizeof(int) * literal_size;
+ assert(total_size <= (size_t)0x7fffffff);
+ return (int)total_size;
+}
+
+void VP8LFreeHistogram(VP8LHistogram* const histo) {
+ WebPSafeFree(histo);
+}
+
+void VP8LFreeHistogramSet(VP8LHistogramSet* const histo) {
+ WebPSafeFree(histo);
+}
+
+void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
+ VP8LHistogram* const histo) {
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ while (VP8LRefsCursorOk(&c)) {
+ VP8LHistogramAddSinglePixOrCopy(histo, c.cur_pos, NULL, 0);
+ VP8LRefsCursorNext(&c);
+ }
+}
+
+void VP8LHistogramCreate(VP8LHistogram* const p,
+ const VP8LBackwardRefs* const refs,
+ int palette_code_bits) {
+ if (palette_code_bits >= 0) {
+ p->palette_code_bits_ = palette_code_bits;
+ }
+ HistogramClear(p);
+ VP8LHistogramStoreRefs(refs, p);
+}
+
+void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits,
+ int init_arrays) {
+ p->palette_code_bits_ = palette_code_bits;
+ if (init_arrays) {
+ HistogramClear(p);
+ } else {
+ p->trivial_symbol_ = 0;
+ p->bit_cost_ = 0.;
+ p->literal_cost_ = 0.;
+ p->red_cost_ = 0.;
+ p->blue_cost_ = 0.;
+ memset(p->is_used_, 0, sizeof(p->is_used_));
+ }
+}
+
+VP8LHistogram* VP8LAllocateHistogram(int cache_bits) {
+ VP8LHistogram* histo = NULL;
+ const int total_size = VP8LGetHistogramSize(cache_bits);
+ uint8_t* const memory = (uint8_t*)WebPSafeMalloc(total_size, sizeof(*memory));
+ if (memory == NULL) return NULL;
+ histo = (VP8LHistogram*)memory;
+ // literal_ won't necessary be aligned.
+ histo->literal_ = (uint32_t*)(memory + sizeof(VP8LHistogram));
+ VP8LHistogramInit(histo, cache_bits, /*init_arrays=*/ 0);
+ return histo;
+}
+
+// Resets the pointers of the histograms to point to the bit buffer in the set.
+static void HistogramSetResetPointers(VP8LHistogramSet* const set,
+ int cache_bits) {
+ int i;
+ const int histo_size = VP8LGetHistogramSize(cache_bits);
+ uint8_t* memory = (uint8_t*) (set->histograms);
+ memory += set->max_size * sizeof(*set->histograms);
+ for (i = 0; i < set->max_size; ++i) {
+ memory = (uint8_t*) WEBP_ALIGN(memory);
+ set->histograms[i] = (VP8LHistogram*) memory;
+ // literal_ won't necessary be aligned.
+ set->histograms[i]->literal_ = (uint32_t*)(memory + sizeof(VP8LHistogram));
+ memory += histo_size;
+ }
+}
+
+// Returns the total size of the VP8LHistogramSet.
+static size_t HistogramSetTotalSize(int size, int cache_bits) {
+ const int histo_size = VP8LGetHistogramSize(cache_bits);
+ return (sizeof(VP8LHistogramSet) + size * (sizeof(VP8LHistogram*) +
+ histo_size + WEBP_ALIGN_CST));
+}
+
+VP8LHistogramSet* VP8LAllocateHistogramSet(int size, int cache_bits) {
+ int i;
+ VP8LHistogramSet* set;
+ const size_t total_size = HistogramSetTotalSize(size, cache_bits);
+ uint8_t* memory = (uint8_t*)WebPSafeMalloc(total_size, sizeof(*memory));
+ if (memory == NULL) return NULL;
+
+ set = (VP8LHistogramSet*)memory;
+ memory += sizeof(*set);
+ set->histograms = (VP8LHistogram**)memory;
+ set->max_size = size;
+ set->size = size;
+ HistogramSetResetPointers(set, cache_bits);
+ for (i = 0; i < size; ++i) {
+ VP8LHistogramInit(set->histograms[i], cache_bits, /*init_arrays=*/ 0);
+ }
+ return set;
+}
+
+void VP8LHistogramSetClear(VP8LHistogramSet* const set) {
+ int i;
+ const int cache_bits = set->histograms[0]->palette_code_bits_;
+ const int size = set->max_size;
+ const size_t total_size = HistogramSetTotalSize(size, cache_bits);
+ uint8_t* memory = (uint8_t*)set;
+
+ memset(memory, 0, total_size);
+ memory += sizeof(*set);
+ set->histograms = (VP8LHistogram**)memory;
+ set->max_size = size;
+ set->size = size;
+ HistogramSetResetPointers(set, cache_bits);
+ for (i = 0; i < size; ++i) {
+ set->histograms[i]->palette_code_bits_ = cache_bits;
+ }
+}
+
+// Removes the histogram 'i' from 'set' by setting it to NULL.
+static void HistogramSetRemoveHistogram(VP8LHistogramSet* const set, int i,
+ int* const num_used) {
+ assert(set->histograms[i] != NULL);
+ set->histograms[i] = NULL;
+ --*num_used;
+ // If we remove the last valid one, shrink until the next valid one.
+ if (i == set->size - 1) {
+ while (set->size >= 1 && set->histograms[set->size - 1] == NULL) {
+ --set->size;
+ }
+ }
+}
+
+// -----------------------------------------------------------------------------
+
+void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const histo,
+ const PixOrCopy* const v,
+ int (*const distance_modifier)(int, int),
+ int distance_modifier_arg0) {
+ if (PixOrCopyIsLiteral(v)) {
+ ++histo->alpha_[PixOrCopyLiteral(v, 3)];
+ ++histo->red_[PixOrCopyLiteral(v, 2)];
+ ++histo->literal_[PixOrCopyLiteral(v, 1)];
+ ++histo->blue_[PixOrCopyLiteral(v, 0)];
+ } else if (PixOrCopyIsCacheIdx(v)) {
+ const int literal_ix =
+ NUM_LITERAL_CODES + NUM_LENGTH_CODES + PixOrCopyCacheIdx(v);
+ assert(histo->palette_code_bits_ != 0);
+ ++histo->literal_[literal_ix];
+ } else {
+ int code, extra_bits;
+ VP8LPrefixEncodeBits(PixOrCopyLength(v), &code, &extra_bits);
+ ++histo->literal_[NUM_LITERAL_CODES + code];
+ if (distance_modifier == NULL) {
+ VP8LPrefixEncodeBits(PixOrCopyDistance(v), &code, &extra_bits);
+ } else {
+ VP8LPrefixEncodeBits(
+ distance_modifier(distance_modifier_arg0, PixOrCopyDistance(v)),
+ &code, &extra_bits);
+ }
+ ++histo->distance_[code];
+ }
+}
+
+// -----------------------------------------------------------------------------
+// Entropy-related functions.
+
+static WEBP_INLINE float BitsEntropyRefine(const VP8LBitEntropy* entropy) {
+ float mix;
+ if (entropy->nonzeros < 5) {
+ if (entropy->nonzeros <= 1) {
+ return 0;
+ }
+ // Two symbols, they will be 0 and 1 in a Huffman code.
+ // Let's mix in a bit of entropy to favor good clustering when
+ // distributions of these are combined.
+ if (entropy->nonzeros == 2) {
+ return 0.99f * entropy->sum + 0.01f * entropy->entropy;
+ }
+ // No matter what the entropy says, we cannot be better than min_limit
+ // with Huffman coding. I am mixing a bit of entropy into the
+ // min_limit since it produces much better (~0.5 %) compression results
+ // perhaps because of better entropy clustering.
+ if (entropy->nonzeros == 3) {
+ mix = 0.95f;
+ } else {
+ mix = 0.7f; // nonzeros == 4.
+ }
+ } else {
+ mix = 0.627f;
+ }
+
+ {
+ float min_limit = 2.f * entropy->sum - entropy->max_val;
+ min_limit = mix * min_limit + (1.f - mix) * entropy->entropy;
+ return (entropy->entropy < min_limit) ? min_limit : entropy->entropy;
+ }
+}
+
+float VP8LBitsEntropy(const uint32_t* const array, int n) {
+ VP8LBitEntropy entropy;
+ VP8LBitsEntropyUnrefined(array, n, &entropy);
+
+ return BitsEntropyRefine(&entropy);
+}
+
+static float InitialHuffmanCost(void) {
+ // Small bias because Huffman code length is typically not stored in
+ // full length.
+ static const int kHuffmanCodeOfHuffmanCodeSize = CODE_LENGTH_CODES * 3;
+ static const float kSmallBias = 9.1f;
+ return kHuffmanCodeOfHuffmanCodeSize - kSmallBias;
+}
+
+// Finalize the Huffman cost based on streak numbers and length type (<3 or >=3)
+static float FinalHuffmanCost(const VP8LStreaks* const stats) {
+ // The constants in this function are experimental and got rounded from
+ // their original values in 1/8 when switched to 1/1024.
+ float retval = InitialHuffmanCost();
+ // Second coefficient: Many zeros in the histogram are covered efficiently
+ // by a run-length encode. Originally 2/8.
+ retval += stats->counts[0] * 1.5625f + 0.234375f * stats->streaks[0][1];
+ // Second coefficient: Constant values are encoded less efficiently, but still
+ // RLE'ed. Originally 6/8.
+ retval += stats->counts[1] * 2.578125f + 0.703125f * stats->streaks[1][1];
+ // 0s are usually encoded more efficiently than non-0s.
+ // Originally 15/8.
+ retval += 1.796875f * stats->streaks[0][0];
+ // Originally 26/8.
+ retval += 3.28125f * stats->streaks[1][0];
+ return retval;
+}
+
+// Get the symbol entropy for the distribution 'population'.
+// Set 'trivial_sym', if there's only one symbol present in the distribution.
+static float PopulationCost(const uint32_t* const population, int length,
+ uint32_t* const trivial_sym,
+ uint8_t* const is_used) {
+ VP8LBitEntropy bit_entropy;
+ VP8LStreaks stats;
+ VP8LGetEntropyUnrefined(population, length, &bit_entropy, &stats);
+ if (trivial_sym != NULL) {
+ *trivial_sym = (bit_entropy.nonzeros == 1) ? bit_entropy.nonzero_code
+ : VP8L_NON_TRIVIAL_SYM;
+ }
+ // The histogram is used if there is at least one non-zero streak.
+ *is_used = (stats.streaks[1][0] != 0 || stats.streaks[1][1] != 0);
+
+ return BitsEntropyRefine(&bit_entropy) + FinalHuffmanCost(&stats);
+}
+
+// trivial_at_end is 1 if the two histograms only have one element that is
+// non-zero: both the zero-th one, or both the last one.
+static WEBP_INLINE float GetCombinedEntropy(const uint32_t* const X,
+ const uint32_t* const Y, int length,
+ int is_X_used, int is_Y_used,
+ int trivial_at_end) {
+ VP8LStreaks stats;
+ if (trivial_at_end) {
+ // This configuration is due to palettization that transforms an indexed
+ // pixel into 0xff000000 | (pixel << 8) in VP8LBundleColorMap.
+ // BitsEntropyRefine is 0 for histograms with only one non-zero value.
+ // Only FinalHuffmanCost needs to be evaluated.
+ memset(&stats, 0, sizeof(stats));
+ // Deal with the non-zero value at index 0 or length-1.
+ stats.streaks[1][0] = 1;
+ // Deal with the following/previous zero streak.
+ stats.counts[0] = 1;
+ stats.streaks[0][1] = length - 1;
+ return FinalHuffmanCost(&stats);
+ } else {
+ VP8LBitEntropy bit_entropy;
+ if (is_X_used) {
+ if (is_Y_used) {
+ VP8LGetCombinedEntropyUnrefined(X, Y, length, &bit_entropy, &stats);
+ } else {
+ VP8LGetEntropyUnrefined(X, length, &bit_entropy, &stats);
+ }
+ } else {
+ if (is_Y_used) {
+ VP8LGetEntropyUnrefined(Y, length, &bit_entropy, &stats);
+ } else {
+ memset(&stats, 0, sizeof(stats));
+ stats.counts[0] = 1;
+ stats.streaks[0][length > 3] = length;
+ VP8LBitEntropyInit(&bit_entropy);
+ }
+ }
+
+ return BitsEntropyRefine(&bit_entropy) + FinalHuffmanCost(&stats);
+ }
+}
+
+// Estimates the Entropy + Huffman + other block overhead size cost.
+float VP8LHistogramEstimateBits(VP8LHistogram* const p) {
+ return
+ PopulationCost(p->literal_, VP8LHistogramNumCodes(p->palette_code_bits_),
+ NULL, &p->is_used_[0])
+ + PopulationCost(p->red_, NUM_LITERAL_CODES, NULL, &p->is_used_[1])
+ + PopulationCost(p->blue_, NUM_LITERAL_CODES, NULL, &p->is_used_[2])
+ + PopulationCost(p->alpha_, NUM_LITERAL_CODES, NULL, &p->is_used_[3])
+ + PopulationCost(p->distance_, NUM_DISTANCE_CODES, NULL, &p->is_used_[4])
+ + VP8LExtraCost(p->literal_ + NUM_LITERAL_CODES, NUM_LENGTH_CODES)
+ + VP8LExtraCost(p->distance_, NUM_DISTANCE_CODES);
+}
+
+// -----------------------------------------------------------------------------
+// Various histogram combine/cost-eval functions
+
+static int GetCombinedHistogramEntropy(const VP8LHistogram* const a,
+ const VP8LHistogram* const b,
+ float cost_threshold, float* cost) {
+ const int palette_code_bits = a->palette_code_bits_;
+ int trivial_at_end = 0;
+ assert(a->palette_code_bits_ == b->palette_code_bits_);
+ *cost += GetCombinedEntropy(a->literal_, b->literal_,
+ VP8LHistogramNumCodes(palette_code_bits),
+ a->is_used_[0], b->is_used_[0], 0);
+ *cost += VP8LExtraCostCombined(a->literal_ + NUM_LITERAL_CODES,
+ b->literal_ + NUM_LITERAL_CODES,
+ NUM_LENGTH_CODES);
+ if (*cost > cost_threshold) return 0;
+
+ if (a->trivial_symbol_ != VP8L_NON_TRIVIAL_SYM &&
+ a->trivial_symbol_ == b->trivial_symbol_) {
+ // A, R and B are all 0 or 0xff.
+ const uint32_t color_a = (a->trivial_symbol_ >> 24) & 0xff;
+ const uint32_t color_r = (a->trivial_symbol_ >> 16) & 0xff;
+ const uint32_t color_b = (a->trivial_symbol_ >> 0) & 0xff;
+ if ((color_a == 0 || color_a == 0xff) &&
+ (color_r == 0 || color_r == 0xff) &&
+ (color_b == 0 || color_b == 0xff)) {
+ trivial_at_end = 1;
+ }
+ }
+
+ *cost +=
+ GetCombinedEntropy(a->red_, b->red_, NUM_LITERAL_CODES, a->is_used_[1],
+ b->is_used_[1], trivial_at_end);
+ if (*cost > cost_threshold) return 0;
+
+ *cost +=
+ GetCombinedEntropy(a->blue_, b->blue_, NUM_LITERAL_CODES, a->is_used_[2],
+ b->is_used_[2], trivial_at_end);
+ if (*cost > cost_threshold) return 0;
+
+ *cost +=
+ GetCombinedEntropy(a->alpha_, b->alpha_, NUM_LITERAL_CODES,
+ a->is_used_[3], b->is_used_[3], trivial_at_end);
+ if (*cost > cost_threshold) return 0;
+
+ *cost +=
+ GetCombinedEntropy(a->distance_, b->distance_, NUM_DISTANCE_CODES,
+ a->is_used_[4], b->is_used_[4], 0);
+ *cost +=
+ VP8LExtraCostCombined(a->distance_, b->distance_, NUM_DISTANCE_CODES);
+ if (*cost > cost_threshold) return 0;
+
+ return 1;
+}
+
+static WEBP_INLINE void HistogramAdd(const VP8LHistogram* const a,
+ const VP8LHistogram* const b,
+ VP8LHistogram* const out) {
+ VP8LHistogramAdd(a, b, out);
+ out->trivial_symbol_ = (a->trivial_symbol_ == b->trivial_symbol_)
+ ? a->trivial_symbol_
+ : VP8L_NON_TRIVIAL_SYM;
+}
+
+// Performs out = a + b, computing the cost C(a+b) - C(a) - C(b) while comparing
+// to the threshold value 'cost_threshold'. The score returned is
+// Score = C(a+b) - C(a) - C(b), where C(a) + C(b) is known and fixed.
+// Since the previous score passed is 'cost_threshold', we only need to compare
+// the partial cost against 'cost_threshold + C(a) + C(b)' to possibly bail-out
+// early.
+static float HistogramAddEval(const VP8LHistogram* const a,
+ const VP8LHistogram* const b,
+ VP8LHistogram* const out, float cost_threshold) {
+ float cost = 0;
+ const float sum_cost = a->bit_cost_ + b->bit_cost_;
+ cost_threshold += sum_cost;
+
+ if (GetCombinedHistogramEntropy(a, b, cost_threshold, &cost)) {
+ HistogramAdd(a, b, out);
+ out->bit_cost_ = cost;
+ out->palette_code_bits_ = a->palette_code_bits_;
+ }
+
+ return cost - sum_cost;
+}
+
+// Same as HistogramAddEval(), except that the resulting histogram
+// is not stored. Only the cost C(a+b) - C(a) is evaluated. We omit
+// the term C(b) which is constant over all the evaluations.
+static float HistogramAddThresh(const VP8LHistogram* const a,
+ const VP8LHistogram* const b,
+ float cost_threshold) {
+ float cost;
+ assert(a != NULL && b != NULL);
+ cost = -a->bit_cost_;
+ GetCombinedHistogramEntropy(a, b, cost_threshold, &cost);
+ return cost;
+}
+
+// -----------------------------------------------------------------------------
+
+// The structure to keep track of cost range for the three dominant entropy
+// symbols.
+typedef struct {
+ float literal_max_;
+ float literal_min_;
+ float red_max_;
+ float red_min_;
+ float blue_max_;
+ float blue_min_;
+} DominantCostRange;
+
+static void DominantCostRangeInit(DominantCostRange* const c) {
+ c->literal_max_ = 0.;
+ c->literal_min_ = MAX_BIT_COST;
+ c->red_max_ = 0.;
+ c->red_min_ = MAX_BIT_COST;
+ c->blue_max_ = 0.;
+ c->blue_min_ = MAX_BIT_COST;
+}
+
+static void UpdateDominantCostRange(
+ const VP8LHistogram* const h, DominantCostRange* const c) {
+ if (c->literal_max_ < h->literal_cost_) c->literal_max_ = h->literal_cost_;
+ if (c->literal_min_ > h->literal_cost_) c->literal_min_ = h->literal_cost_;
+ if (c->red_max_ < h->red_cost_) c->red_max_ = h->red_cost_;
+ if (c->red_min_ > h->red_cost_) c->red_min_ = h->red_cost_;
+ if (c->blue_max_ < h->blue_cost_) c->blue_max_ = h->blue_cost_;
+ if (c->blue_min_ > h->blue_cost_) c->blue_min_ = h->blue_cost_;
+}
+
+static void UpdateHistogramCost(VP8LHistogram* const h) {
+ uint32_t alpha_sym, red_sym, blue_sym;
+ const float alpha_cost =
+ PopulationCost(h->alpha_, NUM_LITERAL_CODES, &alpha_sym, &h->is_used_[3]);
+ const float distance_cost =
+ PopulationCost(h->distance_, NUM_DISTANCE_CODES, NULL, &h->is_used_[4]) +
+ VP8LExtraCost(h->distance_, NUM_DISTANCE_CODES);
+ const int num_codes = VP8LHistogramNumCodes(h->palette_code_bits_);
+ h->literal_cost_ =
+ PopulationCost(h->literal_, num_codes, NULL, &h->is_used_[0]) +
+ VP8LExtraCost(h->literal_ + NUM_LITERAL_CODES, NUM_LENGTH_CODES);
+ h->red_cost_ =
+ PopulationCost(h->red_, NUM_LITERAL_CODES, &red_sym, &h->is_used_[1]);
+ h->blue_cost_ =
+ PopulationCost(h->blue_, NUM_LITERAL_CODES, &blue_sym, &h->is_used_[2]);
+ h->bit_cost_ = h->literal_cost_ + h->red_cost_ + h->blue_cost_ +
+ alpha_cost + distance_cost;
+ if ((alpha_sym | red_sym | blue_sym) == VP8L_NON_TRIVIAL_SYM) {
+ h->trivial_symbol_ = VP8L_NON_TRIVIAL_SYM;
+ } else {
+ h->trivial_symbol_ =
+ ((uint32_t)alpha_sym << 24) | (red_sym << 16) | (blue_sym << 0);
+ }
+}
+
+static int GetBinIdForEntropy(float min, float max, float val) {
+ const float range = max - min;
+ if (range > 0.) {
+ const float delta = val - min;
+ return (int)((NUM_PARTITIONS - 1e-6) * delta / range);
+ } else {
+ return 0;
+ }
+}
+
+static int GetHistoBinIndex(const VP8LHistogram* const h,
+ const DominantCostRange* const c, int low_effort) {
+ int bin_id = GetBinIdForEntropy(c->literal_min_, c->literal_max_,
+ h->literal_cost_);
+ assert(bin_id < NUM_PARTITIONS);
+ if (!low_effort) {
+ bin_id = bin_id * NUM_PARTITIONS
+ + GetBinIdForEntropy(c->red_min_, c->red_max_, h->red_cost_);
+ bin_id = bin_id * NUM_PARTITIONS
+ + GetBinIdForEntropy(c->blue_min_, c->blue_max_, h->blue_cost_);
+ assert(bin_id < BIN_SIZE);
+ }
+ return bin_id;
+}
+
+// Construct the histograms from backward references.
+static void HistogramBuild(
+ int xsize, int histo_bits, const VP8LBackwardRefs* const backward_refs,
+ VP8LHistogramSet* const image_histo) {
+ int x = 0, y = 0;
+ const int histo_xsize = VP8LSubSampleSize(xsize, histo_bits);
+ VP8LHistogram** const histograms = image_histo->histograms;
+ VP8LRefsCursor c = VP8LRefsCursorInit(backward_refs);
+ assert(histo_bits > 0);
+ VP8LHistogramSetClear(image_histo);
+ while (VP8LRefsCursorOk(&c)) {
+ const PixOrCopy* const v = c.cur_pos;
+ const int ix = (y >> histo_bits) * histo_xsize + (x >> histo_bits);
+ VP8LHistogramAddSinglePixOrCopy(histograms[ix], v, NULL, 0);
+ x += PixOrCopyLength(v);
+ while (x >= xsize) {
+ x -= xsize;
+ ++y;
+ }
+ VP8LRefsCursorNext(&c);
+ }
+}
+
+// Copies the histograms and computes its bit_cost.
+static const uint16_t kInvalidHistogramSymbol = (uint16_t)(-1);
+static void HistogramCopyAndAnalyze(VP8LHistogramSet* const orig_histo,
+ VP8LHistogramSet* const image_histo,
+ int* const num_used,
+ uint16_t* const histogram_symbols) {
+ int i, cluster_id;
+ int num_used_orig = *num_used;
+ VP8LHistogram** const orig_histograms = orig_histo->histograms;
+ VP8LHistogram** const histograms = image_histo->histograms;
+ assert(image_histo->max_size == orig_histo->max_size);
+ for (cluster_id = 0, i = 0; i < orig_histo->max_size; ++i) {
+ VP8LHistogram* const histo = orig_histograms[i];
+ UpdateHistogramCost(histo);
+
+ // Skip the histogram if it is completely empty, which can happen for tiles
+ // with no information (when they are skipped because of LZ77).
+ if (!histo->is_used_[0] && !histo->is_used_[1] && !histo->is_used_[2]
+ && !histo->is_used_[3] && !histo->is_used_[4]) {
+ // The first histogram is always used. If an histogram is empty, we set
+ // its id to be the same as the previous one: this will improve
+ // compressibility for later LZ77.
+ assert(i > 0);
+ HistogramSetRemoveHistogram(image_histo, i, num_used);
+ HistogramSetRemoveHistogram(orig_histo, i, &num_used_orig);
+ histogram_symbols[i] = kInvalidHistogramSymbol;
+ } else {
+ // Copy histograms from orig_histo[] to image_histo[].
+ HistogramCopy(histo, histograms[i]);
+ histogram_symbols[i] = cluster_id++;
+ assert(cluster_id <= image_histo->max_size);
+ }
+ }
+}
+
+// Partition histograms to different entropy bins for three dominant (literal,
+// red and blue) symbol costs and compute the histogram aggregate bit_cost.
+static void HistogramAnalyzeEntropyBin(VP8LHistogramSet* const image_histo,
+ uint16_t* const bin_map,
+ int low_effort) {
+ int i;
+ VP8LHistogram** const histograms = image_histo->histograms;
+ const int histo_size = image_histo->size;
+ DominantCostRange cost_range;
+ DominantCostRangeInit(&cost_range);
+
+ // Analyze the dominant (literal, red and blue) entropy costs.
+ for (i = 0; i < histo_size; ++i) {
+ if (histograms[i] == NULL) continue;
+ UpdateDominantCostRange(histograms[i], &cost_range);
+ }
+
+ // bin-hash histograms on three of the dominant (literal, red and blue)
+ // symbol costs and store the resulting bin_id for each histogram.
+ for (i = 0; i < histo_size; ++i) {
+ // bin_map[i] is not set to a special value as its use will later be guarded
+ // by another (histograms[i] == NULL).
+ if (histograms[i] == NULL) continue;
+ bin_map[i] = GetHistoBinIndex(histograms[i], &cost_range, low_effort);
+ }
+}
+
+// Merges some histograms with same bin_id together if it's advantageous.
+// Sets the remaining histograms to NULL.
+static void HistogramCombineEntropyBin(
+ VP8LHistogramSet* const image_histo, int* num_used,
+ const uint16_t* const clusters, uint16_t* const cluster_mappings,
+ VP8LHistogram* cur_combo, const uint16_t* const bin_map, int num_bins,
+ float combine_cost_factor, int low_effort) {
+ VP8LHistogram** const histograms = image_histo->histograms;
+ int idx;
+ struct {
+ int16_t first; // position of the histogram that accumulates all
+ // histograms with the same bin_id
+ uint16_t num_combine_failures; // number of combine failures per bin_id
+ } bin_info[BIN_SIZE];
+
+ assert(num_bins <= BIN_SIZE);
+ for (idx = 0; idx < num_bins; ++idx) {
+ bin_info[idx].first = -1;
+ bin_info[idx].num_combine_failures = 0;
+ }
+
+ // By default, a cluster matches itself.
+ for (idx = 0; idx < *num_used; ++idx) cluster_mappings[idx] = idx;
+ for (idx = 0; idx < image_histo->size; ++idx) {
+ int bin_id, first;
+ if (histograms[idx] == NULL) continue;
+ bin_id = bin_map[idx];
+ first = bin_info[bin_id].first;
+ if (first == -1) {
+ bin_info[bin_id].first = idx;
+ } else if (low_effort) {
+ HistogramAdd(histograms[idx], histograms[first], histograms[first]);
+ HistogramSetRemoveHistogram(image_histo, idx, num_used);
+ cluster_mappings[clusters[idx]] = clusters[first];
+ } else {
+ // try to merge #idx into #first (both share the same bin_id)
+ const float bit_cost = histograms[idx]->bit_cost_;
+ const float bit_cost_thresh = -bit_cost * combine_cost_factor;
+ const float curr_cost_diff = HistogramAddEval(
+ histograms[first], histograms[idx], cur_combo, bit_cost_thresh);
+ if (curr_cost_diff < bit_cost_thresh) {
+ // Try to merge two histograms only if the combo is a trivial one or
+ // the two candidate histograms are already non-trivial.
+ // For some images, 'try_combine' turns out to be false for a lot of
+ // histogram pairs. In that case, we fallback to combining
+ // histograms as usual to avoid increasing the header size.
+ const int try_combine =
+ (cur_combo->trivial_symbol_ != VP8L_NON_TRIVIAL_SYM) ||
+ ((histograms[idx]->trivial_symbol_ == VP8L_NON_TRIVIAL_SYM) &&
+ (histograms[first]->trivial_symbol_ == VP8L_NON_TRIVIAL_SYM));
+ const int max_combine_failures = 32;
+ if (try_combine ||
+ bin_info[bin_id].num_combine_failures >= max_combine_failures) {
+ // move the (better) merged histogram to its final slot
+ HistogramSwap(&cur_combo, &histograms[first]);
+ HistogramSetRemoveHistogram(image_histo, idx, num_used);
+ cluster_mappings[clusters[idx]] = clusters[first];
+ } else {
+ ++bin_info[bin_id].num_combine_failures;
+ }
+ }
+ }
+ }
+ if (low_effort) {
+ // for low_effort case, update the final cost when everything is merged
+ for (idx = 0; idx < image_histo->size; ++idx) {
+ if (histograms[idx] == NULL) continue;
+ UpdateHistogramCost(histograms[idx]);
+ }
+ }
+}
+
+// Implement a Lehmer random number generator with a multiplicative constant of
+// 48271 and a modulo constant of 2^31 - 1.
+static uint32_t MyRand(uint32_t* const seed) {
+ *seed = (uint32_t)(((uint64_t)(*seed) * 48271u) % 2147483647u);
+ assert(*seed > 0);
+ return *seed;
+}
+
+// -----------------------------------------------------------------------------
+// Histogram pairs priority queue
+
+// Pair of histograms. Negative idx1 value means that pair is out-of-date.
+typedef struct {
+ int idx1;
+ int idx2;
+ float cost_diff;
+ float cost_combo;
+} HistogramPair;
+
+typedef struct {
+ HistogramPair* queue;
+ int size;
+ int max_size;
+} HistoQueue;
+
+static int HistoQueueInit(HistoQueue* const histo_queue, const int max_size) {
+ histo_queue->size = 0;
+ histo_queue->max_size = max_size;
+ // We allocate max_size + 1 because the last element at index "size" is
+ // used as temporary data (and it could be up to max_size).
+ histo_queue->queue = (HistogramPair*)WebPSafeMalloc(
+ histo_queue->max_size + 1, sizeof(*histo_queue->queue));
+ return histo_queue->queue != NULL;
+}
+
+static void HistoQueueClear(HistoQueue* const histo_queue) {
+ assert(histo_queue != NULL);
+ WebPSafeFree(histo_queue->queue);
+ histo_queue->size = 0;
+ histo_queue->max_size = 0;
+}
+
+// Pop a specific pair in the queue by replacing it with the last one
+// and shrinking the queue.
+static void HistoQueuePopPair(HistoQueue* const histo_queue,
+ HistogramPair* const pair) {
+ assert(pair >= histo_queue->queue &&
+ pair < (histo_queue->queue + histo_queue->size));
+ assert(histo_queue->size > 0);
+ *pair = histo_queue->queue[histo_queue->size - 1];
+ --histo_queue->size;
+}
+
+// Check whether a pair in the queue should be updated as head or not.
+static void HistoQueueUpdateHead(HistoQueue* const histo_queue,
+ HistogramPair* const pair) {
+ assert(pair->cost_diff < 0.);
+ assert(pair >= histo_queue->queue &&
+ pair < (histo_queue->queue + histo_queue->size));
+ assert(histo_queue->size > 0);
+ if (pair->cost_diff < histo_queue->queue[0].cost_diff) {
+ // Replace the best pair.
+ const HistogramPair tmp = histo_queue->queue[0];
+ histo_queue->queue[0] = *pair;
+ *pair = tmp;
+ }
+}
+
+// Update the cost diff and combo of a pair of histograms. This needs to be
+// called when the the histograms have been merged with a third one.
+static void HistoQueueUpdatePair(const VP8LHistogram* const h1,
+ const VP8LHistogram* const h2, float threshold,
+ HistogramPair* const pair) {
+ const float sum_cost = h1->bit_cost_ + h2->bit_cost_;
+ pair->cost_combo = 0.;
+ GetCombinedHistogramEntropy(h1, h2, sum_cost + threshold, &pair->cost_combo);
+ pair->cost_diff = pair->cost_combo - sum_cost;
+}
+
+// Create a pair from indices "idx1" and "idx2" provided its cost
+// is inferior to "threshold", a negative entropy.
+// It returns the cost of the pair, or 0. if it superior to threshold.
+static float HistoQueuePush(HistoQueue* const histo_queue,
+ VP8LHistogram** const histograms, int idx1,
+ int idx2, float threshold) {
+ const VP8LHistogram* h1;
+ const VP8LHistogram* h2;
+ HistogramPair pair;
+
+ // Stop here if the queue is full.
+ if (histo_queue->size == histo_queue->max_size) return 0.;
+ assert(threshold <= 0.);
+ if (idx1 > idx2) {
+ const int tmp = idx2;
+ idx2 = idx1;
+ idx1 = tmp;
+ }
+ pair.idx1 = idx1;
+ pair.idx2 = idx2;
+ h1 = histograms[idx1];
+ h2 = histograms[idx2];
+
+ HistoQueueUpdatePair(h1, h2, threshold, &pair);
+
+ // Do not even consider the pair if it does not improve the entropy.
+ if (pair.cost_diff >= threshold) return 0.;
+
+ histo_queue->queue[histo_queue->size++] = pair;
+ HistoQueueUpdateHead(histo_queue, &histo_queue->queue[histo_queue->size - 1]);
+
+ return pair.cost_diff;
+}
+
+// -----------------------------------------------------------------------------
+
+// Combines histograms by continuously choosing the one with the highest cost
+// reduction.
+static int HistogramCombineGreedy(VP8LHistogramSet* const image_histo,
+ int* const num_used) {
+ int ok = 0;
+ const int image_histo_size = image_histo->size;
+ int i, j;
+ VP8LHistogram** const histograms = image_histo->histograms;
+ // Priority queue of histogram pairs.
+ HistoQueue histo_queue;
+
+ // image_histo_size^2 for the queue size is safe. If you look at
+ // HistogramCombineGreedy, and imagine that UpdateQueueFront always pushes
+ // data to the queue, you insert at most:
+ // - image_histo_size*(image_histo_size-1)/2 (the first two for loops)
+ // - image_histo_size - 1 in the last for loop at the first iteration of
+ // the while loop, image_histo_size - 2 at the second iteration ...
+ // therefore image_histo_size*(image_histo_size-1)/2 overall too
+ if (!HistoQueueInit(&histo_queue, image_histo_size * image_histo_size)) {
+ goto End;
+ }
+
+ for (i = 0; i < image_histo_size; ++i) {
+ if (image_histo->histograms[i] == NULL) continue;
+ for (j = i + 1; j < image_histo_size; ++j) {
+ // Initialize queue.
+ if (image_histo->histograms[j] == NULL) continue;
+ HistoQueuePush(&histo_queue, histograms, i, j, 0.);
+ }
+ }
+
+ while (histo_queue.size > 0) {
+ const int idx1 = histo_queue.queue[0].idx1;
+ const int idx2 = histo_queue.queue[0].idx2;
+ HistogramAdd(histograms[idx2], histograms[idx1], histograms[idx1]);
+ histograms[idx1]->bit_cost_ = histo_queue.queue[0].cost_combo;
+
+ // Remove merged histogram.
+ HistogramSetRemoveHistogram(image_histo, idx2, num_used);
+
+ // Remove pairs intersecting the just combined best pair.
+ for (i = 0; i < histo_queue.size;) {
+ HistogramPair* const p = histo_queue.queue + i;
+ if (p->idx1 == idx1 || p->idx2 == idx1 ||
+ p->idx1 == idx2 || p->idx2 == idx2) {
+ HistoQueuePopPair(&histo_queue, p);
+ } else {
+ HistoQueueUpdateHead(&histo_queue, p);
+ ++i;
+ }
+ }
+
+ // Push new pairs formed with combined histogram to the queue.
+ for (i = 0; i < image_histo->size; ++i) {
+ if (i == idx1 || image_histo->histograms[i] == NULL) continue;
+ HistoQueuePush(&histo_queue, image_histo->histograms, idx1, i, 0.);
+ }
+ }
+
+ ok = 1;
+
+ End:
+ HistoQueueClear(&histo_queue);
+ return ok;
+}
+
+// Perform histogram aggregation using a stochastic approach.
+// 'do_greedy' is set to 1 if a greedy approach needs to be performed
+// afterwards, 0 otherwise.
+static int PairComparison(const void* idx1, const void* idx2) {
+ // To be used with bsearch: <0 when *idx1<*idx2, >0 if >, 0 when ==.
+ return (*(int*) idx1 - *(int*) idx2);
+}
+static int HistogramCombineStochastic(VP8LHistogramSet* const image_histo,
+ int* const num_used, int min_cluster_size,
+ int* const do_greedy) {
+ int j, iter;
+ uint32_t seed = 1;
+ int tries_with_no_success = 0;
+ const int outer_iters = *num_used;
+ const int num_tries_no_success = outer_iters / 2;
+ VP8LHistogram** const histograms = image_histo->histograms;
+ // Priority queue of histogram pairs. Its size of 'kHistoQueueSize'
+ // impacts the quality of the compression and the speed: the smaller the
+ // faster but the worse for the compression.
+ HistoQueue histo_queue;
+ const int kHistoQueueSize = 9;
+ int ok = 0;
+ // mapping from an index in image_histo with no NULL histogram to the full
+ // blown image_histo.
+ int* mappings;
+
+ if (*num_used < min_cluster_size) {
+ *do_greedy = 1;
+ return 1;
+ }
+
+ mappings = (int*) WebPSafeMalloc(*num_used, sizeof(*mappings));
+ if (mappings == NULL) return 0;
+ if (!HistoQueueInit(&histo_queue, kHistoQueueSize)) goto End;
+ // Fill the initial mapping.
+ for (j = 0, iter = 0; iter < image_histo->size; ++iter) {
+ if (histograms[iter] == NULL) continue;
+ mappings[j++] = iter;
+ }
+ assert(j == *num_used);
+
+ // Collapse similar histograms in 'image_histo'.
+ for (iter = 0;
+ iter < outer_iters && *num_used >= min_cluster_size &&
+ ++tries_with_no_success < num_tries_no_success;
+ ++iter) {
+ int* mapping_index;
+ float best_cost =
+ (histo_queue.size == 0) ? 0.f : histo_queue.queue[0].cost_diff;
+ int best_idx1 = -1, best_idx2 = 1;
+ const uint32_t rand_range = (*num_used - 1) * (*num_used);
+ // (*num_used) / 2 was chosen empirically. Less means faster but worse
+ // compression.
+ const int num_tries = (*num_used) / 2;
+
+ // Pick random samples.
+ for (j = 0; *num_used >= 2 && j < num_tries; ++j) {
+ float curr_cost;
+ // Choose two different histograms at random and try to combine them.
+ const uint32_t tmp = MyRand(&seed) % rand_range;
+ uint32_t idx1 = tmp / (*num_used - 1);
+ uint32_t idx2 = tmp % (*num_used - 1);
+ if (idx2 >= idx1) ++idx2;
+ idx1 = mappings[idx1];
+ idx2 = mappings[idx2];
+
+ // Calculate cost reduction on combination.
+ curr_cost =
+ HistoQueuePush(&histo_queue, histograms, idx1, idx2, best_cost);
+ if (curr_cost < 0) { // found a better pair?
+ best_cost = curr_cost;
+ // Empty the queue if we reached full capacity.
+ if (histo_queue.size == histo_queue.max_size) break;
+ }
+ }
+ if (histo_queue.size == 0) continue;
+
+ // Get the best histograms.
+ best_idx1 = histo_queue.queue[0].idx1;
+ best_idx2 = histo_queue.queue[0].idx2;
+ assert(best_idx1 < best_idx2);
+ // Pop best_idx2 from mappings.
+ mapping_index = (int*) bsearch(&best_idx2, mappings, *num_used,
+ sizeof(best_idx2), &PairComparison);
+ assert(mapping_index != NULL);
+ memmove(mapping_index, mapping_index + 1, sizeof(*mapping_index) *
+ ((*num_used) - (mapping_index - mappings) - 1));
+ // Merge the histograms and remove best_idx2 from the queue.
+ HistogramAdd(histograms[best_idx2], histograms[best_idx1],
+ histograms[best_idx1]);
+ histograms[best_idx1]->bit_cost_ = histo_queue.queue[0].cost_combo;
+ HistogramSetRemoveHistogram(image_histo, best_idx2, num_used);
+ // Parse the queue and update each pair that deals with best_idx1,
+ // best_idx2 or image_histo_size.
+ for (j = 0; j < histo_queue.size;) {
+ HistogramPair* const p = histo_queue.queue + j;
+ const int is_idx1_best = p->idx1 == best_idx1 || p->idx1 == best_idx2;
+ const int is_idx2_best = p->idx2 == best_idx1 || p->idx2 == best_idx2;
+ int do_eval = 0;
+ // The front pair could have been duplicated by a random pick so
+ // check for it all the time nevertheless.
+ if (is_idx1_best && is_idx2_best) {
+ HistoQueuePopPair(&histo_queue, p);
+ continue;
+ }
+ // Any pair containing one of the two best indices should only refer to
+ // best_idx1. Its cost should also be updated.
+ if (is_idx1_best) {
+ p->idx1 = best_idx1;
+ do_eval = 1;
+ } else if (is_idx2_best) {
+ p->idx2 = best_idx1;
+ do_eval = 1;
+ }
+ // Make sure the index order is respected.
+ if (p->idx1 > p->idx2) {
+ const int tmp = p->idx2;
+ p->idx2 = p->idx1;
+ p->idx1 = tmp;
+ }
+ if (do_eval) {
+ // Re-evaluate the cost of an updated pair.
+ HistoQueueUpdatePair(histograms[p->idx1], histograms[p->idx2], 0., p);
+ if (p->cost_diff >= 0.) {
+ HistoQueuePopPair(&histo_queue, p);
+ continue;
+ }
+ }
+ HistoQueueUpdateHead(&histo_queue, p);
+ ++j;
+ }
+ tries_with_no_success = 0;
+ }
+ *do_greedy = (*num_used <= min_cluster_size);
+ ok = 1;
+
+ End:
+ HistoQueueClear(&histo_queue);
+ WebPSafeFree(mappings);
+ return ok;
+}
+
+// -----------------------------------------------------------------------------
+// Histogram refinement
+
+// Find the best 'out' histogram for each of the 'in' histograms.
+// At call-time, 'out' contains the histograms of the clusters.
+// Note: we assume that out[]->bit_cost_ is already up-to-date.
+static void HistogramRemap(const VP8LHistogramSet* const in,
+ VP8LHistogramSet* const out,
+ uint16_t* const symbols) {
+ int i;
+ VP8LHistogram** const in_histo = in->histograms;
+ VP8LHistogram** const out_histo = out->histograms;
+ const int in_size = out->max_size;
+ const int out_size = out->size;
+ if (out_size > 1) {
+ for (i = 0; i < in_size; ++i) {
+ int best_out = 0;
+ float best_bits = MAX_BIT_COST;
+ int k;
+ if (in_histo[i] == NULL) {
+ // Arbitrarily set to the previous value if unused to help future LZ77.
+ symbols[i] = symbols[i - 1];
+ continue;
+ }
+ for (k = 0; k < out_size; ++k) {
+ float cur_bits;
+ cur_bits = HistogramAddThresh(out_histo[k], in_histo[i], best_bits);
+ if (k == 0 || cur_bits < best_bits) {
+ best_bits = cur_bits;
+ best_out = k;
+ }
+ }
+ symbols[i] = best_out;
+ }
+ } else {
+ assert(out_size == 1);
+ for (i = 0; i < in_size; ++i) {
+ symbols[i] = 0;
+ }
+ }
+
+ // Recompute each out based on raw and symbols.
+ VP8LHistogramSetClear(out);
+ out->size = out_size;
+
+ for (i = 0; i < in_size; ++i) {
+ int idx;
+ if (in_histo[i] == NULL) continue;
+ idx = symbols[i];
+ HistogramAdd(in_histo[i], out_histo[idx], out_histo[idx]);
+ }
+}
+
+static float GetCombineCostFactor(int histo_size, int quality) {
+ float combine_cost_factor = 0.16f;
+ if (quality < 90) {
+ if (histo_size > 256) combine_cost_factor /= 2.f;
+ if (histo_size > 512) combine_cost_factor /= 2.f;
+ if (histo_size > 1024) combine_cost_factor /= 2.f;
+ if (quality <= 50) combine_cost_factor /= 2.f;
+ }
+ return combine_cost_factor;
+}
+
+// Given a HistogramSet 'set', the mapping of clusters 'cluster_mapping' and the
+// current assignment of the cells in 'symbols', merge the clusters and
+// assign the smallest possible clusters values.
+static void OptimizeHistogramSymbols(const VP8LHistogramSet* const set,
+ uint16_t* const cluster_mappings,
+ int num_clusters,
+ uint16_t* const cluster_mappings_tmp,
+ uint16_t* const symbols) {
+ int i, cluster_max;
+ int do_continue = 1;
+ // First, assign the lowest cluster to each pixel.
+ while (do_continue) {
+ do_continue = 0;
+ for (i = 0; i < num_clusters; ++i) {
+ int k;
+ k = cluster_mappings[i];
+ while (k != cluster_mappings[k]) {
+ cluster_mappings[k] = cluster_mappings[cluster_mappings[k]];
+ k = cluster_mappings[k];
+ }
+ if (k != cluster_mappings[i]) {
+ do_continue = 1;
+ cluster_mappings[i] = k;
+ }
+ }
+ }
+ // Create a mapping from a cluster id to its minimal version.
+ cluster_max = 0;
+ memset(cluster_mappings_tmp, 0,
+ set->max_size * sizeof(*cluster_mappings_tmp));
+ assert(cluster_mappings[0] == 0);
+ // Re-map the ids.
+ for (i = 0; i < set->max_size; ++i) {
+ int cluster;
+ if (symbols[i] == kInvalidHistogramSymbol) continue;
+ cluster = cluster_mappings[symbols[i]];
+ assert(symbols[i] < num_clusters);
+ if (cluster > 0 && cluster_mappings_tmp[cluster] == 0) {
+ ++cluster_max;
+ cluster_mappings_tmp[cluster] = cluster_max;
+ }
+ symbols[i] = cluster_mappings_tmp[cluster];
+ }
+
+ // Make sure all cluster values are used.
+ cluster_max = 0;
+ for (i = 0; i < set->max_size; ++i) {
+ if (symbols[i] == kInvalidHistogramSymbol) continue;
+ if (symbols[i] <= cluster_max) continue;
+ ++cluster_max;
+ assert(symbols[i] == cluster_max);
+ }
+}
+
+static void RemoveEmptyHistograms(VP8LHistogramSet* const image_histo) {
+ uint32_t size;
+ int i;
+ for (i = 0, size = 0; i < image_histo->size; ++i) {
+ if (image_histo->histograms[i] == NULL) continue;
+ image_histo->histograms[size++] = image_histo->histograms[i];
+ }
+ image_histo->size = size;
+}
+
+int VP8LGetHistoImageSymbols(int xsize, int ysize,
+ const VP8LBackwardRefs* const refs, int quality,
+ int low_effort, int histogram_bits, int cache_bits,
+ VP8LHistogramSet* const image_histo,
+ VP8LHistogram* const tmp_histo,
+ uint16_t* const histogram_symbols,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent) {
+ const int histo_xsize =
+ histogram_bits ? VP8LSubSampleSize(xsize, histogram_bits) : 1;
+ const int histo_ysize =
+ histogram_bits ? VP8LSubSampleSize(ysize, histogram_bits) : 1;
+ const int image_histo_raw_size = histo_xsize * histo_ysize;
+ VP8LHistogramSet* const orig_histo =
+ VP8LAllocateHistogramSet(image_histo_raw_size, cache_bits);
+ // Don't attempt linear bin-partition heuristic for
+ // histograms of small sizes (as bin_map will be very sparse) and
+ // maximum quality q==100 (to preserve the compression gains at that level).
+ const int entropy_combine_num_bins = low_effort ? NUM_PARTITIONS : BIN_SIZE;
+ int entropy_combine;
+ uint16_t* const map_tmp =
+ WebPSafeMalloc(2 * image_histo_raw_size, sizeof(map_tmp));
+ uint16_t* const cluster_mappings = map_tmp + image_histo_raw_size;
+ int num_used = image_histo_raw_size;
+ if (orig_histo == NULL || map_tmp == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // Construct the histograms from backward references.
+ HistogramBuild(xsize, histogram_bits, refs, orig_histo);
+ // Copies the histograms and computes its bit_cost.
+ // histogram_symbols is optimized
+ HistogramCopyAndAnalyze(orig_histo, image_histo, &num_used,
+ histogram_symbols);
+
+ entropy_combine =
+ (num_used > entropy_combine_num_bins * 2) && (quality < 100);
+
+ if (entropy_combine) {
+ uint16_t* const bin_map = map_tmp;
+ const float combine_cost_factor =
+ GetCombineCostFactor(image_histo_raw_size, quality);
+ const uint32_t num_clusters = num_used;
+
+ HistogramAnalyzeEntropyBin(image_histo, bin_map, low_effort);
+ // Collapse histograms with similar entropy.
+ HistogramCombineEntropyBin(
+ image_histo, &num_used, histogram_symbols, cluster_mappings, tmp_histo,
+ bin_map, entropy_combine_num_bins, combine_cost_factor, low_effort);
+ OptimizeHistogramSymbols(image_histo, cluster_mappings, num_clusters,
+ map_tmp, histogram_symbols);
+ }
+
+ // Don't combine the histograms using stochastic and greedy heuristics for
+ // low-effort compression mode.
+ if (!low_effort || !entropy_combine) {
+ const float x = quality / 100.f;
+ // cubic ramp between 1 and MAX_HISTO_GREEDY:
+ const int threshold_size = (int)(1 + (x * x * x) * (MAX_HISTO_GREEDY - 1));
+ int do_greedy;
+ if (!HistogramCombineStochastic(image_histo, &num_used, threshold_size,
+ &do_greedy)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ if (do_greedy) {
+ RemoveEmptyHistograms(image_histo);
+ if (!HistogramCombineGreedy(image_histo, &num_used)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ }
+ }
+
+ // Find the optimal map from original histograms to the final ones.
+ RemoveEmptyHistograms(image_histo);
+ HistogramRemap(orig_histo, image_histo, histogram_symbols);
+
+ if (!WebPReportProgress(pic, *percent + percent_range, percent)) {
+ goto Error;
+ }
+
+ Error:
+ VP8LFreeHistogramSet(orig_histo);
+ WebPSafeFree(map_tmp);
+ return (pic->error_code == VP8_ENC_OK);
+}
diff --git a/media/libwebp/src/enc/histogram_enc.h b/media/libwebp/src/enc/histogram_enc.h
new file mode 100644
index 0000000000..4c0bb97464
--- /dev/null
+++ b/media/libwebp/src/enc/histogram_enc.h
@@ -0,0 +1,130 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+//
+// Models the histograms of literal and distance codes.
+
+#ifndef WEBP_ENC_HISTOGRAM_ENC_H_
+#define WEBP_ENC_HISTOGRAM_ENC_H_
+
+#include <string.h>
+
+#include "src/enc/backward_references_enc.h"
+#include "src/webp/format_constants.h"
+#include "src/webp/types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Not a trivial literal symbol.
+#define VP8L_NON_TRIVIAL_SYM (0xffffffff)
+
+// A simple container for histograms of data.
+typedef struct {
+ // literal_ contains green literal, palette-code and
+ // copy-length-prefix histogram
+ uint32_t* literal_; // Pointer to the allocated buffer for literal.
+ uint32_t red_[NUM_LITERAL_CODES];
+ uint32_t blue_[NUM_LITERAL_CODES];
+ uint32_t alpha_[NUM_LITERAL_CODES];
+ // Backward reference prefix-code histogram.
+ uint32_t distance_[NUM_DISTANCE_CODES];
+ int palette_code_bits_;
+ uint32_t trivial_symbol_; // True, if histograms for Red, Blue & Alpha
+ // literal symbols are single valued.
+ float bit_cost_; // cached value of bit cost.
+ float literal_cost_; // Cached values of dominant entropy costs:
+ float red_cost_; // literal, red & blue.
+ float blue_cost_;
+ uint8_t is_used_[5]; // 5 for literal, red, blue, alpha, distance
+} VP8LHistogram;
+
+// Collection of histograms with fixed capacity, allocated as one
+// big memory chunk. Can be destroyed by calling WebPSafeFree().
+typedef struct {
+ int size; // number of slots currently in use
+ int max_size; // maximum capacity
+ VP8LHistogram** histograms;
+} VP8LHistogramSet;
+
+// Create the histogram.
+//
+// The input data is the PixOrCopy data, which models the literals, stop
+// codes and backward references (both distances and lengths). Also: if
+// palette_code_bits is >= 0, initialize the histogram with this value.
+void VP8LHistogramCreate(VP8LHistogram* const p,
+ const VP8LBackwardRefs* const refs,
+ int palette_code_bits);
+
+// Return the size of the histogram for a given cache_bits.
+int VP8LGetHistogramSize(int cache_bits);
+
+// Set the palette_code_bits and reset the stats.
+// If init_arrays is true, the arrays are also filled with 0's.
+void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits,
+ int init_arrays);
+
+// Collect all the references into a histogram (without reset)
+void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
+ VP8LHistogram* const histo);
+
+// Free the memory allocated for the histogram.
+void VP8LFreeHistogram(VP8LHistogram* const histo);
+
+// Free the memory allocated for the histogram set.
+void VP8LFreeHistogramSet(VP8LHistogramSet* const histo);
+
+// Allocate an array of pointer to histograms, allocated and initialized
+// using 'cache_bits'. Return NULL in case of memory error.
+VP8LHistogramSet* VP8LAllocateHistogramSet(int size, int cache_bits);
+
+// Set the histograms in set to 0.
+void VP8LHistogramSetClear(VP8LHistogramSet* const set);
+
+// Allocate and initialize histogram object with specified 'cache_bits'.
+// Returns NULL in case of memory error.
+// Special case of VP8LAllocateHistogramSet, with size equals 1.
+VP8LHistogram* VP8LAllocateHistogram(int cache_bits);
+
+// Accumulate a token 'v' into a histogram.
+void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const histo,
+ const PixOrCopy* const v,
+ int (*const distance_modifier)(int, int),
+ int distance_modifier_arg0);
+
+static WEBP_INLINE int VP8LHistogramNumCodes(int palette_code_bits) {
+ return NUM_LITERAL_CODES + NUM_LENGTH_CODES +
+ ((palette_code_bits > 0) ? (1 << palette_code_bits) : 0);
+}
+
+// Builds the histogram image. pic and percent are for progress.
+// Returns false in case of error (stored in pic->error_code).
+int VP8LGetHistoImageSymbols(int xsize, int ysize,
+ const VP8LBackwardRefs* const refs, int quality,
+ int low_effort, int histogram_bits, int cache_bits,
+ VP8LHistogramSet* const image_histo,
+ VP8LHistogram* const tmp_histo,
+ uint16_t* const histogram_symbols,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent);
+
+// Returns the entropy for the symbols in the input array.
+float VP8LBitsEntropy(const uint32_t* const array, int n);
+
+// Estimate how many bits the combined entropy of literals and distance
+// approximately maps to.
+float VP8LHistogramEstimateBits(VP8LHistogram* const p);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // WEBP_ENC_HISTOGRAM_ENC_H_
diff --git a/media/libwebp/src/enc/iterator_enc.c b/media/libwebp/src/enc/iterator_enc.c
new file mode 100644
index 0000000000..29f91d8315
--- /dev/null
+++ b/media/libwebp/src/enc/iterator_enc.c
@@ -0,0 +1,459 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// VP8Iterator: block iterator
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <string.h>
+
+#include "src/enc/vp8i_enc.h"
+
+//------------------------------------------------------------------------------
+// VP8Iterator
+//------------------------------------------------------------------------------
+
+static void InitLeft(VP8EncIterator* const it) {
+ it->y_left_[-1] = it->u_left_[-1] = it->v_left_[-1] =
+ (it->y_ > 0) ? 129 : 127;
+ memset(it->y_left_, 129, 16);
+ memset(it->u_left_, 129, 8);
+ memset(it->v_left_, 129, 8);
+ it->left_nz_[8] = 0;
+ if (it->top_derr_ != NULL) {
+ memset(&it->left_derr_, 0, sizeof(it->left_derr_));
+ }
+}
+
+static void InitTop(VP8EncIterator* const it) {
+ const VP8Encoder* const enc = it->enc_;
+ const size_t top_size = enc->mb_w_ * 16;
+ memset(enc->y_top_, 127, 2 * top_size);
+ memset(enc->nz_, 0, enc->mb_w_ * sizeof(*enc->nz_));
+ if (enc->top_derr_ != NULL) {
+ memset(enc->top_derr_, 0, enc->mb_w_ * sizeof(*enc->top_derr_));
+ }
+}
+
+void VP8IteratorSetRow(VP8EncIterator* const it, int y) {
+ VP8Encoder* const enc = it->enc_;
+ it->x_ = 0;
+ it->y_ = y;
+ it->bw_ = &enc->parts_[y & (enc->num_parts_ - 1)];
+ it->preds_ = enc->preds_ + y * 4 * enc->preds_w_;
+ it->nz_ = enc->nz_;
+ it->mb_ = enc->mb_info_ + y * enc->mb_w_;
+ it->y_top_ = enc->y_top_;
+ it->uv_top_ = enc->uv_top_;
+ InitLeft(it);
+}
+
+void VP8IteratorReset(VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ VP8IteratorSetRow(it, 0);
+ VP8IteratorSetCountDown(it, enc->mb_w_ * enc->mb_h_); // default
+ InitTop(it);
+ memset(it->bit_count_, 0, sizeof(it->bit_count_));
+ it->do_trellis_ = 0;
+}
+
+void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down) {
+ it->count_down_ = it->count_down0_ = count_down;
+}
+
+int VP8IteratorIsDone(const VP8EncIterator* const it) {
+ return (it->count_down_ <= 0);
+}
+
+void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it) {
+ it->enc_ = enc;
+ it->yuv_in_ = (uint8_t*)WEBP_ALIGN(it->yuv_mem_);
+ it->yuv_out_ = it->yuv_in_ + YUV_SIZE_ENC;
+ it->yuv_out2_ = it->yuv_out_ + YUV_SIZE_ENC;
+ it->yuv_p_ = it->yuv_out2_ + YUV_SIZE_ENC;
+ it->lf_stats_ = enc->lf_stats_;
+ it->percent0_ = enc->percent_;
+ it->y_left_ = (uint8_t*)WEBP_ALIGN(it->yuv_left_mem_ + 1);
+ it->u_left_ = it->y_left_ + 16 + 16;
+ it->v_left_ = it->u_left_ + 16;
+ it->top_derr_ = enc->top_derr_;
+ VP8IteratorReset(it);
+}
+
+int VP8IteratorProgress(const VP8EncIterator* const it, int delta) {
+ VP8Encoder* const enc = it->enc_;
+ if (delta && enc->pic_->progress_hook != NULL) {
+ const int done = it->count_down0_ - it->count_down_;
+ const int percent = (it->count_down0_ <= 0)
+ ? it->percent0_
+ : it->percent0_ + delta * done / it->count_down0_;
+ return WebPReportProgress(enc->pic_, percent, &enc->percent_);
+ }
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+// Import the source samples into the cache. Takes care of replicating
+// boundary pixels if necessary.
+
+static WEBP_INLINE int MinSize(int a, int b) { return (a < b) ? a : b; }
+
+static void ImportBlock(const uint8_t* src, int src_stride,
+ uint8_t* dst, int w, int h, int size) {
+ int i;
+ for (i = 0; i < h; ++i) {
+ memcpy(dst, src, w);
+ if (w < size) {
+ memset(dst + w, dst[w - 1], size - w);
+ }
+ dst += BPS;
+ src += src_stride;
+ }
+ for (i = h; i < size; ++i) {
+ memcpy(dst, dst - BPS, size);
+ dst += BPS;
+ }
+}
+
+static void ImportLine(const uint8_t* src, int src_stride,
+ uint8_t* dst, int len, int total_len) {
+ int i;
+ for (i = 0; i < len; ++i, src += src_stride) dst[i] = *src;
+ for (; i < total_len; ++i) dst[i] = dst[len - 1];
+}
+
+void VP8IteratorImport(VP8EncIterator* const it, uint8_t* const tmp_32) {
+ const VP8Encoder* const enc = it->enc_;
+ const int x = it->x_, y = it->y_;
+ const WebPPicture* const pic = enc->pic_;
+ const uint8_t* const ysrc = pic->y + (y * pic->y_stride + x) * 16;
+ const uint8_t* const usrc = pic->u + (y * pic->uv_stride + x) * 8;
+ const uint8_t* const vsrc = pic->v + (y * pic->uv_stride + x) * 8;
+ const int w = MinSize(pic->width - x * 16, 16);
+ const int h = MinSize(pic->height - y * 16, 16);
+ const int uv_w = (w + 1) >> 1;
+ const int uv_h = (h + 1) >> 1;
+
+ ImportBlock(ysrc, pic->y_stride, it->yuv_in_ + Y_OFF_ENC, w, h, 16);
+ ImportBlock(usrc, pic->uv_stride, it->yuv_in_ + U_OFF_ENC, uv_w, uv_h, 8);
+ ImportBlock(vsrc, pic->uv_stride, it->yuv_in_ + V_OFF_ENC, uv_w, uv_h, 8);
+
+ if (tmp_32 == NULL) return;
+
+ // Import source (uncompressed) samples into boundary.
+ if (x == 0) {
+ InitLeft(it);
+ } else {
+ if (y == 0) {
+ it->y_left_[-1] = it->u_left_[-1] = it->v_left_[-1] = 127;
+ } else {
+ it->y_left_[-1] = ysrc[- 1 - pic->y_stride];
+ it->u_left_[-1] = usrc[- 1 - pic->uv_stride];
+ it->v_left_[-1] = vsrc[- 1 - pic->uv_stride];
+ }
+ ImportLine(ysrc - 1, pic->y_stride, it->y_left_, h, 16);
+ ImportLine(usrc - 1, pic->uv_stride, it->u_left_, uv_h, 8);
+ ImportLine(vsrc - 1, pic->uv_stride, it->v_left_, uv_h, 8);
+ }
+
+ it->y_top_ = tmp_32 + 0;
+ it->uv_top_ = tmp_32 + 16;
+ if (y == 0) {
+ memset(tmp_32, 127, 32 * sizeof(*tmp_32));
+ } else {
+ ImportLine(ysrc - pic->y_stride, 1, tmp_32, w, 16);
+ ImportLine(usrc - pic->uv_stride, 1, tmp_32 + 16, uv_w, 8);
+ ImportLine(vsrc - pic->uv_stride, 1, tmp_32 + 16 + 8, uv_w, 8);
+ }
+}
+
+//------------------------------------------------------------------------------
+// Copy back the compressed samples into user space if requested.
+
+static void ExportBlock(const uint8_t* src, uint8_t* dst, int dst_stride,
+ int w, int h) {
+ while (h-- > 0) {
+ memcpy(dst, src, w);
+ dst += dst_stride;
+ src += BPS;
+ }
+}
+
+void VP8IteratorExport(const VP8EncIterator* const it) {
+ const VP8Encoder* const enc = it->enc_;
+ if (enc->config_->show_compressed) {
+ const int x = it->x_, y = it->y_;
+ const uint8_t* const ysrc = it->yuv_out_ + Y_OFF_ENC;
+ const uint8_t* const usrc = it->yuv_out_ + U_OFF_ENC;
+ const uint8_t* const vsrc = it->yuv_out_ + V_OFF_ENC;
+ const WebPPicture* const pic = enc->pic_;
+ uint8_t* const ydst = pic->y + (y * pic->y_stride + x) * 16;
+ uint8_t* const udst = pic->u + (y * pic->uv_stride + x) * 8;
+ uint8_t* const vdst = pic->v + (y * pic->uv_stride + x) * 8;
+ int w = (pic->width - x * 16);
+ int h = (pic->height - y * 16);
+
+ if (w > 16) w = 16;
+ if (h > 16) h = 16;
+
+ // Luma plane
+ ExportBlock(ysrc, ydst, pic->y_stride, w, h);
+
+ { // U/V planes
+ const int uv_w = (w + 1) >> 1;
+ const int uv_h = (h + 1) >> 1;
+ ExportBlock(usrc, udst, pic->uv_stride, uv_w, uv_h);
+ ExportBlock(vsrc, vdst, pic->uv_stride, uv_w, uv_h);
+ }
+ }
+}
+
+//------------------------------------------------------------------------------
+// Non-zero contexts setup/teardown
+
+// Nz bits:
+// 0 1 2 3 Y
+// 4 5 6 7
+// 8 9 10 11
+// 12 13 14 15
+// 16 17 U
+// 18 19
+// 20 21 V
+// 22 23
+// 24 DC-intra16
+
+// Convert packed context to byte array
+#define BIT(nz, n) (!!((nz) & (1 << (n))))
+
+void VP8IteratorNzToBytes(VP8EncIterator* const it) {
+ const int tnz = it->nz_[0], lnz = it->nz_[-1];
+ int* const top_nz = it->top_nz_;
+ int* const left_nz = it->left_nz_;
+
+ // Top-Y
+ top_nz[0] = BIT(tnz, 12);
+ top_nz[1] = BIT(tnz, 13);
+ top_nz[2] = BIT(tnz, 14);
+ top_nz[3] = BIT(tnz, 15);
+ // Top-U
+ top_nz[4] = BIT(tnz, 18);
+ top_nz[5] = BIT(tnz, 19);
+ // Top-V
+ top_nz[6] = BIT(tnz, 22);
+ top_nz[7] = BIT(tnz, 23);
+ // DC
+ top_nz[8] = BIT(tnz, 24);
+
+ // left-Y
+ left_nz[0] = BIT(lnz, 3);
+ left_nz[1] = BIT(lnz, 7);
+ left_nz[2] = BIT(lnz, 11);
+ left_nz[3] = BIT(lnz, 15);
+ // left-U
+ left_nz[4] = BIT(lnz, 17);
+ left_nz[5] = BIT(lnz, 19);
+ // left-V
+ left_nz[6] = BIT(lnz, 21);
+ left_nz[7] = BIT(lnz, 23);
+ // left-DC is special, iterated separately
+}
+
+void VP8IteratorBytesToNz(VP8EncIterator* const it) {
+ uint32_t nz = 0;
+ const int* const top_nz = it->top_nz_;
+ const int* const left_nz = it->left_nz_;
+ // top
+ nz |= (top_nz[0] << 12) | (top_nz[1] << 13);
+ nz |= (top_nz[2] << 14) | (top_nz[3] << 15);
+ nz |= (top_nz[4] << 18) | (top_nz[5] << 19);
+ nz |= (top_nz[6] << 22) | (top_nz[7] << 23);
+ nz |= (top_nz[8] << 24); // we propagate the _top_ bit, esp. for intra4
+ // left
+ nz |= (left_nz[0] << 3) | (left_nz[1] << 7);
+ nz |= (left_nz[2] << 11);
+ nz |= (left_nz[4] << 17) | (left_nz[6] << 21);
+
+ *it->nz_ = nz;
+}
+
+#undef BIT
+
+//------------------------------------------------------------------------------
+// Advance to the next position, doing the bookkeeping.
+
+void VP8IteratorSaveBoundary(VP8EncIterator* const it) {
+ VP8Encoder* const enc = it->enc_;
+ const int x = it->x_, y = it->y_;
+ const uint8_t* const ysrc = it->yuv_out_ + Y_OFF_ENC;
+ const uint8_t* const uvsrc = it->yuv_out_ + U_OFF_ENC;
+ if (x < enc->mb_w_ - 1) { // left
+ int i;
+ for (i = 0; i < 16; ++i) {
+ it->y_left_[i] = ysrc[15 + i * BPS];
+ }
+ for (i = 0; i < 8; ++i) {
+ it->u_left_[i] = uvsrc[7 + i * BPS];
+ it->v_left_[i] = uvsrc[15 + i * BPS];
+ }
+ // top-left (before 'top'!)
+ it->y_left_[-1] = it->y_top_[15];
+ it->u_left_[-1] = it->uv_top_[0 + 7];
+ it->v_left_[-1] = it->uv_top_[8 + 7];
+ }
+ if (y < enc->mb_h_ - 1) { // top
+ memcpy(it->y_top_, ysrc + 15 * BPS, 16);
+ memcpy(it->uv_top_, uvsrc + 7 * BPS, 8 + 8);
+ }
+}
+
+int VP8IteratorNext(VP8EncIterator* const it) {
+ if (++it->x_ == it->enc_->mb_w_) {
+ VP8IteratorSetRow(it, ++it->y_);
+ } else {
+ it->preds_ += 4;
+ it->mb_ += 1;
+ it->nz_ += 1;
+ it->y_top_ += 16;
+ it->uv_top_ += 16;
+ }
+ return (0 < --it->count_down_);
+}
+
+//------------------------------------------------------------------------------
+// Helper function to set mode properties
+
+void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode) {
+ uint8_t* preds = it->preds_;
+ int y;
+ for (y = 0; y < 4; ++y) {
+ memset(preds, mode, 4);
+ preds += it->enc_->preds_w_;
+ }
+ it->mb_->type_ = 1;
+}
+
+void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes) {
+ uint8_t* preds = it->preds_;
+ int y;
+ for (y = 4; y > 0; --y) {
+ memcpy(preds, modes, 4 * sizeof(*modes));
+ preds += it->enc_->preds_w_;
+ modes += 4;
+ }
+ it->mb_->type_ = 0;
+}
+
+void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode) {
+ it->mb_->uv_mode_ = mode;
+}
+
+void VP8SetSkip(const VP8EncIterator* const it, int skip) {
+ it->mb_->skip_ = skip;
+}
+
+void VP8SetSegment(const VP8EncIterator* const it, int segment) {
+ it->mb_->segment_ = segment;
+}
+
+//------------------------------------------------------------------------------
+// Intra4x4 sub-blocks iteration
+//
+// We store and update the boundary samples into an array of 37 pixels. They
+// are updated as we iterate and reconstructs each intra4x4 blocks in turn.
+// The position of the samples has the following snake pattern:
+//
+// 16|17 18 19 20|21 22 23 24|25 26 27 28|29 30 31 32|33 34 35 36 <- Top-right
+// --+-----------+-----------+-----------+-----------+
+// 15| 19| 23| 27| 31|
+// 14| 18| 22| 26| 30|
+// 13| 17| 21| 25| 29|
+// 12|13 14 15 16|17 18 19 20|21 22 23 24|25 26 27 28|
+// --+-----------+-----------+-----------+-----------+
+// 11| 15| 19| 23| 27|
+// 10| 14| 18| 22| 26|
+// 9| 13| 17| 21| 25|
+// 8| 9 10 11 12|13 14 15 16|17 18 19 20|21 22 23 24|
+// --+-----------+-----------+-----------+-----------+
+// 7| 11| 15| 19| 23|
+// 6| 10| 14| 18| 22|
+// 5| 9| 13| 17| 21|
+// 4| 5 6 7 8| 9 10 11 12|13 14 15 16|17 18 19 20|
+// --+-----------+-----------+-----------+-----------+
+// 3| 7| 11| 15| 19|
+// 2| 6| 10| 14| 18|
+// 1| 5| 9| 13| 17|
+// 0| 1 2 3 4| 5 6 7 8| 9 10 11 12|13 14 15 16|
+// --+-----------+-----------+-----------+-----------+
+
+// Array to record the position of the top sample to pass to the prediction
+// functions in dsp.c.
+static const uint8_t VP8TopLeftI4[16] = {
+ 17, 21, 25, 29,
+ 13, 17, 21, 25,
+ 9, 13, 17, 21,
+ 5, 9, 13, 17
+};
+
+void VP8IteratorStartI4(VP8EncIterator* const it) {
+ const VP8Encoder* const enc = it->enc_;
+ int i;
+
+ it->i4_ = 0; // first 4x4 sub-block
+ it->i4_top_ = it->i4_boundary_ + VP8TopLeftI4[0];
+
+ // Import the boundary samples
+ for (i = 0; i < 17; ++i) { // left
+ it->i4_boundary_[i] = it->y_left_[15 - i];
+ }
+ for (i = 0; i < 16; ++i) { // top
+ it->i4_boundary_[17 + i] = it->y_top_[i];
+ }
+ // top-right samples have a special case on the far right of the picture
+ if (it->x_ < enc->mb_w_ - 1) {
+ for (i = 16; i < 16 + 4; ++i) {
+ it->i4_boundary_[17 + i] = it->y_top_[i];
+ }
+ } else { // else, replicate the last valid pixel four times
+ for (i = 16; i < 16 + 4; ++i) {
+ it->i4_boundary_[17 + i] = it->i4_boundary_[17 + 15];
+ }
+ }
+ VP8IteratorNzToBytes(it); // import the non-zero context
+}
+
+int VP8IteratorRotateI4(VP8EncIterator* const it,
+ const uint8_t* const yuv_out) {
+ const uint8_t* const blk = yuv_out + VP8Scan[it->i4_];
+ uint8_t* const top = it->i4_top_;
+ int i;
+
+ // Update the cache with 7 fresh samples
+ for (i = 0; i <= 3; ++i) {
+ top[-4 + i] = blk[i + 3 * BPS]; // store future top samples
+ }
+ if ((it->i4_ & 3) != 3) { // if not on the right sub-blocks #3, #7, #11, #15
+ for (i = 0; i <= 2; ++i) { // store future left samples
+ top[i] = blk[3 + (2 - i) * BPS];
+ }
+ } else { // else replicate top-right samples, as says the specs.
+ for (i = 0; i <= 3; ++i) {
+ top[i] = top[i + 4];
+ }
+ }
+ // move pointers to next sub-block
+ ++it->i4_;
+ if (it->i4_ == 16) { // we're done
+ return 0;
+ }
+
+ it->i4_top_ = it->i4_boundary_ + VP8TopLeftI4[it->i4_];
+ return 1;
+}
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/moz.build b/media/libwebp/src/enc/moz.build
new file mode 100644
index 0000000000..d10abfb032
--- /dev/null
+++ b/media/libwebp/src/enc/moz.build
@@ -0,0 +1,43 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+SOURCES += [
+ 'alpha_enc.c',
+ 'analysis_enc.c',
+ 'backward_references_cost_enc.c',
+ 'backward_references_enc.c',
+ 'config_enc.c',
+ 'cost_enc.c',
+ 'filter_enc.c',
+ 'frame_enc.c',
+ 'histogram_enc.c',
+ 'iterator_enc.c',
+ 'near_lossless_enc.c',
+ 'picture_csp_enc.c',
+ 'picture_enc.c',
+ # 'picture_psnr_enc.c', # Unused file.
+ 'picture_rescale_enc.c',
+ 'picture_tools_enc.c',
+ 'predictor_enc.c',
+ 'quant_enc.c',
+ 'syntax_enc.c',
+ 'token_enc.c',
+ 'tree_enc.c',
+ 'vp8l_enc.c',
+ 'webp_enc.c',
+]
+
+LOCAL_INCLUDES += [
+ '/media/libwebp',
+]
+
+# Add libFuzzer configuration directives
+include('/tools/fuzzing/libfuzzer-config.mozbuild')
+
+FINAL_LIBRARY = 'gkmedias'
+
+# We allow warnings for third-party code that can be updated from upstream.
+AllowCompilerWarnings()
diff --git a/media/libwebp/src/enc/near_lossless_enc.c b/media/libwebp/src/enc/near_lossless_enc.c
new file mode 100644
index 0000000000..5517a7e271
--- /dev/null
+++ b/media/libwebp/src/enc/near_lossless_enc.c
@@ -0,0 +1,151 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Near-lossless image preprocessing adjusts pixel values to help
+// compressibility with a guarantee of maximum deviation between original and
+// resulting pixel values.
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+// Converted to C by Aleksander Kramarz (akramarz@google.com)
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "src/dsp/lossless_common.h"
+#include "src/utils/utils.h"
+#include "src/enc/vp8li_enc.h"
+
+#if (WEBP_NEAR_LOSSLESS == 1)
+
+#define MIN_DIM_FOR_NEAR_LOSSLESS 64
+#define MAX_LIMIT_BITS 5
+
+// Quantizes the value up or down to a multiple of 1<<bits (or to 255),
+// choosing the closer one, resolving ties using bankers' rounding.
+static uint32_t FindClosestDiscretized(uint32_t a, int bits) {
+ const uint32_t mask = (1u << bits) - 1;
+ const uint32_t biased = a + (mask >> 1) + ((a >> bits) & 1);
+ assert(bits > 0);
+ if (biased > 0xff) return 0xff;
+ return biased & ~mask;
+}
+
+// Applies FindClosestDiscretized to all channels of pixel.
+static uint32_t ClosestDiscretizedArgb(uint32_t a, int bits) {
+ return
+ (FindClosestDiscretized(a >> 24, bits) << 24) |
+ (FindClosestDiscretized((a >> 16) & 0xff, bits) << 16) |
+ (FindClosestDiscretized((a >> 8) & 0xff, bits) << 8) |
+ (FindClosestDiscretized(a & 0xff, bits));
+}
+
+// Checks if distance between corresponding channel values of pixels a and b
+// is within the given limit.
+static int IsNear(uint32_t a, uint32_t b, int limit) {
+ int k;
+ for (k = 0; k < 4; ++k) {
+ const int delta =
+ (int)((a >> (k * 8)) & 0xff) - (int)((b >> (k * 8)) & 0xff);
+ if (delta >= limit || delta <= -limit) {
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static int IsSmooth(const uint32_t* const prev_row,
+ const uint32_t* const curr_row,
+ const uint32_t* const next_row,
+ int ix, int limit) {
+ // Check that all pixels in 4-connected neighborhood are smooth.
+ return (IsNear(curr_row[ix], curr_row[ix - 1], limit) &&
+ IsNear(curr_row[ix], curr_row[ix + 1], limit) &&
+ IsNear(curr_row[ix], prev_row[ix], limit) &&
+ IsNear(curr_row[ix], next_row[ix], limit));
+}
+
+// Adjusts pixel values of image with given maximum error.
+static void NearLossless(int xsize, int ysize, const uint32_t* argb_src,
+ int stride, int limit_bits, uint32_t* copy_buffer,
+ uint32_t* argb_dst) {
+ int x, y;
+ const int limit = 1 << limit_bits;
+ uint32_t* prev_row = copy_buffer;
+ uint32_t* curr_row = prev_row + xsize;
+ uint32_t* next_row = curr_row + xsize;
+ memcpy(curr_row, argb_src, xsize * sizeof(argb_src[0]));
+ memcpy(next_row, argb_src + stride, xsize * sizeof(argb_src[0]));
+
+ for (y = 0; y < ysize; ++y, argb_src += stride, argb_dst += xsize) {
+ if (y == 0 || y == ysize - 1) {
+ memcpy(argb_dst, argb_src, xsize * sizeof(argb_src[0]));
+ } else {
+ memcpy(next_row, argb_src + stride, xsize * sizeof(argb_src[0]));
+ argb_dst[0] = argb_src[0];
+ argb_dst[xsize - 1] = argb_src[xsize - 1];
+ for (x = 1; x < xsize - 1; ++x) {
+ if (IsSmooth(prev_row, curr_row, next_row, x, limit)) {
+ argb_dst[x] = curr_row[x];
+ } else {
+ argb_dst[x] = ClosestDiscretizedArgb(curr_row[x], limit_bits);
+ }
+ }
+ }
+ {
+ // Three-way swap.
+ uint32_t* const temp = prev_row;
+ prev_row = curr_row;
+ curr_row = next_row;
+ next_row = temp;
+ }
+ }
+}
+
+int VP8ApplyNearLossless(const WebPPicture* const picture, int quality,
+ uint32_t* const argb_dst) {
+ int i;
+ const int xsize = picture->width;
+ const int ysize = picture->height;
+ const int stride = picture->argb_stride;
+ uint32_t* const copy_buffer =
+ (uint32_t*)WebPSafeMalloc(xsize * 3, sizeof(*copy_buffer));
+ const int limit_bits = VP8LNearLosslessBits(quality);
+ assert(argb_dst != NULL);
+ assert(limit_bits > 0);
+ assert(limit_bits <= MAX_LIMIT_BITS);
+ if (copy_buffer == NULL) {
+ return 0;
+ }
+ // For small icon images, don't attempt to apply near-lossless compression.
+ if ((xsize < MIN_DIM_FOR_NEAR_LOSSLESS &&
+ ysize < MIN_DIM_FOR_NEAR_LOSSLESS) ||
+ ysize < 3) {
+ for (i = 0; i < ysize; ++i) {
+ memcpy(argb_dst + i * xsize, picture->argb + i * picture->argb_stride,
+ xsize * sizeof(*argb_dst));
+ }
+ WebPSafeFree(copy_buffer);
+ return 1;
+ }
+
+ NearLossless(xsize, ysize, picture->argb, stride, limit_bits, copy_buffer,
+ argb_dst);
+ for (i = limit_bits - 1; i != 0; --i) {
+ NearLossless(xsize, ysize, argb_dst, xsize, i, copy_buffer, argb_dst);
+ }
+ WebPSafeFree(copy_buffer);
+ return 1;
+}
+#else // (WEBP_NEAR_LOSSLESS == 1)
+
+// Define a stub to suppress compiler warnings.
+extern void VP8LNearLosslessStub(void);
+void VP8LNearLosslessStub(void) {}
+
+#endif // (WEBP_NEAR_LOSSLESS == 1)
diff --git a/media/libwebp/src/enc/picture_csp_enc.c b/media/libwebp/src/enc/picture_csp_enc.c
new file mode 100644
index 0000000000..78c8ca479b
--- /dev/null
+++ b/media/libwebp/src/enc/picture_csp_enc.c
@@ -0,0 +1,843 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebPPicture utils for colorspace conversion
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+#include <math.h>
+
+#include "sharpyuv/sharpyuv.h"
+#include "sharpyuv/sharpyuv_csp.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/utils/random_utils.h"
+#include "src/utils/utils.h"
+#include "src/dsp/dsp.h"
+#include "src/dsp/lossless.h"
+#include "src/dsp/yuv.h"
+#include "src/dsp/cpu.h"
+
+#if defined(WEBP_USE_THREAD) && !defined(_WIN32)
+#include <pthread.h>
+#endif
+
+// Uncomment to disable gamma-compression during RGB->U/V averaging
+#define USE_GAMMA_COMPRESSION
+
+// If defined, use table to compute x / alpha.
+#define USE_INVERSE_ALPHA_TABLE
+
+#ifdef WORDS_BIGENDIAN
+// uint32_t 0xff000000 is 0xff,00,00,00 in memory
+#define CHANNEL_OFFSET(i) (i)
+#else
+// uint32_t 0xff000000 is 0x00,00,00,ff in memory
+#define CHANNEL_OFFSET(i) (3-(i))
+#endif
+
+#define ALPHA_OFFSET CHANNEL_OFFSET(0)
+
+//------------------------------------------------------------------------------
+// Detection of non-trivial transparency
+
+// Returns true if alpha[] has non-0xff values.
+static int CheckNonOpaque(const uint8_t* alpha, int width, int height,
+ int x_step, int y_step) {
+ if (alpha == NULL) return 0;
+ WebPInitAlphaProcessing();
+ if (x_step == 1) {
+ for (; height-- > 0; alpha += y_step) {
+ if (WebPHasAlpha8b(alpha, width)) return 1;
+ }
+ } else {
+ for (; height-- > 0; alpha += y_step) {
+ if (WebPHasAlpha32b(alpha, width)) return 1;
+ }
+ }
+ return 0;
+}
+
+// Checking for the presence of non-opaque alpha.
+int WebPPictureHasTransparency(const WebPPicture* picture) {
+ if (picture == NULL) return 0;
+ if (picture->use_argb) {
+ if (picture->argb != NULL) {
+ return CheckNonOpaque((const uint8_t*)picture->argb + ALPHA_OFFSET,
+ picture->width, picture->height,
+ 4, picture->argb_stride * sizeof(*picture->argb));
+ }
+ return 0;
+ }
+ return CheckNonOpaque(picture->a, picture->width, picture->height,
+ 1, picture->a_stride);
+}
+
+//------------------------------------------------------------------------------
+// Code for gamma correction
+
+#if defined(USE_GAMMA_COMPRESSION)
+
+// Gamma correction compensates loss of resolution during chroma subsampling.
+#define GAMMA_FIX 12 // fixed-point precision for linear values
+#define GAMMA_TAB_FIX 7 // fixed-point fractional bits precision
+#define GAMMA_TAB_SIZE (1 << (GAMMA_FIX - GAMMA_TAB_FIX))
+static const double kGamma = 0.80;
+static const int kGammaScale = ((1 << GAMMA_FIX) - 1);
+static const int kGammaTabScale = (1 << GAMMA_TAB_FIX);
+static const int kGammaTabRounder = (1 << GAMMA_TAB_FIX >> 1);
+
+static int kLinearToGammaTab[GAMMA_TAB_SIZE + 1];
+static uint16_t kGammaToLinearTab[256];
+static volatile int kGammaTablesOk = 0;
+static void InitGammaTables(void);
+
+WEBP_DSP_INIT_FUNC(InitGammaTables) {
+ if (!kGammaTablesOk) {
+ int v;
+ const double scale = (double)(1 << GAMMA_TAB_FIX) / kGammaScale;
+ const double norm = 1. / 255.;
+ for (v = 0; v <= 255; ++v) {
+ kGammaToLinearTab[v] =
+ (uint16_t)(pow(norm * v, kGamma) * kGammaScale + .5);
+ }
+ for (v = 0; v <= GAMMA_TAB_SIZE; ++v) {
+ kLinearToGammaTab[v] = (int)(255. * pow(scale * v, 1. / kGamma) + .5);
+ }
+ kGammaTablesOk = 1;
+ }
+}
+
+static WEBP_INLINE uint32_t GammaToLinear(uint8_t v) {
+ return kGammaToLinearTab[v];
+}
+
+static WEBP_INLINE int Interpolate(int v) {
+ const int tab_pos = v >> (GAMMA_TAB_FIX + 2); // integer part
+ const int x = v & ((kGammaTabScale << 2) - 1); // fractional part
+ const int v0 = kLinearToGammaTab[tab_pos];
+ const int v1 = kLinearToGammaTab[tab_pos + 1];
+ const int y = v1 * x + v0 * ((kGammaTabScale << 2) - x); // interpolate
+ assert(tab_pos + 1 < GAMMA_TAB_SIZE + 1);
+ return y;
+}
+
+// Convert a linear value 'v' to YUV_FIX+2 fixed-point precision
+// U/V value, suitable for RGBToU/V calls.
+static WEBP_INLINE int LinearToGamma(uint32_t base_value, int shift) {
+ const int y = Interpolate(base_value << shift); // final uplifted value
+ return (y + kGammaTabRounder) >> GAMMA_TAB_FIX; // descale
+}
+
+#else
+
+static void InitGammaTables(void) {}
+static WEBP_INLINE uint32_t GammaToLinear(uint8_t v) { return v; }
+static WEBP_INLINE int LinearToGamma(uint32_t base_value, int shift) {
+ return (int)(base_value << shift);
+}
+
+#endif // USE_GAMMA_COMPRESSION
+
+//------------------------------------------------------------------------------
+// RGB -> YUV conversion
+
+static int RGBToY(int r, int g, int b, VP8Random* const rg) {
+ return (rg == NULL) ? VP8RGBToY(r, g, b, YUV_HALF)
+ : VP8RGBToY(r, g, b, VP8RandomBits(rg, YUV_FIX));
+}
+
+static int RGBToU(int r, int g, int b, VP8Random* const rg) {
+ return (rg == NULL) ? VP8RGBToU(r, g, b, YUV_HALF << 2)
+ : VP8RGBToU(r, g, b, VP8RandomBits(rg, YUV_FIX + 2));
+}
+
+static int RGBToV(int r, int g, int b, VP8Random* const rg) {
+ return (rg == NULL) ? VP8RGBToV(r, g, b, YUV_HALF << 2)
+ : VP8RGBToV(r, g, b, VP8RandomBits(rg, YUV_FIX + 2));
+}
+
+//------------------------------------------------------------------------------
+// Sharp RGB->YUV conversion
+
+static const int kMinDimensionIterativeConversion = 4;
+
+//------------------------------------------------------------------------------
+// Main function
+
+static int PreprocessARGB(const uint8_t* r_ptr,
+ const uint8_t* g_ptr,
+ const uint8_t* b_ptr,
+ int step, int rgb_stride,
+ WebPPicture* const picture) {
+ const int ok = SharpYuvConvert(
+ r_ptr, g_ptr, b_ptr, step, rgb_stride, /*rgb_bit_depth=*/8,
+ picture->y, picture->y_stride, picture->u, picture->uv_stride, picture->v,
+ picture->uv_stride, /*yuv_bit_depth=*/8, picture->width,
+ picture->height, SharpYuvGetConversionMatrix(kSharpYuvMatrixWebp));
+ if (!ok) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ return ok;
+}
+
+//------------------------------------------------------------------------------
+// "Fast" regular RGB->YUV
+
+#define SUM4(ptr, step) LinearToGamma( \
+ GammaToLinear((ptr)[0]) + \
+ GammaToLinear((ptr)[(step)]) + \
+ GammaToLinear((ptr)[rgb_stride]) + \
+ GammaToLinear((ptr)[rgb_stride + (step)]), 0) \
+
+#define SUM2(ptr) \
+ LinearToGamma(GammaToLinear((ptr)[0]) + GammaToLinear((ptr)[rgb_stride]), 1)
+
+#define SUM2ALPHA(ptr) ((ptr)[0] + (ptr)[rgb_stride])
+#define SUM4ALPHA(ptr) (SUM2ALPHA(ptr) + SUM2ALPHA((ptr) + 4))
+
+#if defined(USE_INVERSE_ALPHA_TABLE)
+
+static const int kAlphaFix = 19;
+// Following table is (1 << kAlphaFix) / a. The (v * kInvAlpha[a]) >> kAlphaFix
+// formula is then equal to v / a in most (99.6%) cases. Note that this table
+// and constant are adjusted very tightly to fit 32b arithmetic.
+// In particular, they use the fact that the operands for 'v / a' are actually
+// derived as v = (a0.p0 + a1.p1 + a2.p2 + a3.p3) and a = a0 + a1 + a2 + a3
+// with ai in [0..255] and pi in [0..1<<GAMMA_FIX). The constraint to avoid
+// overflow is: GAMMA_FIX + kAlphaFix <= 31.
+static const uint32_t kInvAlpha[4 * 0xff + 1] = {
+ 0, /* alpha = 0 */
+ 524288, 262144, 174762, 131072, 104857, 87381, 74898, 65536,
+ 58254, 52428, 47662, 43690, 40329, 37449, 34952, 32768,
+ 30840, 29127, 27594, 26214, 24966, 23831, 22795, 21845,
+ 20971, 20164, 19418, 18724, 18078, 17476, 16912, 16384,
+ 15887, 15420, 14979, 14563, 14169, 13797, 13443, 13107,
+ 12787, 12483, 12192, 11915, 11650, 11397, 11155, 10922,
+ 10699, 10485, 10280, 10082, 9892, 9709, 9532, 9362,
+ 9198, 9039, 8886, 8738, 8594, 8456, 8322, 8192,
+ 8065, 7943, 7825, 7710, 7598, 7489, 7384, 7281,
+ 7182, 7084, 6990, 6898, 6808, 6721, 6636, 6553,
+ 6472, 6393, 6316, 6241, 6168, 6096, 6026, 5957,
+ 5890, 5825, 5761, 5698, 5637, 5577, 5518, 5461,
+ 5405, 5349, 5295, 5242, 5190, 5140, 5090, 5041,
+ 4993, 4946, 4899, 4854, 4809, 4766, 4723, 4681,
+ 4639, 4599, 4559, 4519, 4481, 4443, 4405, 4369,
+ 4332, 4297, 4262, 4228, 4194, 4161, 4128, 4096,
+ 4064, 4032, 4002, 3971, 3942, 3912, 3883, 3855,
+ 3826, 3799, 3771, 3744, 3718, 3692, 3666, 3640,
+ 3615, 3591, 3566, 3542, 3518, 3495, 3472, 3449,
+ 3426, 3404, 3382, 3360, 3339, 3318, 3297, 3276,
+ 3256, 3236, 3216, 3196, 3177, 3158, 3139, 3120,
+ 3102, 3084, 3066, 3048, 3030, 3013, 2995, 2978,
+ 2962, 2945, 2928, 2912, 2896, 2880, 2864, 2849,
+ 2833, 2818, 2803, 2788, 2774, 2759, 2744, 2730,
+ 2716, 2702, 2688, 2674, 2661, 2647, 2634, 2621,
+ 2608, 2595, 2582, 2570, 2557, 2545, 2532, 2520,
+ 2508, 2496, 2484, 2473, 2461, 2449, 2438, 2427,
+ 2416, 2404, 2394, 2383, 2372, 2361, 2351, 2340,
+ 2330, 2319, 2309, 2299, 2289, 2279, 2269, 2259,
+ 2250, 2240, 2231, 2221, 2212, 2202, 2193, 2184,
+ 2175, 2166, 2157, 2148, 2139, 2131, 2122, 2114,
+ 2105, 2097, 2088, 2080, 2072, 2064, 2056, 2048,
+ 2040, 2032, 2024, 2016, 2008, 2001, 1993, 1985,
+ 1978, 1971, 1963, 1956, 1949, 1941, 1934, 1927,
+ 1920, 1913, 1906, 1899, 1892, 1885, 1879, 1872,
+ 1865, 1859, 1852, 1846, 1839, 1833, 1826, 1820,
+ 1814, 1807, 1801, 1795, 1789, 1783, 1777, 1771,
+ 1765, 1759, 1753, 1747, 1741, 1736, 1730, 1724,
+ 1718, 1713, 1707, 1702, 1696, 1691, 1685, 1680,
+ 1675, 1669, 1664, 1659, 1653, 1648, 1643, 1638,
+ 1633, 1628, 1623, 1618, 1613, 1608, 1603, 1598,
+ 1593, 1588, 1583, 1579, 1574, 1569, 1565, 1560,
+ 1555, 1551, 1546, 1542, 1537, 1533, 1528, 1524,
+ 1519, 1515, 1510, 1506, 1502, 1497, 1493, 1489,
+ 1485, 1481, 1476, 1472, 1468, 1464, 1460, 1456,
+ 1452, 1448, 1444, 1440, 1436, 1432, 1428, 1424,
+ 1420, 1416, 1413, 1409, 1405, 1401, 1398, 1394,
+ 1390, 1387, 1383, 1379, 1376, 1372, 1368, 1365,
+ 1361, 1358, 1354, 1351, 1347, 1344, 1340, 1337,
+ 1334, 1330, 1327, 1323, 1320, 1317, 1314, 1310,
+ 1307, 1304, 1300, 1297, 1294, 1291, 1288, 1285,
+ 1281, 1278, 1275, 1272, 1269, 1266, 1263, 1260,
+ 1257, 1254, 1251, 1248, 1245, 1242, 1239, 1236,
+ 1233, 1230, 1227, 1224, 1222, 1219, 1216, 1213,
+ 1210, 1208, 1205, 1202, 1199, 1197, 1194, 1191,
+ 1188, 1186, 1183, 1180, 1178, 1175, 1172, 1170,
+ 1167, 1165, 1162, 1159, 1157, 1154, 1152, 1149,
+ 1147, 1144, 1142, 1139, 1137, 1134, 1132, 1129,
+ 1127, 1125, 1122, 1120, 1117, 1115, 1113, 1110,
+ 1108, 1106, 1103, 1101, 1099, 1096, 1094, 1092,
+ 1089, 1087, 1085, 1083, 1081, 1078, 1076, 1074,
+ 1072, 1069, 1067, 1065, 1063, 1061, 1059, 1057,
+ 1054, 1052, 1050, 1048, 1046, 1044, 1042, 1040,
+ 1038, 1036, 1034, 1032, 1030, 1028, 1026, 1024,
+ 1022, 1020, 1018, 1016, 1014, 1012, 1010, 1008,
+ 1006, 1004, 1002, 1000, 998, 996, 994, 992,
+ 991, 989, 987, 985, 983, 981, 979, 978,
+ 976, 974, 972, 970, 969, 967, 965, 963,
+ 961, 960, 958, 956, 954, 953, 951, 949,
+ 948, 946, 944, 942, 941, 939, 937, 936,
+ 934, 932, 931, 929, 927, 926, 924, 923,
+ 921, 919, 918, 916, 914, 913, 911, 910,
+ 908, 907, 905, 903, 902, 900, 899, 897,
+ 896, 894, 893, 891, 890, 888, 887, 885,
+ 884, 882, 881, 879, 878, 876, 875, 873,
+ 872, 870, 869, 868, 866, 865, 863, 862,
+ 860, 859, 858, 856, 855, 853, 852, 851,
+ 849, 848, 846, 845, 844, 842, 841, 840,
+ 838, 837, 836, 834, 833, 832, 830, 829,
+ 828, 826, 825, 824, 823, 821, 820, 819,
+ 817, 816, 815, 814, 812, 811, 810, 809,
+ 807, 806, 805, 804, 802, 801, 800, 799,
+ 798, 796, 795, 794, 793, 791, 790, 789,
+ 788, 787, 786, 784, 783, 782, 781, 780,
+ 779, 777, 776, 775, 774, 773, 772, 771,
+ 769, 768, 767, 766, 765, 764, 763, 762,
+ 760, 759, 758, 757, 756, 755, 754, 753,
+ 752, 751, 750, 748, 747, 746, 745, 744,
+ 743, 742, 741, 740, 739, 738, 737, 736,
+ 735, 734, 733, 732, 731, 730, 729, 728,
+ 727, 726, 725, 724, 723, 722, 721, 720,
+ 719, 718, 717, 716, 715, 714, 713, 712,
+ 711, 710, 709, 708, 707, 706, 705, 704,
+ 703, 702, 701, 700, 699, 699, 698, 697,
+ 696, 695, 694, 693, 692, 691, 690, 689,
+ 688, 688, 687, 686, 685, 684, 683, 682,
+ 681, 680, 680, 679, 678, 677, 676, 675,
+ 674, 673, 673, 672, 671, 670, 669, 668,
+ 667, 667, 666, 665, 664, 663, 662, 661,
+ 661, 660, 659, 658, 657, 657, 656, 655,
+ 654, 653, 652, 652, 651, 650, 649, 648,
+ 648, 647, 646, 645, 644, 644, 643, 642,
+ 641, 640, 640, 639, 638, 637, 637, 636,
+ 635, 634, 633, 633, 632, 631, 630, 630,
+ 629, 628, 627, 627, 626, 625, 624, 624,
+ 623, 622, 621, 621, 620, 619, 618, 618,
+ 617, 616, 616, 615, 614, 613, 613, 612,
+ 611, 611, 610, 609, 608, 608, 607, 606,
+ 606, 605, 604, 604, 603, 602, 601, 601,
+ 600, 599, 599, 598, 597, 597, 596, 595,
+ 595, 594, 593, 593, 592, 591, 591, 590,
+ 589, 589, 588, 587, 587, 586, 585, 585,
+ 584, 583, 583, 582, 581, 581, 580, 579,
+ 579, 578, 578, 577, 576, 576, 575, 574,
+ 574, 573, 572, 572, 571, 571, 570, 569,
+ 569, 568, 568, 567, 566, 566, 565, 564,
+ 564, 563, 563, 562, 561, 561, 560, 560,
+ 559, 558, 558, 557, 557, 556, 555, 555,
+ 554, 554, 553, 553, 552, 551, 551, 550,
+ 550, 549, 548, 548, 547, 547, 546, 546,
+ 545, 544, 544, 543, 543, 542, 542, 541,
+ 541, 540, 539, 539, 538, 538, 537, 537,
+ 536, 536, 535, 534, 534, 533, 533, 532,
+ 532, 531, 531, 530, 530, 529, 529, 528,
+ 527, 527, 526, 526, 525, 525, 524, 524,
+ 523, 523, 522, 522, 521, 521, 520, 520,
+ 519, 519, 518, 518, 517, 517, 516, 516,
+ 515, 515, 514, 514
+};
+
+// Note that LinearToGamma() expects the values to be premultiplied by 4,
+// so we incorporate this factor 4 inside the DIVIDE_BY_ALPHA macro directly.
+#define DIVIDE_BY_ALPHA(sum, a) (((sum) * kInvAlpha[(a)]) >> (kAlphaFix - 2))
+
+#else
+
+#define DIVIDE_BY_ALPHA(sum, a) (4 * (sum) / (a))
+
+#endif // USE_INVERSE_ALPHA_TABLE
+
+static WEBP_INLINE int LinearToGammaWeighted(const uint8_t* src,
+ const uint8_t* a_ptr,
+ uint32_t total_a, int step,
+ int rgb_stride) {
+ const uint32_t sum =
+ a_ptr[0] * GammaToLinear(src[0]) +
+ a_ptr[step] * GammaToLinear(src[step]) +
+ a_ptr[rgb_stride] * GammaToLinear(src[rgb_stride]) +
+ a_ptr[rgb_stride + step] * GammaToLinear(src[rgb_stride + step]);
+ assert(total_a > 0 && total_a <= 4 * 0xff);
+#if defined(USE_INVERSE_ALPHA_TABLE)
+ assert((uint64_t)sum * kInvAlpha[total_a] < ((uint64_t)1 << 32));
+#endif
+ return LinearToGamma(DIVIDE_BY_ALPHA(sum, total_a), 0);
+}
+
+static WEBP_INLINE void ConvertRowToY(const uint8_t* const r_ptr,
+ const uint8_t* const g_ptr,
+ const uint8_t* const b_ptr,
+ int step,
+ uint8_t* const dst_y,
+ int width,
+ VP8Random* const rg) {
+ int i, j;
+ for (i = 0, j = 0; i < width; i += 1, j += step) {
+ dst_y[i] = RGBToY(r_ptr[j], g_ptr[j], b_ptr[j], rg);
+ }
+}
+
+static WEBP_INLINE void AccumulateRGBA(const uint8_t* const r_ptr,
+ const uint8_t* const g_ptr,
+ const uint8_t* const b_ptr,
+ const uint8_t* const a_ptr,
+ int rgb_stride,
+ uint16_t* dst, int width) {
+ int i, j;
+ // we loop over 2x2 blocks and produce one R/G/B/A value for each.
+ for (i = 0, j = 0; i < (width >> 1); i += 1, j += 2 * 4, dst += 4) {
+ const uint32_t a = SUM4ALPHA(a_ptr + j);
+ int r, g, b;
+ if (a == 4 * 0xff || a == 0) {
+ r = SUM4(r_ptr + j, 4);
+ g = SUM4(g_ptr + j, 4);
+ b = SUM4(b_ptr + j, 4);
+ } else {
+ r = LinearToGammaWeighted(r_ptr + j, a_ptr + j, a, 4, rgb_stride);
+ g = LinearToGammaWeighted(g_ptr + j, a_ptr + j, a, 4, rgb_stride);
+ b = LinearToGammaWeighted(b_ptr + j, a_ptr + j, a, 4, rgb_stride);
+ }
+ dst[0] = r;
+ dst[1] = g;
+ dst[2] = b;
+ dst[3] = a;
+ }
+ if (width & 1) {
+ const uint32_t a = 2u * SUM2ALPHA(a_ptr + j);
+ int r, g, b;
+ if (a == 4 * 0xff || a == 0) {
+ r = SUM2(r_ptr + j);
+ g = SUM2(g_ptr + j);
+ b = SUM2(b_ptr + j);
+ } else {
+ r = LinearToGammaWeighted(r_ptr + j, a_ptr + j, a, 0, rgb_stride);
+ g = LinearToGammaWeighted(g_ptr + j, a_ptr + j, a, 0, rgb_stride);
+ b = LinearToGammaWeighted(b_ptr + j, a_ptr + j, a, 0, rgb_stride);
+ }
+ dst[0] = r;
+ dst[1] = g;
+ dst[2] = b;
+ dst[3] = a;
+ }
+}
+
+static WEBP_INLINE void AccumulateRGB(const uint8_t* const r_ptr,
+ const uint8_t* const g_ptr,
+ const uint8_t* const b_ptr,
+ int step, int rgb_stride,
+ uint16_t* dst, int width) {
+ int i, j;
+ for (i = 0, j = 0; i < (width >> 1); i += 1, j += 2 * step, dst += 4) {
+ dst[0] = SUM4(r_ptr + j, step);
+ dst[1] = SUM4(g_ptr + j, step);
+ dst[2] = SUM4(b_ptr + j, step);
+ // MemorySanitizer may raise false positives with data that passes through
+ // RGBA32PackedToPlanar_16b_SSE41() due to incorrect modeling of shuffles.
+ // See https://crbug.com/webp/573.
+#ifdef WEBP_MSAN
+ dst[3] = 0;
+#endif
+ }
+ if (width & 1) {
+ dst[0] = SUM2(r_ptr + j);
+ dst[1] = SUM2(g_ptr + j);
+ dst[2] = SUM2(b_ptr + j);
+#ifdef WEBP_MSAN
+ dst[3] = 0;
+#endif
+ }
+}
+
+static WEBP_INLINE void ConvertRowsToUV(const uint16_t* rgb,
+ uint8_t* const dst_u,
+ uint8_t* const dst_v,
+ int width,
+ VP8Random* const rg) {
+ int i;
+ for (i = 0; i < width; i += 1, rgb += 4) {
+ const int r = rgb[0], g = rgb[1], b = rgb[2];
+ dst_u[i] = RGBToU(r, g, b, rg);
+ dst_v[i] = RGBToV(r, g, b, rg);
+ }
+}
+
+extern void SharpYuvInit(VP8CPUInfo cpu_info_func);
+
+static int ImportYUVAFromRGBA(const uint8_t* r_ptr,
+ const uint8_t* g_ptr,
+ const uint8_t* b_ptr,
+ const uint8_t* a_ptr,
+ int step, // bytes per pixel
+ int rgb_stride, // bytes per scanline
+ float dithering,
+ int use_iterative_conversion,
+ WebPPicture* const picture) {
+ int y;
+ const int width = picture->width;
+ const int height = picture->height;
+ const int has_alpha = CheckNonOpaque(a_ptr, width, height, step, rgb_stride);
+ const int is_rgb = (r_ptr < b_ptr); // otherwise it's bgr
+
+ picture->colorspace = has_alpha ? WEBP_YUV420A : WEBP_YUV420;
+ picture->use_argb = 0;
+
+ // disable smart conversion if source is too small (overkill).
+ if (width < kMinDimensionIterativeConversion ||
+ height < kMinDimensionIterativeConversion) {
+ use_iterative_conversion = 0;
+ }
+
+ if (!WebPPictureAllocYUVA(picture)) {
+ return 0;
+ }
+ if (has_alpha) {
+ assert(step == 4);
+#if defined(USE_GAMMA_COMPRESSION) && defined(USE_INVERSE_ALPHA_TABLE)
+ assert(kAlphaFix + GAMMA_FIX <= 31);
+#endif
+ }
+
+ if (use_iterative_conversion) {
+ SharpYuvInit(VP8GetCPUInfo);
+ if (!PreprocessARGB(r_ptr, g_ptr, b_ptr, step, rgb_stride, picture)) {
+ return 0;
+ }
+ if (has_alpha) {
+ WebPExtractAlpha(a_ptr, rgb_stride, width, height,
+ picture->a, picture->a_stride);
+ }
+ } else {
+ const int uv_width = (width + 1) >> 1;
+ int use_dsp = (step == 3); // use special function in this case
+ // temporary storage for accumulated R/G/B values during conversion to U/V
+ uint16_t* const tmp_rgb =
+ (uint16_t*)WebPSafeMalloc(4 * uv_width, sizeof(*tmp_rgb));
+ uint8_t* dst_y = picture->y;
+ uint8_t* dst_u = picture->u;
+ uint8_t* dst_v = picture->v;
+ uint8_t* dst_a = picture->a;
+
+ VP8Random base_rg;
+ VP8Random* rg = NULL;
+ if (dithering > 0.) {
+ VP8InitRandom(&base_rg, dithering);
+ rg = &base_rg;
+ use_dsp = 0; // can't use dsp in this case
+ }
+ WebPInitConvertARGBToYUV();
+ InitGammaTables();
+
+ if (tmp_rgb == NULL) return 0; // malloc error
+
+ // Downsample Y/U/V planes, two rows at a time
+ for (y = 0; y < (height >> 1); ++y) {
+ int rows_have_alpha = has_alpha;
+ if (use_dsp) {
+ if (is_rgb) {
+ WebPConvertRGB24ToY(r_ptr, dst_y, width);
+ WebPConvertRGB24ToY(r_ptr + rgb_stride,
+ dst_y + picture->y_stride, width);
+ } else {
+ WebPConvertBGR24ToY(b_ptr, dst_y, width);
+ WebPConvertBGR24ToY(b_ptr + rgb_stride,
+ dst_y + picture->y_stride, width);
+ }
+ } else {
+ ConvertRowToY(r_ptr, g_ptr, b_ptr, step, dst_y, width, rg);
+ ConvertRowToY(r_ptr + rgb_stride,
+ g_ptr + rgb_stride,
+ b_ptr + rgb_stride, step,
+ dst_y + picture->y_stride, width, rg);
+ }
+ dst_y += 2 * picture->y_stride;
+ if (has_alpha) {
+ rows_have_alpha &= !WebPExtractAlpha(a_ptr, rgb_stride, width, 2,
+ dst_a, picture->a_stride);
+ dst_a += 2 * picture->a_stride;
+ }
+ // Collect averaged R/G/B(/A)
+ if (!rows_have_alpha) {
+ AccumulateRGB(r_ptr, g_ptr, b_ptr, step, rgb_stride, tmp_rgb, width);
+ } else {
+ AccumulateRGBA(r_ptr, g_ptr, b_ptr, a_ptr, rgb_stride, tmp_rgb, width);
+ }
+ // Convert to U/V
+ if (rg == NULL) {
+ WebPConvertRGBA32ToUV(tmp_rgb, dst_u, dst_v, uv_width);
+ } else {
+ ConvertRowsToUV(tmp_rgb, dst_u, dst_v, uv_width, rg);
+ }
+ dst_u += picture->uv_stride;
+ dst_v += picture->uv_stride;
+ r_ptr += 2 * rgb_stride;
+ b_ptr += 2 * rgb_stride;
+ g_ptr += 2 * rgb_stride;
+ if (has_alpha) a_ptr += 2 * rgb_stride;
+ }
+ if (height & 1) { // extra last row
+ int row_has_alpha = has_alpha;
+ if (use_dsp) {
+ if (r_ptr < b_ptr) {
+ WebPConvertRGB24ToY(r_ptr, dst_y, width);
+ } else {
+ WebPConvertBGR24ToY(b_ptr, dst_y, width);
+ }
+ } else {
+ ConvertRowToY(r_ptr, g_ptr, b_ptr, step, dst_y, width, rg);
+ }
+ if (row_has_alpha) {
+ row_has_alpha &= !WebPExtractAlpha(a_ptr, 0, width, 1, dst_a, 0);
+ }
+ // Collect averaged R/G/B(/A)
+ if (!row_has_alpha) {
+ // Collect averaged R/G/B
+ AccumulateRGB(r_ptr, g_ptr, b_ptr, step, /* rgb_stride = */ 0,
+ tmp_rgb, width);
+ } else {
+ AccumulateRGBA(r_ptr, g_ptr, b_ptr, a_ptr, /* rgb_stride = */ 0,
+ tmp_rgb, width);
+ }
+ if (rg == NULL) {
+ WebPConvertRGBA32ToUV(tmp_rgb, dst_u, dst_v, uv_width);
+ } else {
+ ConvertRowsToUV(tmp_rgb, dst_u, dst_v, uv_width, rg);
+ }
+ }
+ WebPSafeFree(tmp_rgb);
+ }
+ return 1;
+}
+
+#undef SUM4
+#undef SUM2
+#undef SUM4ALPHA
+#undef SUM2ALPHA
+
+//------------------------------------------------------------------------------
+// call for ARGB->YUVA conversion
+
+static int PictureARGBToYUVA(WebPPicture* picture, WebPEncCSP colorspace,
+ float dithering, int use_iterative_conversion) {
+ if (picture == NULL) return 0;
+ if (picture->argb == NULL) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER);
+ } else if ((colorspace & WEBP_CSP_UV_MASK) != WEBP_YUV420) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION);
+ } else {
+ const uint8_t* const argb = (const uint8_t*)picture->argb;
+ const uint8_t* const a = argb + CHANNEL_OFFSET(0);
+ const uint8_t* const r = argb + CHANNEL_OFFSET(1);
+ const uint8_t* const g = argb + CHANNEL_OFFSET(2);
+ const uint8_t* const b = argb + CHANNEL_OFFSET(3);
+
+ picture->colorspace = WEBP_YUV420;
+ return ImportYUVAFromRGBA(r, g, b, a, 4, 4 * picture->argb_stride,
+ dithering, use_iterative_conversion, picture);
+ }
+}
+
+int WebPPictureARGBToYUVADithered(WebPPicture* picture, WebPEncCSP colorspace,
+ float dithering) {
+ return PictureARGBToYUVA(picture, colorspace, dithering, 0);
+}
+
+int WebPPictureARGBToYUVA(WebPPicture* picture, WebPEncCSP colorspace) {
+ return PictureARGBToYUVA(picture, colorspace, 0.f, 0);
+}
+
+int WebPPictureSharpARGBToYUVA(WebPPicture* picture) {
+ return PictureARGBToYUVA(picture, WEBP_YUV420, 0.f, 1);
+}
+// for backward compatibility
+int WebPPictureSmartARGBToYUVA(WebPPicture* picture) {
+ return WebPPictureSharpARGBToYUVA(picture);
+}
+
+//------------------------------------------------------------------------------
+// call for YUVA -> ARGB conversion
+
+int WebPPictureYUVAToARGB(WebPPicture* picture) {
+ if (picture == NULL) return 0;
+ if (picture->y == NULL || picture->u == NULL || picture->v == NULL) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER);
+ }
+ if ((picture->colorspace & WEBP_CSP_ALPHA_BIT) && picture->a == NULL) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER);
+ }
+ if ((picture->colorspace & WEBP_CSP_UV_MASK) != WEBP_YUV420) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION);
+ }
+ // Allocate a new argb buffer (discarding the previous one).
+ if (!WebPPictureAllocARGB(picture)) return 0;
+ picture->use_argb = 1;
+
+ // Convert
+ {
+ int y;
+ const int width = picture->width;
+ const int height = picture->height;
+ const int argb_stride = 4 * picture->argb_stride;
+ uint8_t* dst = (uint8_t*)picture->argb;
+ const uint8_t* cur_u = picture->u, *cur_v = picture->v, *cur_y = picture->y;
+ WebPUpsampleLinePairFunc upsample =
+ WebPGetLinePairConverter(ALPHA_OFFSET > 0);
+
+ // First row, with replicated top samples.
+ upsample(cur_y, NULL, cur_u, cur_v, cur_u, cur_v, dst, NULL, width);
+ cur_y += picture->y_stride;
+ dst += argb_stride;
+ // Center rows.
+ for (y = 1; y + 1 < height; y += 2) {
+ const uint8_t* const top_u = cur_u;
+ const uint8_t* const top_v = cur_v;
+ cur_u += picture->uv_stride;
+ cur_v += picture->uv_stride;
+ upsample(cur_y, cur_y + picture->y_stride, top_u, top_v, cur_u, cur_v,
+ dst, dst + argb_stride, width);
+ cur_y += 2 * picture->y_stride;
+ dst += 2 * argb_stride;
+ }
+ // Last row (if needed), with replicated bottom samples.
+ if (height > 1 && !(height & 1)) {
+ upsample(cur_y, NULL, cur_u, cur_v, cur_u, cur_v, dst, NULL, width);
+ }
+ // Insert alpha values if needed, in replacement for the default 0xff ones.
+ if (picture->colorspace & WEBP_CSP_ALPHA_BIT) {
+ for (y = 0; y < height; ++y) {
+ uint32_t* const argb_dst = picture->argb + y * picture->argb_stride;
+ const uint8_t* const src = picture->a + y * picture->a_stride;
+ int x;
+ for (x = 0; x < width; ++x) {
+ argb_dst[x] = (argb_dst[x] & 0x00ffffffu) | ((uint32_t)src[x] << 24);
+ }
+ }
+ }
+ }
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+// automatic import / conversion
+
+static int Import(WebPPicture* const picture,
+ const uint8_t* rgb, int rgb_stride,
+ int step, int swap_rb, int import_alpha) {
+ int y;
+ // swap_rb -> b,g,r,a , !swap_rb -> r,g,b,a
+ const uint8_t* r_ptr = rgb + (swap_rb ? 2 : 0);
+ const uint8_t* g_ptr = rgb + 1;
+ const uint8_t* b_ptr = rgb + (swap_rb ? 0 : 2);
+ const int width = picture->width;
+ const int height = picture->height;
+
+ if (abs(rgb_stride) < (import_alpha ? 4 : 3) * width) return 0;
+
+ if (!picture->use_argb) {
+ const uint8_t* a_ptr = import_alpha ? rgb + 3 : NULL;
+ return ImportYUVAFromRGBA(r_ptr, g_ptr, b_ptr, a_ptr, step, rgb_stride,
+ 0.f /* no dithering */, 0, picture);
+ }
+ if (!WebPPictureAlloc(picture)) return 0;
+
+ VP8LDspInit();
+ WebPInitAlphaProcessing();
+
+ if (import_alpha) {
+ // dst[] byte order is {a,r,g,b} for big-endian, {b,g,r,a} for little endian
+ uint32_t* dst = picture->argb;
+ const int do_copy = (ALPHA_OFFSET == 3) && swap_rb;
+ assert(step == 4);
+ if (do_copy) {
+ for (y = 0; y < height; ++y) {
+ memcpy(dst, rgb, width * 4);
+ rgb += rgb_stride;
+ dst += picture->argb_stride;
+ }
+ } else {
+ for (y = 0; y < height; ++y) {
+#ifdef WORDS_BIGENDIAN
+ // BGRA or RGBA input order.
+ const uint8_t* a_ptr = rgb + 3;
+ WebPPackARGB(a_ptr, r_ptr, g_ptr, b_ptr, width, dst);
+ r_ptr += rgb_stride;
+ g_ptr += rgb_stride;
+ b_ptr += rgb_stride;
+#else
+ // RGBA input order. Need to swap R and B.
+ VP8LConvertBGRAToRGBA((const uint32_t*)rgb, width, (uint8_t*)dst);
+#endif
+ rgb += rgb_stride;
+ dst += picture->argb_stride;
+ }
+ }
+ } else {
+ uint32_t* dst = picture->argb;
+ assert(step >= 3);
+ for (y = 0; y < height; ++y) {
+ WebPPackRGB(r_ptr, g_ptr, b_ptr, width, step, dst);
+ r_ptr += rgb_stride;
+ g_ptr += rgb_stride;
+ b_ptr += rgb_stride;
+ dst += picture->argb_stride;
+ }
+ }
+ return 1;
+}
+
+// Public API
+
+#if !defined(WEBP_REDUCE_CSP)
+
+int WebPPictureImportBGR(WebPPicture* picture,
+ const uint8_t* bgr, int bgr_stride) {
+ return (picture != NULL && bgr != NULL)
+ ? Import(picture, bgr, bgr_stride, 3, 1, 0)
+ : 0;
+}
+
+int WebPPictureImportBGRA(WebPPicture* picture,
+ const uint8_t* bgra, int bgra_stride) {
+ return (picture != NULL && bgra != NULL)
+ ? Import(picture, bgra, bgra_stride, 4, 1, 1)
+ : 0;
+}
+
+
+int WebPPictureImportBGRX(WebPPicture* picture,
+ const uint8_t* bgrx, int bgrx_stride) {
+ return (picture != NULL && bgrx != NULL)
+ ? Import(picture, bgrx, bgrx_stride, 4, 1, 0)
+ : 0;
+}
+
+#endif // WEBP_REDUCE_CSP
+
+int WebPPictureImportRGB(WebPPicture* picture,
+ const uint8_t* rgb, int rgb_stride) {
+ return (picture != NULL && rgb != NULL)
+ ? Import(picture, rgb, rgb_stride, 3, 0, 0)
+ : 0;
+}
+
+int WebPPictureImportRGBA(WebPPicture* picture,
+ const uint8_t* rgba, int rgba_stride) {
+ return (picture != NULL && rgba != NULL)
+ ? Import(picture, rgba, rgba_stride, 4, 0, 1)
+ : 0;
+}
+
+int WebPPictureImportRGBX(WebPPicture* picture,
+ const uint8_t* rgbx, int rgbx_stride) {
+ return (picture != NULL && rgbx != NULL)
+ ? Import(picture, rgbx, rgbx_stride, 4, 0, 0)
+ : 0;
+}
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/picture_enc.c b/media/libwebp/src/enc/picture_enc.c
new file mode 100644
index 0000000000..3af6383d38
--- /dev/null
+++ b/media/libwebp/src/enc/picture_enc.c
@@ -0,0 +1,304 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebPPicture class basis
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "src/enc/vp8i_enc.h"
+#include "src/dsp/dsp.h"
+#include "src/utils/utils.h"
+
+//------------------------------------------------------------------------------
+// WebPPicture
+//------------------------------------------------------------------------------
+
+static int DummyWriter(const uint8_t* data, size_t data_size,
+ const WebPPicture* const picture) {
+ // The following are to prevent 'unused variable' error message.
+ (void)data;
+ (void)data_size;
+ (void)picture;
+ return 1;
+}
+
+int WebPPictureInitInternal(WebPPicture* picture, int version) {
+ if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
+ return 0; // caller/system version mismatch!
+ }
+ if (picture != NULL) {
+ memset(picture, 0, sizeof(*picture));
+ picture->writer = DummyWriter;
+ WebPEncodingSetError(picture, VP8_ENC_OK);
+ }
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+
+int WebPValidatePicture(const WebPPicture* const picture) {
+ if (picture == NULL) return 0;
+ if (picture->width <= 0 || picture->height <= 0) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_BAD_DIMENSION);
+ }
+ if (picture->width <= 0 || picture->width / 4 > INT_MAX / 4 ||
+ picture->height <= 0 || picture->height / 4 > INT_MAX / 4) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_BAD_DIMENSION);
+ }
+ if (picture->colorspace != WEBP_YUV420 &&
+ picture->colorspace != WEBP_YUV420A) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION);
+ }
+ return 1;
+}
+
+static void WebPPictureResetBufferARGB(WebPPicture* const picture) {
+ picture->memory_argb_ = NULL;
+ picture->argb = NULL;
+ picture->argb_stride = 0;
+}
+
+static void WebPPictureResetBufferYUVA(WebPPicture* const picture) {
+ picture->memory_ = NULL;
+ picture->y = picture->u = picture->v = picture->a = NULL;
+ picture->y_stride = picture->uv_stride = 0;
+ picture->a_stride = 0;
+}
+
+void WebPPictureResetBuffers(WebPPicture* const picture) {
+ WebPPictureResetBufferARGB(picture);
+ WebPPictureResetBufferYUVA(picture);
+}
+
+int WebPPictureAllocARGB(WebPPicture* const picture) {
+ void* memory;
+ const int width = picture->width;
+ const int height = picture->height;
+ const uint64_t argb_size = (uint64_t)width * height;
+
+ if (!WebPValidatePicture(picture)) return 0;
+
+ WebPSafeFree(picture->memory_argb_);
+ WebPPictureResetBufferARGB(picture);
+
+ // allocate a new buffer.
+ memory = WebPSafeMalloc(argb_size + WEBP_ALIGN_CST, sizeof(*picture->argb));
+ if (memory == NULL) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ picture->memory_argb_ = memory;
+ picture->argb = (uint32_t*)WEBP_ALIGN(memory);
+ picture->argb_stride = width;
+ return 1;
+}
+
+int WebPPictureAllocYUVA(WebPPicture* const picture) {
+ const int has_alpha = (int)picture->colorspace & WEBP_CSP_ALPHA_BIT;
+ const int width = picture->width;
+ const int height = picture->height;
+ const int y_stride = width;
+ const int uv_width = (int)(((int64_t)width + 1) >> 1);
+ const int uv_height = (int)(((int64_t)height + 1) >> 1);
+ const int uv_stride = uv_width;
+ int a_width, a_stride;
+ uint64_t y_size, uv_size, a_size, total_size;
+ uint8_t* mem;
+
+ if (!WebPValidatePicture(picture)) return 0;
+
+ WebPSafeFree(picture->memory_);
+ WebPPictureResetBufferYUVA(picture);
+
+ // alpha
+ a_width = has_alpha ? width : 0;
+ a_stride = a_width;
+ y_size = (uint64_t)y_stride * height;
+ uv_size = (uint64_t)uv_stride * uv_height;
+ a_size = (uint64_t)a_stride * height;
+
+ total_size = y_size + a_size + 2 * uv_size;
+
+ // Security and validation checks
+ if (width <= 0 || height <= 0 || // luma/alpha param error
+ uv_width <= 0 || uv_height <= 0) { // u/v param error
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_BAD_DIMENSION);
+ }
+ // allocate a new buffer.
+ mem = (uint8_t*)WebPSafeMalloc(total_size, sizeof(*mem));
+ if (mem == NULL) {
+ return WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+
+ // From now on, we're in the clear, we can no longer fail...
+ picture->memory_ = (void*)mem;
+ picture->y_stride = y_stride;
+ picture->uv_stride = uv_stride;
+ picture->a_stride = a_stride;
+
+ // TODO(skal): we could align the y/u/v planes and adjust stride.
+ picture->y = mem;
+ mem += y_size;
+
+ picture->u = mem;
+ mem += uv_size;
+ picture->v = mem;
+ mem += uv_size;
+
+ if (a_size > 0) {
+ picture->a = mem;
+ mem += a_size;
+ }
+ (void)mem; // makes the static analyzer happy
+ return 1;
+}
+
+int WebPPictureAlloc(WebPPicture* picture) {
+ if (picture != NULL) {
+ WebPPictureFree(picture); // erase previous buffer
+
+ if (!picture->use_argb) {
+ return WebPPictureAllocYUVA(picture);
+ } else {
+ return WebPPictureAllocARGB(picture);
+ }
+ }
+ return 1;
+}
+
+void WebPPictureFree(WebPPicture* picture) {
+ if (picture != NULL) {
+ WebPSafeFree(picture->memory_);
+ WebPSafeFree(picture->memory_argb_);
+ WebPPictureResetBuffers(picture);
+ }
+}
+
+//------------------------------------------------------------------------------
+// WebPMemoryWriter: Write-to-memory
+
+void WebPMemoryWriterInit(WebPMemoryWriter* writer) {
+ writer->mem = NULL;
+ writer->size = 0;
+ writer->max_size = 0;
+}
+
+int WebPMemoryWrite(const uint8_t* data, size_t data_size,
+ const WebPPicture* picture) {
+ WebPMemoryWriter* const w = (WebPMemoryWriter*)picture->custom_ptr;
+ uint64_t next_size;
+ if (w == NULL) {
+ return 1;
+ }
+ next_size = (uint64_t)w->size + data_size;
+ if (next_size > w->max_size) {
+ uint8_t* new_mem;
+ uint64_t next_max_size = 2ULL * w->max_size;
+ if (next_max_size < next_size) next_max_size = next_size;
+ if (next_max_size < 8192ULL) next_max_size = 8192ULL;
+ new_mem = (uint8_t*)WebPSafeMalloc(next_max_size, 1);
+ if (new_mem == NULL) {
+ return 0;
+ }
+ if (w->size > 0) {
+ memcpy(new_mem, w->mem, w->size);
+ }
+ WebPSafeFree(w->mem);
+ w->mem = new_mem;
+ // down-cast is ok, thanks to WebPSafeMalloc
+ w->max_size = (size_t)next_max_size;
+ }
+ if (data_size > 0) {
+ memcpy(w->mem + w->size, data, data_size);
+ w->size += data_size;
+ }
+ return 1;
+}
+
+void WebPMemoryWriterClear(WebPMemoryWriter* writer) {
+ if (writer != NULL) {
+ WebPSafeFree(writer->mem);
+ writer->mem = NULL;
+ writer->size = 0;
+ writer->max_size = 0;
+ }
+}
+
+//------------------------------------------------------------------------------
+// Simplest high-level calls:
+
+typedef int (*Importer)(WebPPicture* const, const uint8_t* const, int);
+
+static size_t Encode(const uint8_t* rgba, int width, int height, int stride,
+ Importer import, float quality_factor, int lossless,
+ uint8_t** output) {
+ WebPPicture pic;
+ WebPConfig config;
+ WebPMemoryWriter wrt;
+ int ok;
+
+ if (output == NULL) return 0;
+
+ if (!WebPConfigPreset(&config, WEBP_PRESET_DEFAULT, quality_factor) ||
+ !WebPPictureInit(&pic)) {
+ return 0; // shouldn't happen, except if system installation is broken
+ }
+
+ config.lossless = !!lossless;
+ pic.use_argb = !!lossless;
+ pic.width = width;
+ pic.height = height;
+ pic.writer = WebPMemoryWrite;
+ pic.custom_ptr = &wrt;
+ WebPMemoryWriterInit(&wrt);
+
+ ok = import(&pic, rgba, stride) && WebPEncode(&config, &pic);
+ WebPPictureFree(&pic);
+ if (!ok) {
+ WebPMemoryWriterClear(&wrt);
+ *output = NULL;
+ return 0;
+ }
+ *output = wrt.mem;
+ return wrt.size;
+}
+
+#define ENCODE_FUNC(NAME, IMPORTER) \
+size_t NAME(const uint8_t* in, int w, int h, int bps, float q, \
+ uint8_t** out) { \
+ return Encode(in, w, h, bps, IMPORTER, q, 0, out); \
+}
+
+ENCODE_FUNC(WebPEncodeRGB, WebPPictureImportRGB)
+ENCODE_FUNC(WebPEncodeRGBA, WebPPictureImportRGBA)
+#if !defined(WEBP_REDUCE_CSP)
+ENCODE_FUNC(WebPEncodeBGR, WebPPictureImportBGR)
+ENCODE_FUNC(WebPEncodeBGRA, WebPPictureImportBGRA)
+#endif // WEBP_REDUCE_CSP
+
+#undef ENCODE_FUNC
+
+#define LOSSLESS_DEFAULT_QUALITY 70.
+#define LOSSLESS_ENCODE_FUNC(NAME, IMPORTER) \
+size_t NAME(const uint8_t* in, int w, int h, int bps, uint8_t** out) { \
+ return Encode(in, w, h, bps, IMPORTER, LOSSLESS_DEFAULT_QUALITY, 1, out); \
+}
+
+LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessRGB, WebPPictureImportRGB)
+LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessRGBA, WebPPictureImportRGBA)
+#if !defined(WEBP_REDUCE_CSP)
+LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessBGR, WebPPictureImportBGR)
+LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessBGRA, WebPPictureImportBGRA)
+#endif // WEBP_REDUCE_CSP
+
+#undef LOSSLESS_ENCODE_FUNC
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/picture_psnr_enc.c b/media/libwebp/src/enc/picture_psnr_enc.c
new file mode 100644
index 0000000000..1a2f0bef3e
--- /dev/null
+++ b/media/libwebp/src/enc/picture_psnr_enc.c
@@ -0,0 +1,258 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebPPicture tools for measuring distortion
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "src/webp/encode.h"
+
+#if !(defined(WEBP_DISABLE_STATS) || defined(WEBP_REDUCE_SIZE))
+
+#include <math.h>
+#include <stdlib.h>
+
+#include "src/dsp/dsp.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/utils/utils.h"
+
+typedef double (*AccumulateFunc)(const uint8_t* src, int src_stride,
+ const uint8_t* ref, int ref_stride,
+ int w, int h);
+
+//------------------------------------------------------------------------------
+// local-min distortion
+//
+// For every pixel in the *reference* picture, we search for the local best
+// match in the compressed image. This is not a symmetrical measure.
+
+#define RADIUS 2 // search radius. Shouldn't be too large.
+
+static double AccumulateLSIM(const uint8_t* src, int src_stride,
+ const uint8_t* ref, int ref_stride,
+ int w, int h) {
+ int x, y;
+ double total_sse = 0.;
+ for (y = 0; y < h; ++y) {
+ const int y_0 = (y - RADIUS < 0) ? 0 : y - RADIUS;
+ const int y_1 = (y + RADIUS + 1 >= h) ? h : y + RADIUS + 1;
+ for (x = 0; x < w; ++x) {
+ const int x_0 = (x - RADIUS < 0) ? 0 : x - RADIUS;
+ const int x_1 = (x + RADIUS + 1 >= w) ? w : x + RADIUS + 1;
+ double best_sse = 255. * 255.;
+ const double value = (double)ref[y * ref_stride + x];
+ int i, j;
+ for (j = y_0; j < y_1; ++j) {
+ const uint8_t* const s = src + j * src_stride;
+ for (i = x_0; i < x_1; ++i) {
+ const double diff = s[i] - value;
+ const double sse = diff * diff;
+ if (sse < best_sse) best_sse = sse;
+ }
+ }
+ total_sse += best_sse;
+ }
+ }
+ return total_sse;
+}
+#undef RADIUS
+
+static double AccumulateSSE(const uint8_t* src, int src_stride,
+ const uint8_t* ref, int ref_stride,
+ int w, int h) {
+ int y;
+ double total_sse = 0.;
+ for (y = 0; y < h; ++y) {
+ total_sse += VP8AccumulateSSE(src, ref, w);
+ src += src_stride;
+ ref += ref_stride;
+ }
+ return total_sse;
+}
+
+//------------------------------------------------------------------------------
+
+static double AccumulateSSIM(const uint8_t* src, int src_stride,
+ const uint8_t* ref, int ref_stride,
+ int w, int h) {
+ const int w0 = (w < VP8_SSIM_KERNEL) ? w : VP8_SSIM_KERNEL;
+ const int w1 = w - VP8_SSIM_KERNEL - 1;
+ const int h0 = (h < VP8_SSIM_KERNEL) ? h : VP8_SSIM_KERNEL;
+ const int h1 = h - VP8_SSIM_KERNEL - 1;
+ int x, y;
+ double sum = 0.;
+ for (y = 0; y < h0; ++y) {
+ for (x = 0; x < w; ++x) {
+ sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h);
+ }
+ }
+ for (; y < h1; ++y) {
+ for (x = 0; x < w0; ++x) {
+ sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h);
+ }
+ for (; x < w1; ++x) {
+ const int off1 = x - VP8_SSIM_KERNEL + (y - VP8_SSIM_KERNEL) * src_stride;
+ const int off2 = x - VP8_SSIM_KERNEL + (y - VP8_SSIM_KERNEL) * ref_stride;
+ sum += VP8SSIMGet(src + off1, src_stride, ref + off2, ref_stride);
+ }
+ for (; x < w; ++x) {
+ sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h);
+ }
+ }
+ for (; y < h; ++y) {
+ for (x = 0; x < w; ++x) {
+ sum += VP8SSIMGetClipped(src, src_stride, ref, ref_stride, x, y, w, h);
+ }
+ }
+ return sum;
+}
+
+//------------------------------------------------------------------------------
+// Distortion
+
+// Max value returned in case of exact similarity.
+static const double kMinDistortion_dB = 99.;
+
+static double GetPSNR(double v, double size) {
+ return (v > 0. && size > 0.) ? -4.3429448 * log(v / (size * 255 * 255.))
+ : kMinDistortion_dB;
+}
+
+static double GetLogSSIM(double v, double size) {
+ v = (size > 0.) ? v / size : 1.;
+ return (v < 1.) ? -10.0 * log10(1. - v) : kMinDistortion_dB;
+}
+
+int WebPPlaneDistortion(const uint8_t* src, size_t src_stride,
+ const uint8_t* ref, size_t ref_stride,
+ int width, int height, size_t x_step,
+ int type, float* distortion, float* result) {
+ uint8_t* allocated = NULL;
+ const AccumulateFunc metric = (type == 0) ? AccumulateSSE :
+ (type == 1) ? AccumulateSSIM :
+ AccumulateLSIM;
+ if (src == NULL || ref == NULL ||
+ src_stride < x_step * width || ref_stride < x_step * width ||
+ result == NULL || distortion == NULL) {
+ return 0;
+ }
+
+ VP8SSIMDspInit();
+ if (x_step != 1) { // extract a packed plane if needed
+ int x, y;
+ uint8_t* tmp1;
+ uint8_t* tmp2;
+ allocated =
+ (uint8_t*)WebPSafeMalloc(2ULL * width * height, sizeof(*allocated));
+ if (allocated == NULL) return 0;
+ tmp1 = allocated;
+ tmp2 = tmp1 + (size_t)width * height;
+ for (y = 0; y < height; ++y) {
+ for (x = 0; x < width; ++x) {
+ tmp1[x + y * width] = src[x * x_step + y * src_stride];
+ tmp2[x + y * width] = ref[x * x_step + y * ref_stride];
+ }
+ }
+ src = tmp1;
+ ref = tmp2;
+ }
+ *distortion = (float)metric(src, width, ref, width, width, height);
+ WebPSafeFree(allocated);
+
+ *result = (type == 1) ? (float)GetLogSSIM(*distortion, (double)width * height)
+ : (float)GetPSNR(*distortion, (double)width * height);
+ return 1;
+}
+
+#ifdef WORDS_BIGENDIAN
+#define BLUE_OFFSET 3 // uint32_t 0x000000ff is 0x00,00,00,ff in memory
+#else
+#define BLUE_OFFSET 0 // uint32_t 0x000000ff is 0xff,00,00,00 in memory
+#endif
+
+int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref,
+ int type, float results[5]) {
+ int w, h, c;
+ int ok = 0;
+ WebPPicture p0, p1;
+ double total_size = 0., total_distortion = 0.;
+ if (src == NULL || ref == NULL ||
+ src->width != ref->width || src->height != ref->height ||
+ results == NULL) {
+ return 0;
+ }
+
+ VP8SSIMDspInit();
+ if (!WebPPictureInit(&p0) || !WebPPictureInit(&p1)) return 0;
+ w = src->width;
+ h = src->height;
+ if (!WebPPictureView(src, 0, 0, w, h, &p0)) goto Error;
+ if (!WebPPictureView(ref, 0, 0, w, h, &p1)) goto Error;
+
+ // We always measure distortion in ARGB space.
+ if (p0.use_argb == 0 && !WebPPictureYUVAToARGB(&p0)) goto Error;
+ if (p1.use_argb == 0 && !WebPPictureYUVAToARGB(&p1)) goto Error;
+ for (c = 0; c < 4; ++c) {
+ float distortion;
+ const size_t stride0 = 4 * (size_t)p0.argb_stride;
+ const size_t stride1 = 4 * (size_t)p1.argb_stride;
+ // results are reported as BGRA
+ const int offset = c ^ BLUE_OFFSET;
+ if (!WebPPlaneDistortion((const uint8_t*)p0.argb + offset, stride0,
+ (const uint8_t*)p1.argb + offset, stride1,
+ w, h, 4, type, &distortion, results + c)) {
+ goto Error;
+ }
+ total_distortion += distortion;
+ total_size += w * h;
+ }
+
+ results[4] = (type == 1) ? (float)GetLogSSIM(total_distortion, total_size)
+ : (float)GetPSNR(total_distortion, total_size);
+ ok = 1;
+
+ Error:
+ WebPPictureFree(&p0);
+ WebPPictureFree(&p1);
+ return ok;
+}
+
+#undef BLUE_OFFSET
+
+#else // defined(WEBP_DISABLE_STATS)
+int WebPPlaneDistortion(const uint8_t* src, size_t src_stride,
+ const uint8_t* ref, size_t ref_stride,
+ int width, int height, size_t x_step,
+ int type, float* distortion, float* result) {
+ (void)src;
+ (void)src_stride;
+ (void)ref;
+ (void)ref_stride;
+ (void)width;
+ (void)height;
+ (void)x_step;
+ (void)type;
+ if (distortion == NULL || result == NULL) return 0;
+ *distortion = 0.f;
+ *result = 0.f;
+ return 1;
+}
+
+int WebPPictureDistortion(const WebPPicture* src, const WebPPicture* ref,
+ int type, float results[5]) {
+ int i;
+ (void)src;
+ (void)ref;
+ (void)type;
+ if (results == NULL) return 0;
+ for (i = 0; i < 5; ++i) results[i] = 0.f;
+ return 1;
+}
+
+#endif // !defined(WEBP_DISABLE_STATS)
diff --git a/media/libwebp/src/enc/picture_rescale_enc.c b/media/libwebp/src/enc/picture_rescale_enc.c
new file mode 100644
index 0000000000..839f91cacc
--- /dev/null
+++ b/media/libwebp/src/enc/picture_rescale_enc.c
@@ -0,0 +1,300 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebPPicture tools: copy, crop, rescaling and view.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "src/webp/encode.h"
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "src/enc/vp8i_enc.h"
+
+#if !defined(WEBP_REDUCE_SIZE)
+#include "src/utils/rescaler_utils.h"
+#include "src/utils/utils.h"
+#endif // !defined(WEBP_REDUCE_SIZE)
+
+#define HALVE(x) (((x) + 1) >> 1)
+
+// Grab the 'specs' (writer, *opaque, width, height...) from 'src' and copy them
+// into 'dst'. Mark 'dst' as not owning any memory.
+static void PictureGrabSpecs(const WebPPicture* const src,
+ WebPPicture* const dst) {
+ assert(src != NULL && dst != NULL);
+ *dst = *src;
+ WebPPictureResetBuffers(dst);
+}
+
+//------------------------------------------------------------------------------
+
+// Adjust top-left corner to chroma sample position.
+static void SnapTopLeftPosition(const WebPPicture* const pic,
+ int* const left, int* const top) {
+ if (!pic->use_argb) {
+ *left &= ~1;
+ *top &= ~1;
+ }
+}
+
+// Adjust top-left corner and verify that the sub-rectangle is valid.
+static int AdjustAndCheckRectangle(const WebPPicture* const pic,
+ int* const left, int* const top,
+ int width, int height) {
+ SnapTopLeftPosition(pic, left, top);
+ if ((*left) < 0 || (*top) < 0) return 0;
+ if (width <= 0 || height <= 0) return 0;
+ if ((*left) + width > pic->width) return 0;
+ if ((*top) + height > pic->height) return 0;
+ return 1;
+}
+
+#if !defined(WEBP_REDUCE_SIZE)
+int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) {
+ if (src == NULL || dst == NULL) return 0;
+ if (src == dst) return 1;
+
+ PictureGrabSpecs(src, dst);
+ if (!WebPPictureAlloc(dst)) return 0;
+
+ if (!src->use_argb) {
+ WebPCopyPlane(src->y, src->y_stride,
+ dst->y, dst->y_stride, dst->width, dst->height);
+ WebPCopyPlane(src->u, src->uv_stride, dst->u, dst->uv_stride,
+ HALVE(dst->width), HALVE(dst->height));
+ WebPCopyPlane(src->v, src->uv_stride, dst->v, dst->uv_stride,
+ HALVE(dst->width), HALVE(dst->height));
+ if (dst->a != NULL) {
+ WebPCopyPlane(src->a, src->a_stride,
+ dst->a, dst->a_stride, dst->width, dst->height);
+ }
+ } else {
+ WebPCopyPlane((const uint8_t*)src->argb, 4 * src->argb_stride,
+ (uint8_t*)dst->argb, 4 * dst->argb_stride,
+ 4 * dst->width, dst->height);
+ }
+ return 1;
+}
+#endif // !defined(WEBP_REDUCE_SIZE)
+
+int WebPPictureIsView(const WebPPicture* picture) {
+ if (picture == NULL) return 0;
+ if (picture->use_argb) {
+ return (picture->memory_argb_ == NULL);
+ }
+ return (picture->memory_ == NULL);
+}
+
+int WebPPictureView(const WebPPicture* src,
+ int left, int top, int width, int height,
+ WebPPicture* dst) {
+ if (src == NULL || dst == NULL) return 0;
+
+ // verify rectangle position.
+ if (!AdjustAndCheckRectangle(src, &left, &top, width, height)) return 0;
+
+ if (src != dst) { // beware of aliasing! We don't want to leak 'memory_'.
+ PictureGrabSpecs(src, dst);
+ }
+ dst->width = width;
+ dst->height = height;
+ if (!src->use_argb) {
+ dst->y = src->y + top * src->y_stride + left;
+ dst->u = src->u + (top >> 1) * src->uv_stride + (left >> 1);
+ dst->v = src->v + (top >> 1) * src->uv_stride + (left >> 1);
+ dst->y_stride = src->y_stride;
+ dst->uv_stride = src->uv_stride;
+ if (src->a != NULL) {
+ dst->a = src->a + top * src->a_stride + left;
+ dst->a_stride = src->a_stride;
+ }
+ } else {
+ dst->argb = src->argb + top * src->argb_stride + left;
+ dst->argb_stride = src->argb_stride;
+ }
+ return 1;
+}
+
+#if !defined(WEBP_REDUCE_SIZE)
+//------------------------------------------------------------------------------
+// Picture cropping
+
+int WebPPictureCrop(WebPPicture* pic,
+ int left, int top, int width, int height) {
+ WebPPicture tmp;
+
+ if (pic == NULL) return 0;
+ if (!AdjustAndCheckRectangle(pic, &left, &top, width, height)) return 0;
+
+ PictureGrabSpecs(pic, &tmp);
+ tmp.width = width;
+ tmp.height = height;
+ if (!WebPPictureAlloc(&tmp)) return 0;
+
+ if (!pic->use_argb) {
+ const int y_offset = top * pic->y_stride + left;
+ const int uv_offset = (top / 2) * pic->uv_stride + left / 2;
+ WebPCopyPlane(pic->y + y_offset, pic->y_stride,
+ tmp.y, tmp.y_stride, width, height);
+ WebPCopyPlane(pic->u + uv_offset, pic->uv_stride,
+ tmp.u, tmp.uv_stride, HALVE(width), HALVE(height));
+ WebPCopyPlane(pic->v + uv_offset, pic->uv_stride,
+ tmp.v, tmp.uv_stride, HALVE(width), HALVE(height));
+
+ if (tmp.a != NULL) {
+ const int a_offset = top * pic->a_stride + left;
+ WebPCopyPlane(pic->a + a_offset, pic->a_stride,
+ tmp.a, tmp.a_stride, width, height);
+ }
+ } else {
+ const uint8_t* const src =
+ (const uint8_t*)(pic->argb + top * pic->argb_stride + left);
+ WebPCopyPlane(src, pic->argb_stride * 4, (uint8_t*)tmp.argb,
+ tmp.argb_stride * 4, width * 4, height);
+ }
+ WebPPictureFree(pic);
+ *pic = tmp;
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+// Simple picture rescaler
+
+static int RescalePlane(const uint8_t* src,
+ int src_width, int src_height, int src_stride,
+ uint8_t* dst,
+ int dst_width, int dst_height, int dst_stride,
+ rescaler_t* const work,
+ int num_channels) {
+ WebPRescaler rescaler;
+ int y = 0;
+ if (!WebPRescalerInit(&rescaler, src_width, src_height,
+ dst, dst_width, dst_height, dst_stride,
+ num_channels, work)) {
+ return 0;
+ }
+ while (y < src_height) {
+ y += WebPRescalerImport(&rescaler, src_height - y,
+ src + y * src_stride, src_stride);
+ WebPRescalerExport(&rescaler);
+ }
+ return 1;
+}
+
+static void AlphaMultiplyARGB(WebPPicture* const pic, int inverse) {
+ assert(pic->argb != NULL);
+ WebPMultARGBRows((uint8_t*)pic->argb, pic->argb_stride * sizeof(*pic->argb),
+ pic->width, pic->height, inverse);
+}
+
+static void AlphaMultiplyY(WebPPicture* const pic, int inverse) {
+ if (pic->a != NULL) {
+ WebPMultRows(pic->y, pic->y_stride, pic->a, pic->a_stride,
+ pic->width, pic->height, inverse);
+ }
+}
+
+int WebPPictureRescale(WebPPicture* picture, int width, int height) {
+ WebPPicture tmp;
+ int prev_width, prev_height;
+ rescaler_t* work;
+
+ if (picture == NULL) return 0;
+ prev_width = picture->width;
+ prev_height = picture->height;
+ if (!WebPRescalerGetScaledDimensions(
+ prev_width, prev_height, &width, &height)) {
+ return 0;
+ }
+
+ PictureGrabSpecs(picture, &tmp);
+ tmp.width = width;
+ tmp.height = height;
+ if (!WebPPictureAlloc(&tmp)) return 0;
+
+ if (!picture->use_argb) {
+ work = (rescaler_t*)WebPSafeMalloc(2ULL * width, sizeof(*work));
+ if (work == NULL) {
+ WebPPictureFree(&tmp);
+ return 0;
+ }
+ // If present, we need to rescale alpha first (for AlphaMultiplyY).
+ if (picture->a != NULL) {
+ WebPInitAlphaProcessing();
+ if (!RescalePlane(picture->a, prev_width, prev_height, picture->a_stride,
+ tmp.a, width, height, tmp.a_stride, work, 1)) {
+ return 0;
+ }
+ }
+
+ // We take transparency into account on the luma plane only. That's not
+ // totally exact blending, but still is a good approximation.
+ AlphaMultiplyY(picture, 0);
+ if (!RescalePlane(picture->y, prev_width, prev_height, picture->y_stride,
+ tmp.y, width, height, tmp.y_stride, work, 1) ||
+ !RescalePlane(picture->u, HALVE(prev_width), HALVE(prev_height),
+ picture->uv_stride, tmp.u, HALVE(width), HALVE(height),
+ tmp.uv_stride, work, 1) ||
+ !RescalePlane(picture->v, HALVE(prev_width), HALVE(prev_height),
+ picture->uv_stride, tmp.v, HALVE(width), HALVE(height),
+ tmp.uv_stride, work, 1)) {
+ return 0;
+ }
+ AlphaMultiplyY(&tmp, 1);
+ } else {
+ work = (rescaler_t*)WebPSafeMalloc(2ULL * width * 4, sizeof(*work));
+ if (work == NULL) {
+ WebPPictureFree(&tmp);
+ return 0;
+ }
+ // In order to correctly interpolate colors, we need to apply the alpha
+ // weighting first (black-matting), scale the RGB values, and remove
+ // the premultiplication afterward (while preserving the alpha channel).
+ WebPInitAlphaProcessing();
+ AlphaMultiplyARGB(picture, 0);
+ if (!RescalePlane((const uint8_t*)picture->argb, prev_width, prev_height,
+ picture->argb_stride * 4, (uint8_t*)tmp.argb, width,
+ height, tmp.argb_stride * 4, work, 4)) {
+ return 0;
+ }
+ AlphaMultiplyARGB(&tmp, 1);
+ }
+ WebPPictureFree(picture);
+ WebPSafeFree(work);
+ *picture = tmp;
+ return 1;
+}
+
+#else // defined(WEBP_REDUCE_SIZE)
+
+int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) {
+ (void)src;
+ (void)dst;
+ return 0;
+}
+
+int WebPPictureCrop(WebPPicture* pic,
+ int left, int top, int width, int height) {
+ (void)pic;
+ (void)left;
+ (void)top;
+ (void)width;
+ (void)height;
+ return 0;
+}
+
+int WebPPictureRescale(WebPPicture* pic, int width, int height) {
+ (void)pic;
+ (void)width;
+ (void)height;
+ return 0;
+}
+#endif // !defined(WEBP_REDUCE_SIZE)
diff --git a/media/libwebp/src/enc/picture_tools_enc.c b/media/libwebp/src/enc/picture_tools_enc.c
new file mode 100644
index 0000000000..147cc18608
--- /dev/null
+++ b/media/libwebp/src/enc/picture_tools_enc.c
@@ -0,0 +1,274 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebPPicture tools: alpha handling, etc.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+
+#include "src/enc/vp8i_enc.h"
+#include "src/dsp/yuv.h"
+
+//------------------------------------------------------------------------------
+// Helper: clean up fully transparent area to help compressibility.
+
+#define SIZE 8
+#define SIZE2 (SIZE / 2)
+static int IsTransparentARGBArea(const uint32_t* ptr, int stride, int size) {
+ int y, x;
+ for (y = 0; y < size; ++y) {
+ for (x = 0; x < size; ++x) {
+ if (ptr[x] & 0xff000000u) {
+ return 0;
+ }
+ }
+ ptr += stride;
+ }
+ return 1;
+}
+
+static void Flatten(uint8_t* ptr, int v, int stride, int size) {
+ int y;
+ for (y = 0; y < size; ++y) {
+ memset(ptr, v, size);
+ ptr += stride;
+ }
+}
+
+static void FlattenARGB(uint32_t* ptr, uint32_t v, int stride, int size) {
+ int x, y;
+ for (y = 0; y < size; ++y) {
+ for (x = 0; x < size; ++x) ptr[x] = v;
+ ptr += stride;
+ }
+}
+
+// Smoothen the luma components of transparent pixels. Return true if the whole
+// block is transparent.
+static int SmoothenBlock(const uint8_t* a_ptr, int a_stride, uint8_t* y_ptr,
+ int y_stride, int width, int height) {
+ int sum = 0, count = 0;
+ int x, y;
+ const uint8_t* alpha_ptr = a_ptr;
+ uint8_t* luma_ptr = y_ptr;
+ for (y = 0; y < height; ++y) {
+ for (x = 0; x < width; ++x) {
+ if (alpha_ptr[x] != 0) {
+ ++count;
+ sum += luma_ptr[x];
+ }
+ }
+ alpha_ptr += a_stride;
+ luma_ptr += y_stride;
+ }
+ if (count > 0 && count < width * height) {
+ const uint8_t avg_u8 = (uint8_t)(sum / count);
+ alpha_ptr = a_ptr;
+ luma_ptr = y_ptr;
+ for (y = 0; y < height; ++y) {
+ for (x = 0; x < width; ++x) {
+ if (alpha_ptr[x] == 0) luma_ptr[x] = avg_u8;
+ }
+ alpha_ptr += a_stride;
+ luma_ptr += y_stride;
+ }
+ }
+ return (count == 0);
+}
+
+void WebPReplaceTransparentPixels(WebPPicture* const pic, uint32_t color) {
+ if (pic != NULL && pic->use_argb) {
+ int y = pic->height;
+ uint32_t* argb = pic->argb;
+ color &= 0xffffffu; // force alpha=0
+ WebPInitAlphaProcessing();
+ while (y-- > 0) {
+ WebPAlphaReplace(argb, pic->width, color);
+ argb += pic->argb_stride;
+ }
+ }
+}
+
+void WebPCleanupTransparentArea(WebPPicture* pic) {
+ int x, y, w, h;
+ if (pic == NULL) return;
+ w = pic->width / SIZE;
+ h = pic->height / SIZE;
+
+ // note: we ignore the left-overs on right/bottom, except for SmoothenBlock().
+ if (pic->use_argb) {
+ uint32_t argb_value = 0;
+ for (y = 0; y < h; ++y) {
+ int need_reset = 1;
+ for (x = 0; x < w; ++x) {
+ const int off = (y * pic->argb_stride + x) * SIZE;
+ if (IsTransparentARGBArea(pic->argb + off, pic->argb_stride, SIZE)) {
+ if (need_reset) {
+ argb_value = pic->argb[off];
+ need_reset = 0;
+ }
+ FlattenARGB(pic->argb + off, argb_value, pic->argb_stride, SIZE);
+ } else {
+ need_reset = 1;
+ }
+ }
+ }
+ } else {
+ const int width = pic->width;
+ const int height = pic->height;
+ const int y_stride = pic->y_stride;
+ const int uv_stride = pic->uv_stride;
+ const int a_stride = pic->a_stride;
+ uint8_t* y_ptr = pic->y;
+ uint8_t* u_ptr = pic->u;
+ uint8_t* v_ptr = pic->v;
+ const uint8_t* a_ptr = pic->a;
+ int values[3] = { 0 };
+ if (a_ptr == NULL || y_ptr == NULL || u_ptr == NULL || v_ptr == NULL) {
+ return;
+ }
+ for (y = 0; y + SIZE <= height; y += SIZE) {
+ int need_reset = 1;
+ for (x = 0; x + SIZE <= width; x += SIZE) {
+ if (SmoothenBlock(a_ptr + x, a_stride, y_ptr + x, y_stride,
+ SIZE, SIZE)) {
+ if (need_reset) {
+ values[0] = y_ptr[x];
+ values[1] = u_ptr[x >> 1];
+ values[2] = v_ptr[x >> 1];
+ need_reset = 0;
+ }
+ Flatten(y_ptr + x, values[0], y_stride, SIZE);
+ Flatten(u_ptr + (x >> 1), values[1], uv_stride, SIZE2);
+ Flatten(v_ptr + (x >> 1), values[2], uv_stride, SIZE2);
+ } else {
+ need_reset = 1;
+ }
+ }
+ if (x < width) {
+ SmoothenBlock(a_ptr + x, a_stride, y_ptr + x, y_stride,
+ width - x, SIZE);
+ }
+ a_ptr += SIZE * a_stride;
+ y_ptr += SIZE * y_stride;
+ u_ptr += SIZE2 * uv_stride;
+ v_ptr += SIZE2 * uv_stride;
+ }
+ if (y < height) {
+ const int sub_height = height - y;
+ for (x = 0; x + SIZE <= width; x += SIZE) {
+ SmoothenBlock(a_ptr + x, a_stride, y_ptr + x, y_stride,
+ SIZE, sub_height);
+ }
+ if (x < width) {
+ SmoothenBlock(a_ptr + x, a_stride, y_ptr + x, y_stride,
+ width - x, sub_height);
+ }
+ }
+ }
+}
+
+#undef SIZE
+#undef SIZE2
+
+//------------------------------------------------------------------------------
+// Blend color and remove transparency info
+
+#define BLEND(V0, V1, ALPHA) \
+ ((((V0) * (255 - (ALPHA)) + (V1) * (ALPHA)) * 0x101 + 256) >> 16)
+#define BLEND_10BIT(V0, V1, ALPHA) \
+ ((((V0) * (1020 - (ALPHA)) + (V1) * (ALPHA)) * 0x101 + 1024) >> 18)
+
+static WEBP_INLINE uint32_t MakeARGB32(int r, int g, int b) {
+ return (0xff000000u | (r << 16) | (g << 8) | b);
+}
+
+void WebPBlendAlpha(WebPPicture* picture, uint32_t background_rgb) {
+ const int red = (background_rgb >> 16) & 0xff;
+ const int green = (background_rgb >> 8) & 0xff;
+ const int blue = (background_rgb >> 0) & 0xff;
+ int x, y;
+ if (picture == NULL) return;
+ if (!picture->use_argb) {
+ // omit last pixel during u/v loop
+ const int uv_width = (picture->width >> 1);
+ const int Y0 = VP8RGBToY(red, green, blue, YUV_HALF);
+ // VP8RGBToU/V expects the u/v values summed over four pixels
+ const int U0 = VP8RGBToU(4 * red, 4 * green, 4 * blue, 4 * YUV_HALF);
+ const int V0 = VP8RGBToV(4 * red, 4 * green, 4 * blue, 4 * YUV_HALF);
+ const int has_alpha = picture->colorspace & WEBP_CSP_ALPHA_BIT;
+ uint8_t* y_ptr = picture->y;
+ uint8_t* u_ptr = picture->u;
+ uint8_t* v_ptr = picture->v;
+ uint8_t* a_ptr = picture->a;
+ if (!has_alpha || a_ptr == NULL) return; // nothing to do
+ for (y = 0; y < picture->height; ++y) {
+ // Luma blending
+ for (x = 0; x < picture->width; ++x) {
+ const uint8_t alpha = a_ptr[x];
+ if (alpha < 0xff) {
+ y_ptr[x] = BLEND(Y0, y_ptr[x], alpha);
+ }
+ }
+ // Chroma blending every even line
+ if ((y & 1) == 0) {
+ uint8_t* const a_ptr2 =
+ (y + 1 == picture->height) ? a_ptr : a_ptr + picture->a_stride;
+ for (x = 0; x < uv_width; ++x) {
+ // Average four alpha values into a single blending weight.
+ // TODO(skal): might lead to visible contouring. Can we do better?
+ const uint32_t alpha =
+ a_ptr[2 * x + 0] + a_ptr[2 * x + 1] +
+ a_ptr2[2 * x + 0] + a_ptr2[2 * x + 1];
+ u_ptr[x] = BLEND_10BIT(U0, u_ptr[x], alpha);
+ v_ptr[x] = BLEND_10BIT(V0, v_ptr[x], alpha);
+ }
+ if (picture->width & 1) { // rightmost pixel
+ const uint32_t alpha = 2 * (a_ptr[2 * x + 0] + a_ptr2[2 * x + 0]);
+ u_ptr[x] = BLEND_10BIT(U0, u_ptr[x], alpha);
+ v_ptr[x] = BLEND_10BIT(V0, v_ptr[x], alpha);
+ }
+ } else {
+ u_ptr += picture->uv_stride;
+ v_ptr += picture->uv_stride;
+ }
+ memset(a_ptr, 0xff, picture->width); // reset alpha value to opaque
+ a_ptr += picture->a_stride;
+ y_ptr += picture->y_stride;
+ }
+ } else {
+ uint32_t* argb = picture->argb;
+ const uint32_t background = MakeARGB32(red, green, blue);
+ for (y = 0; y < picture->height; ++y) {
+ for (x = 0; x < picture->width; ++x) {
+ const int alpha = (argb[x] >> 24) & 0xff;
+ if (alpha != 0xff) {
+ if (alpha > 0) {
+ int r = (argb[x] >> 16) & 0xff;
+ int g = (argb[x] >> 8) & 0xff;
+ int b = (argb[x] >> 0) & 0xff;
+ r = BLEND(red, r, alpha);
+ g = BLEND(green, g, alpha);
+ b = BLEND(blue, b, alpha);
+ argb[x] = MakeARGB32(r, g, b);
+ } else {
+ argb[x] = background;
+ }
+ }
+ }
+ argb += picture->argb_stride;
+ }
+ }
+}
+
+#undef BLEND
+#undef BLEND_10BIT
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/predictor_enc.c b/media/libwebp/src/enc/predictor_enc.c
new file mode 100644
index 0000000000..b3d44b59d5
--- /dev/null
+++ b/media/libwebp/src/enc/predictor_enc.c
@@ -0,0 +1,792 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Image transform methods for lossless encoder.
+//
+// Authors: Vikas Arora (vikaas.arora@gmail.com)
+// Jyrki Alakuijala (jyrki@google.com)
+// Urvang Joshi (urvang@google.com)
+// Vincent Rabaud (vrabaud@google.com)
+
+#include "src/dsp/lossless.h"
+#include "src/dsp/lossless_common.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/enc/vp8li_enc.h"
+
+#define MAX_DIFF_COST (1e30f)
+
+static const float kSpatialPredictorBias = 15.f;
+static const int kPredLowEffort = 11;
+static const uint32_t kMaskAlpha = 0xff000000;
+
+// Mostly used to reduce code size + readability
+static WEBP_INLINE int GetMin(int a, int b) { return (a > b) ? b : a; }
+
+//------------------------------------------------------------------------------
+// Methods to calculate Entropy (Shannon).
+
+static float PredictionCostSpatial(const int counts[256], int weight_0,
+ float exp_val) {
+ const int significant_symbols = 256 >> 4;
+ const float exp_decay_factor = 0.6f;
+ float bits = (float)weight_0 * counts[0];
+ int i;
+ for (i = 1; i < significant_symbols; ++i) {
+ bits += exp_val * (counts[i] + counts[256 - i]);
+ exp_val *= exp_decay_factor;
+ }
+ return (float)(-0.1 * bits);
+}
+
+static float PredictionCostSpatialHistogram(const int accumulated[4][256],
+ const int tile[4][256]) {
+ int i;
+ float retval = 0.f;
+ for (i = 0; i < 4; ++i) {
+ const float kExpValue = 0.94f;
+ retval += PredictionCostSpatial(tile[i], 1, kExpValue);
+ retval += VP8LCombinedShannonEntropy(tile[i], accumulated[i]);
+ }
+ return (float)retval;
+}
+
+static WEBP_INLINE void UpdateHisto(int histo_argb[4][256], uint32_t argb) {
+ ++histo_argb[0][argb >> 24];
+ ++histo_argb[1][(argb >> 16) & 0xff];
+ ++histo_argb[2][(argb >> 8) & 0xff];
+ ++histo_argb[3][argb & 0xff];
+}
+
+//------------------------------------------------------------------------------
+// Spatial transform functions.
+
+static WEBP_INLINE void PredictBatch(int mode, int x_start, int y,
+ int num_pixels, const uint32_t* current,
+ const uint32_t* upper, uint32_t* out) {
+ if (x_start == 0) {
+ if (y == 0) {
+ // ARGB_BLACK.
+ VP8LPredictorsSub[0](current, NULL, 1, out);
+ } else {
+ // Top one.
+ VP8LPredictorsSub[2](current, upper, 1, out);
+ }
+ ++x_start;
+ ++out;
+ --num_pixels;
+ }
+ if (y == 0) {
+ // Left one.
+ VP8LPredictorsSub[1](current + x_start, NULL, num_pixels, out);
+ } else {
+ VP8LPredictorsSub[mode](current + x_start, upper + x_start, num_pixels,
+ out);
+ }
+}
+
+#if (WEBP_NEAR_LOSSLESS == 1)
+static WEBP_INLINE int GetMax(int a, int b) { return (a < b) ? b : a; }
+
+static int MaxDiffBetweenPixels(uint32_t p1, uint32_t p2) {
+ const int diff_a = abs((int)(p1 >> 24) - (int)(p2 >> 24));
+ const int diff_r = abs((int)((p1 >> 16) & 0xff) - (int)((p2 >> 16) & 0xff));
+ const int diff_g = abs((int)((p1 >> 8) & 0xff) - (int)((p2 >> 8) & 0xff));
+ const int diff_b = abs((int)(p1 & 0xff) - (int)(p2 & 0xff));
+ return GetMax(GetMax(diff_a, diff_r), GetMax(diff_g, diff_b));
+}
+
+static int MaxDiffAroundPixel(uint32_t current, uint32_t up, uint32_t down,
+ uint32_t left, uint32_t right) {
+ const int diff_up = MaxDiffBetweenPixels(current, up);
+ const int diff_down = MaxDiffBetweenPixels(current, down);
+ const int diff_left = MaxDiffBetweenPixels(current, left);
+ const int diff_right = MaxDiffBetweenPixels(current, right);
+ return GetMax(GetMax(diff_up, diff_down), GetMax(diff_left, diff_right));
+}
+
+static uint32_t AddGreenToBlueAndRed(uint32_t argb) {
+ const uint32_t green = (argb >> 8) & 0xff;
+ uint32_t red_blue = argb & 0x00ff00ffu;
+ red_blue += (green << 16) | green;
+ red_blue &= 0x00ff00ffu;
+ return (argb & 0xff00ff00u) | red_blue;
+}
+
+static void MaxDiffsForRow(int width, int stride, const uint32_t* const argb,
+ uint8_t* const max_diffs, int used_subtract_green) {
+ uint32_t current, up, down, left, right;
+ int x;
+ if (width <= 2) return;
+ current = argb[0];
+ right = argb[1];
+ if (used_subtract_green) {
+ current = AddGreenToBlueAndRed(current);
+ right = AddGreenToBlueAndRed(right);
+ }
+ // max_diffs[0] and max_diffs[width - 1] are never used.
+ for (x = 1; x < width - 1; ++x) {
+ up = argb[-stride + x];
+ down = argb[stride + x];
+ left = current;
+ current = right;
+ right = argb[x + 1];
+ if (used_subtract_green) {
+ up = AddGreenToBlueAndRed(up);
+ down = AddGreenToBlueAndRed(down);
+ right = AddGreenToBlueAndRed(right);
+ }
+ max_diffs[x] = MaxDiffAroundPixel(current, up, down, left, right);
+ }
+}
+
+// Quantize the difference between the actual component value and its prediction
+// to a multiple of quantization, working modulo 256, taking care not to cross
+// a boundary (inclusive upper limit).
+static uint8_t NearLosslessComponent(uint8_t value, uint8_t predict,
+ uint8_t boundary, int quantization) {
+ const int residual = (value - predict) & 0xff;
+ const int boundary_residual = (boundary - predict) & 0xff;
+ const int lower = residual & ~(quantization - 1);
+ const int upper = lower + quantization;
+ // Resolve ties towards a value closer to the prediction (i.e. towards lower
+ // if value comes after prediction and towards upper otherwise).
+ const int bias = ((boundary - value) & 0xff) < boundary_residual;
+ if (residual - lower < upper - residual + bias) {
+ // lower is closer to residual than upper.
+ if (residual > boundary_residual && lower <= boundary_residual) {
+ // Halve quantization step to avoid crossing boundary. This midpoint is
+ // on the same side of boundary as residual because midpoint >= residual
+ // (since lower is closer than upper) and residual is above the boundary.
+ return lower + (quantization >> 1);
+ }
+ return lower;
+ } else {
+ // upper is closer to residual than lower.
+ if (residual <= boundary_residual && upper > boundary_residual) {
+ // Halve quantization step to avoid crossing boundary. This midpoint is
+ // on the same side of boundary as residual because midpoint <= residual
+ // (since upper is closer than lower) and residual is below the boundary.
+ return lower + (quantization >> 1);
+ }
+ return upper & 0xff;
+ }
+}
+
+static WEBP_INLINE uint8_t NearLosslessDiff(uint8_t a, uint8_t b) {
+ return (uint8_t)((((int)(a) - (int)(b))) & 0xff);
+}
+
+// Quantize every component of the difference between the actual pixel value and
+// its prediction to a multiple of a quantization (a power of 2, not larger than
+// max_quantization which is a power of 2, smaller than max_diff). Take care if
+// value and predict have undergone subtract green, which means that red and
+// blue are represented as offsets from green.
+static uint32_t NearLossless(uint32_t value, uint32_t predict,
+ int max_quantization, int max_diff,
+ int used_subtract_green) {
+ int quantization;
+ uint8_t new_green = 0;
+ uint8_t green_diff = 0;
+ uint8_t a, r, g, b;
+ if (max_diff <= 2) {
+ return VP8LSubPixels(value, predict);
+ }
+ quantization = max_quantization;
+ while (quantization >= max_diff) {
+ quantization >>= 1;
+ }
+ if ((value >> 24) == 0 || (value >> 24) == 0xff) {
+ // Preserve transparency of fully transparent or fully opaque pixels.
+ a = NearLosslessDiff((value >> 24) & 0xff, (predict >> 24) & 0xff);
+ } else {
+ a = NearLosslessComponent(value >> 24, predict >> 24, 0xff, quantization);
+ }
+ g = NearLosslessComponent((value >> 8) & 0xff, (predict >> 8) & 0xff, 0xff,
+ quantization);
+ if (used_subtract_green) {
+ // The green offset will be added to red and blue components during decoding
+ // to obtain the actual red and blue values.
+ new_green = ((predict >> 8) + g) & 0xff;
+ // The amount by which green has been adjusted during quantization. It is
+ // subtracted from red and blue for compensation, to avoid accumulating two
+ // quantization errors in them.
+ green_diff = NearLosslessDiff(new_green, (value >> 8) & 0xff);
+ }
+ r = NearLosslessComponent(NearLosslessDiff((value >> 16) & 0xff, green_diff),
+ (predict >> 16) & 0xff, 0xff - new_green,
+ quantization);
+ b = NearLosslessComponent(NearLosslessDiff(value & 0xff, green_diff),
+ predict & 0xff, 0xff - new_green, quantization);
+ return ((uint32_t)a << 24) | ((uint32_t)r << 16) | ((uint32_t)g << 8) | b;
+}
+#endif // (WEBP_NEAR_LOSSLESS == 1)
+
+// Stores the difference between the pixel and its prediction in "out".
+// In case of a lossy encoding, updates the source image to avoid propagating
+// the deviation further to pixels which depend on the current pixel for their
+// predictions.
+static WEBP_INLINE void GetResidual(
+ int width, int height, uint32_t* const upper_row,
+ uint32_t* const current_row, const uint8_t* const max_diffs, int mode,
+ int x_start, int x_end, int y, int max_quantization, int exact,
+ int used_subtract_green, uint32_t* const out) {
+ if (exact) {
+ PredictBatch(mode, x_start, y, x_end - x_start, current_row, upper_row,
+ out);
+ } else {
+ const VP8LPredictorFunc pred_func = VP8LPredictors[mode];
+ int x;
+ for (x = x_start; x < x_end; ++x) {
+ uint32_t predict;
+ uint32_t residual;
+ if (y == 0) {
+ predict = (x == 0) ? ARGB_BLACK : current_row[x - 1]; // Left.
+ } else if (x == 0) {
+ predict = upper_row[x]; // Top.
+ } else {
+ predict = pred_func(&current_row[x - 1], upper_row + x);
+ }
+#if (WEBP_NEAR_LOSSLESS == 1)
+ if (max_quantization == 1 || mode == 0 || y == 0 || y == height - 1 ||
+ x == 0 || x == width - 1) {
+ residual = VP8LSubPixels(current_row[x], predict);
+ } else {
+ residual = NearLossless(current_row[x], predict, max_quantization,
+ max_diffs[x], used_subtract_green);
+ // Update the source image.
+ current_row[x] = VP8LAddPixels(predict, residual);
+ // x is never 0 here so we do not need to update upper_row like below.
+ }
+#else
+ (void)max_diffs;
+ (void)height;
+ (void)max_quantization;
+ (void)used_subtract_green;
+ residual = VP8LSubPixels(current_row[x], predict);
+#endif
+ if ((current_row[x] & kMaskAlpha) == 0) {
+ // If alpha is 0, cleanup RGB. We can choose the RGB values of the
+ // residual for best compression. The prediction of alpha itself can be
+ // non-zero and must be kept though. We choose RGB of the residual to be
+ // 0.
+ residual &= kMaskAlpha;
+ // Update the source image.
+ current_row[x] = predict & ~kMaskAlpha;
+ // The prediction for the rightmost pixel in a row uses the leftmost
+ // pixel
+ // in that row as its top-right context pixel. Hence if we change the
+ // leftmost pixel of current_row, the corresponding change must be
+ // applied
+ // to upper_row as well where top-right context is being read from.
+ if (x == 0 && y != 0) upper_row[width] = current_row[0];
+ }
+ out[x - x_start] = residual;
+ }
+ }
+}
+
+// Returns best predictor and updates the accumulated histogram.
+// If max_quantization > 1, assumes that near lossless processing will be
+// applied, quantizing residuals to multiples of quantization levels up to
+// max_quantization (the actual quantization level depends on smoothness near
+// the given pixel).
+static int GetBestPredictorForTile(int width, int height,
+ int tile_x, int tile_y, int bits,
+ int accumulated[4][256],
+ uint32_t* const argb_scratch,
+ const uint32_t* const argb,
+ int max_quantization,
+ int exact, int used_subtract_green,
+ const uint32_t* const modes) {
+ const int kNumPredModes = 14;
+ const int start_x = tile_x << bits;
+ const int start_y = tile_y << bits;
+ const int tile_size = 1 << bits;
+ const int max_y = GetMin(tile_size, height - start_y);
+ const int max_x = GetMin(tile_size, width - start_x);
+ // Whether there exist columns just outside the tile.
+ const int have_left = (start_x > 0);
+ // Position and size of the strip covering the tile and adjacent columns if
+ // they exist.
+ const int context_start_x = start_x - have_left;
+#if (WEBP_NEAR_LOSSLESS == 1)
+ const int context_width = max_x + have_left + (max_x < width - start_x);
+#endif
+ const int tiles_per_row = VP8LSubSampleSize(width, bits);
+ // Prediction modes of the left and above neighbor tiles.
+ const int left_mode = (tile_x > 0) ?
+ (modes[tile_y * tiles_per_row + tile_x - 1] >> 8) & 0xff : 0xff;
+ const int above_mode = (tile_y > 0) ?
+ (modes[(tile_y - 1) * tiles_per_row + tile_x] >> 8) & 0xff : 0xff;
+ // The width of upper_row and current_row is one pixel larger than image width
+ // to allow the top right pixel to point to the leftmost pixel of the next row
+ // when at the right edge.
+ uint32_t* upper_row = argb_scratch;
+ uint32_t* current_row = upper_row + width + 1;
+ uint8_t* const max_diffs = (uint8_t*)(current_row + width + 1);
+ float best_diff = MAX_DIFF_COST;
+ int best_mode = 0;
+ int mode;
+ int histo_stack_1[4][256];
+ int histo_stack_2[4][256];
+ // Need pointers to be able to swap arrays.
+ int (*histo_argb)[256] = histo_stack_1;
+ int (*best_histo)[256] = histo_stack_2;
+ int i, j;
+ uint32_t residuals[1 << MAX_TRANSFORM_BITS];
+ assert(bits <= MAX_TRANSFORM_BITS);
+ assert(max_x <= (1 << MAX_TRANSFORM_BITS));
+
+ for (mode = 0; mode < kNumPredModes; ++mode) {
+ float cur_diff;
+ int relative_y;
+ memset(histo_argb, 0, sizeof(histo_stack_1));
+ if (start_y > 0) {
+ // Read the row above the tile which will become the first upper_row.
+ // Include a pixel to the left if it exists; include a pixel to the right
+ // in all cases (wrapping to the leftmost pixel of the next row if it does
+ // not exist).
+ memcpy(current_row + context_start_x,
+ argb + (start_y - 1) * width + context_start_x,
+ sizeof(*argb) * (max_x + have_left + 1));
+ }
+ for (relative_y = 0; relative_y < max_y; ++relative_y) {
+ const int y = start_y + relative_y;
+ int relative_x;
+ uint32_t* tmp = upper_row;
+ upper_row = current_row;
+ current_row = tmp;
+ // Read current_row. Include a pixel to the left if it exists; include a
+ // pixel to the right in all cases except at the bottom right corner of
+ // the image (wrapping to the leftmost pixel of the next row if it does
+ // not exist in the current row).
+ memcpy(current_row + context_start_x,
+ argb + y * width + context_start_x,
+ sizeof(*argb) * (max_x + have_left + (y + 1 < height)));
+#if (WEBP_NEAR_LOSSLESS == 1)
+ if (max_quantization > 1 && y >= 1 && y + 1 < height) {
+ MaxDiffsForRow(context_width, width, argb + y * width + context_start_x,
+ max_diffs + context_start_x, used_subtract_green);
+ }
+#endif
+
+ GetResidual(width, height, upper_row, current_row, max_diffs, mode,
+ start_x, start_x + max_x, y, max_quantization, exact,
+ used_subtract_green, residuals);
+ for (relative_x = 0; relative_x < max_x; ++relative_x) {
+ UpdateHisto(histo_argb, residuals[relative_x]);
+ }
+ }
+ cur_diff = PredictionCostSpatialHistogram(
+ (const int (*)[256])accumulated, (const int (*)[256])histo_argb);
+ // Favor keeping the areas locally similar.
+ if (mode == left_mode) cur_diff -= kSpatialPredictorBias;
+ if (mode == above_mode) cur_diff -= kSpatialPredictorBias;
+
+ if (cur_diff < best_diff) {
+ int (*tmp)[256] = histo_argb;
+ histo_argb = best_histo;
+ best_histo = tmp;
+ best_diff = cur_diff;
+ best_mode = mode;
+ }
+ }
+
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 256; j++) {
+ accumulated[i][j] += best_histo[i][j];
+ }
+ }
+
+ return best_mode;
+}
+
+// Converts pixels of the image to residuals with respect to predictions.
+// If max_quantization > 1, applies near lossless processing, quantizing
+// residuals to multiples of quantization levels up to max_quantization
+// (the actual quantization level depends on smoothness near the given pixel).
+static void CopyImageWithPrediction(int width, int height,
+ int bits, uint32_t* const modes,
+ uint32_t* const argb_scratch,
+ uint32_t* const argb,
+ int low_effort, int max_quantization,
+ int exact, int used_subtract_green) {
+ const int tiles_per_row = VP8LSubSampleSize(width, bits);
+ // The width of upper_row and current_row is one pixel larger than image width
+ // to allow the top right pixel to point to the leftmost pixel of the next row
+ // when at the right edge.
+ uint32_t* upper_row = argb_scratch;
+ uint32_t* current_row = upper_row + width + 1;
+ uint8_t* current_max_diffs = (uint8_t*)(current_row + width + 1);
+#if (WEBP_NEAR_LOSSLESS == 1)
+ uint8_t* lower_max_diffs = current_max_diffs + width;
+#endif
+ int y;
+
+ for (y = 0; y < height; ++y) {
+ int x;
+ uint32_t* const tmp32 = upper_row;
+ upper_row = current_row;
+ current_row = tmp32;
+ memcpy(current_row, argb + y * width,
+ sizeof(*argb) * (width + (y + 1 < height)));
+
+ if (low_effort) {
+ PredictBatch(kPredLowEffort, 0, y, width, current_row, upper_row,
+ argb + y * width);
+ } else {
+#if (WEBP_NEAR_LOSSLESS == 1)
+ if (max_quantization > 1) {
+ // Compute max_diffs for the lower row now, because that needs the
+ // contents of argb for the current row, which we will overwrite with
+ // residuals before proceeding with the next row.
+ uint8_t* const tmp8 = current_max_diffs;
+ current_max_diffs = lower_max_diffs;
+ lower_max_diffs = tmp8;
+ if (y + 2 < height) {
+ MaxDiffsForRow(width, width, argb + (y + 1) * width, lower_max_diffs,
+ used_subtract_green);
+ }
+ }
+#endif
+ for (x = 0; x < width;) {
+ const int mode =
+ (modes[(y >> bits) * tiles_per_row + (x >> bits)] >> 8) & 0xff;
+ int x_end = x + (1 << bits);
+ if (x_end > width) x_end = width;
+ GetResidual(width, height, upper_row, current_row, current_max_diffs,
+ mode, x, x_end, y, max_quantization, exact,
+ used_subtract_green, argb + y * width + x);
+ x = x_end;
+ }
+ }
+ }
+}
+
+// Finds the best predictor for each tile, and converts the image to residuals
+// with respect to predictions. If near_lossless_quality < 100, applies
+// near lossless processing, shaving off more bits of residuals for lower
+// qualities.
+int VP8LResidualImage(int width, int height, int bits, int low_effort,
+ uint32_t* const argb, uint32_t* const argb_scratch,
+ uint32_t* const image, int near_lossless_quality,
+ int exact, int used_subtract_green,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent) {
+ const int tiles_per_row = VP8LSubSampleSize(width, bits);
+ const int tiles_per_col = VP8LSubSampleSize(height, bits);
+ int percent_start = *percent;
+ int tile_y;
+ int histo[4][256];
+ const int max_quantization = 1 << VP8LNearLosslessBits(near_lossless_quality);
+ if (low_effort) {
+ int i;
+ for (i = 0; i < tiles_per_row * tiles_per_col; ++i) {
+ image[i] = ARGB_BLACK | (kPredLowEffort << 8);
+ }
+ } else {
+ memset(histo, 0, sizeof(histo));
+ for (tile_y = 0; tile_y < tiles_per_col; ++tile_y) {
+ int tile_x;
+ for (tile_x = 0; tile_x < tiles_per_row; ++tile_x) {
+ const int pred = GetBestPredictorForTile(
+ width, height, tile_x, tile_y, bits, histo, argb_scratch, argb,
+ max_quantization, exact, used_subtract_green, image);
+ image[tile_y * tiles_per_row + tile_x] = ARGB_BLACK | (pred << 8);
+ }
+
+ if (!WebPReportProgress(
+ pic, percent_start + percent_range * tile_y / tiles_per_col,
+ percent)) {
+ return 0;
+ }
+ }
+ }
+
+ CopyImageWithPrediction(width, height, bits, image, argb_scratch, argb,
+ low_effort, max_quantization, exact,
+ used_subtract_green);
+ return WebPReportProgress(pic, percent_start + percent_range, percent);
+}
+
+//------------------------------------------------------------------------------
+// Color transform functions.
+
+static WEBP_INLINE void MultipliersClear(VP8LMultipliers* const m) {
+ m->green_to_red_ = 0;
+ m->green_to_blue_ = 0;
+ m->red_to_blue_ = 0;
+}
+
+static WEBP_INLINE void ColorCodeToMultipliers(uint32_t color_code,
+ VP8LMultipliers* const m) {
+ m->green_to_red_ = (color_code >> 0) & 0xff;
+ m->green_to_blue_ = (color_code >> 8) & 0xff;
+ m->red_to_blue_ = (color_code >> 16) & 0xff;
+}
+
+static WEBP_INLINE uint32_t MultipliersToColorCode(
+ const VP8LMultipliers* const m) {
+ return 0xff000000u |
+ ((uint32_t)(m->red_to_blue_) << 16) |
+ ((uint32_t)(m->green_to_blue_) << 8) |
+ m->green_to_red_;
+}
+
+static float PredictionCostCrossColor(const int accumulated[256],
+ const int counts[256]) {
+ // Favor low entropy, locally and globally.
+ // Favor small absolute values for PredictionCostSpatial
+ static const float kExpValue = 2.4f;
+ return VP8LCombinedShannonEntropy(counts, accumulated) +
+ PredictionCostSpatial(counts, 3, kExpValue);
+}
+
+static float GetPredictionCostCrossColorRed(
+ const uint32_t* argb, int stride, int tile_width, int tile_height,
+ VP8LMultipliers prev_x, VP8LMultipliers prev_y, int green_to_red,
+ const int accumulated_red_histo[256]) {
+ int histo[256] = { 0 };
+ float cur_diff;
+
+ VP8LCollectColorRedTransforms(argb, stride, tile_width, tile_height,
+ green_to_red, histo);
+
+ cur_diff = PredictionCostCrossColor(accumulated_red_histo, histo);
+ if ((uint8_t)green_to_red == prev_x.green_to_red_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)green_to_red == prev_y.green_to_red_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if (green_to_red == 0) {
+ cur_diff -= 3;
+ }
+ return cur_diff;
+}
+
+static void GetBestGreenToRed(
+ const uint32_t* argb, int stride, int tile_width, int tile_height,
+ VP8LMultipliers prev_x, VP8LMultipliers prev_y, int quality,
+ const int accumulated_red_histo[256], VP8LMultipliers* const best_tx) {
+ const int kMaxIters = 4 + ((7 * quality) >> 8); // in range [4..6]
+ int green_to_red_best = 0;
+ int iter, offset;
+ float best_diff = GetPredictionCostCrossColorRed(
+ argb, stride, tile_width, tile_height, prev_x, prev_y,
+ green_to_red_best, accumulated_red_histo);
+ for (iter = 0; iter < kMaxIters; ++iter) {
+ // ColorTransformDelta is a 3.5 bit fixed point, so 32 is equal to
+ // one in color computation. Having initial delta here as 1 is sufficient
+ // to explore the range of (-2, 2).
+ const int delta = 32 >> iter;
+ // Try a negative and a positive delta from the best known value.
+ for (offset = -delta; offset <= delta; offset += 2 * delta) {
+ const int green_to_red_cur = offset + green_to_red_best;
+ const float cur_diff = GetPredictionCostCrossColorRed(
+ argb, stride, tile_width, tile_height, prev_x, prev_y,
+ green_to_red_cur, accumulated_red_histo);
+ if (cur_diff < best_diff) {
+ best_diff = cur_diff;
+ green_to_red_best = green_to_red_cur;
+ }
+ }
+ }
+ best_tx->green_to_red_ = (green_to_red_best & 0xff);
+}
+
+static float GetPredictionCostCrossColorBlue(
+ const uint32_t* argb, int stride, int tile_width, int tile_height,
+ VP8LMultipliers prev_x, VP8LMultipliers prev_y,
+ int green_to_blue, int red_to_blue, const int accumulated_blue_histo[256]) {
+ int histo[256] = { 0 };
+ float cur_diff;
+
+ VP8LCollectColorBlueTransforms(argb, stride, tile_width, tile_height,
+ green_to_blue, red_to_blue, histo);
+
+ cur_diff = PredictionCostCrossColor(accumulated_blue_histo, histo);
+ if ((uint8_t)green_to_blue == prev_x.green_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)green_to_blue == prev_y.green_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)red_to_blue == prev_x.red_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)red_to_blue == prev_y.red_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if (green_to_blue == 0) {
+ cur_diff -= 3;
+ }
+ if (red_to_blue == 0) {
+ cur_diff -= 3;
+ }
+ return cur_diff;
+}
+
+#define kGreenRedToBlueNumAxis 8
+#define kGreenRedToBlueMaxIters 7
+static void GetBestGreenRedToBlue(
+ const uint32_t* argb, int stride, int tile_width, int tile_height,
+ VP8LMultipliers prev_x, VP8LMultipliers prev_y, int quality,
+ const int accumulated_blue_histo[256],
+ VP8LMultipliers* const best_tx) {
+ const int8_t offset[kGreenRedToBlueNumAxis][2] =
+ {{0, -1}, {0, 1}, {-1, 0}, {1, 0}, {-1, -1}, {-1, 1}, {1, -1}, {1, 1}};
+ const int8_t delta_lut[kGreenRedToBlueMaxIters] = { 16, 16, 8, 4, 2, 2, 2 };
+ const int iters =
+ (quality < 25) ? 1 : (quality > 50) ? kGreenRedToBlueMaxIters : 4;
+ int green_to_blue_best = 0;
+ int red_to_blue_best = 0;
+ int iter;
+ // Initial value at origin:
+ float best_diff = GetPredictionCostCrossColorBlue(
+ argb, stride, tile_width, tile_height, prev_x, prev_y,
+ green_to_blue_best, red_to_blue_best, accumulated_blue_histo);
+ for (iter = 0; iter < iters; ++iter) {
+ const int delta = delta_lut[iter];
+ int axis;
+ for (axis = 0; axis < kGreenRedToBlueNumAxis; ++axis) {
+ const int green_to_blue_cur =
+ offset[axis][0] * delta + green_to_blue_best;
+ const int red_to_blue_cur = offset[axis][1] * delta + red_to_blue_best;
+ const float cur_diff = GetPredictionCostCrossColorBlue(
+ argb, stride, tile_width, tile_height, prev_x, prev_y,
+ green_to_blue_cur, red_to_blue_cur, accumulated_blue_histo);
+ if (cur_diff < best_diff) {
+ best_diff = cur_diff;
+ green_to_blue_best = green_to_blue_cur;
+ red_to_blue_best = red_to_blue_cur;
+ }
+ if (quality < 25 && iter == 4) {
+ // Only axis aligned diffs for lower quality.
+ break; // next iter.
+ }
+ }
+ if (delta == 2 && green_to_blue_best == 0 && red_to_blue_best == 0) {
+ // Further iterations would not help.
+ break; // out of iter-loop.
+ }
+ }
+ best_tx->green_to_blue_ = green_to_blue_best & 0xff;
+ best_tx->red_to_blue_ = red_to_blue_best & 0xff;
+}
+#undef kGreenRedToBlueMaxIters
+#undef kGreenRedToBlueNumAxis
+
+static VP8LMultipliers GetBestColorTransformForTile(
+ int tile_x, int tile_y, int bits,
+ VP8LMultipliers prev_x,
+ VP8LMultipliers prev_y,
+ int quality, int xsize, int ysize,
+ const int accumulated_red_histo[256],
+ const int accumulated_blue_histo[256],
+ const uint32_t* const argb) {
+ const int max_tile_size = 1 << bits;
+ const int tile_y_offset = tile_y * max_tile_size;
+ const int tile_x_offset = tile_x * max_tile_size;
+ const int all_x_max = GetMin(tile_x_offset + max_tile_size, xsize);
+ const int all_y_max = GetMin(tile_y_offset + max_tile_size, ysize);
+ const int tile_width = all_x_max - tile_x_offset;
+ const int tile_height = all_y_max - tile_y_offset;
+ const uint32_t* const tile_argb = argb + tile_y_offset * xsize
+ + tile_x_offset;
+ VP8LMultipliers best_tx;
+ MultipliersClear(&best_tx);
+
+ GetBestGreenToRed(tile_argb, xsize, tile_width, tile_height,
+ prev_x, prev_y, quality, accumulated_red_histo, &best_tx);
+ GetBestGreenRedToBlue(tile_argb, xsize, tile_width, tile_height,
+ prev_x, prev_y, quality, accumulated_blue_histo,
+ &best_tx);
+ return best_tx;
+}
+
+static void CopyTileWithColorTransform(int xsize, int ysize,
+ int tile_x, int tile_y,
+ int max_tile_size,
+ VP8LMultipliers color_transform,
+ uint32_t* argb) {
+ const int xscan = GetMin(max_tile_size, xsize - tile_x);
+ int yscan = GetMin(max_tile_size, ysize - tile_y);
+ argb += tile_y * xsize + tile_x;
+ while (yscan-- > 0) {
+ VP8LTransformColor(&color_transform, argb, xscan);
+ argb += xsize;
+ }
+}
+
+int VP8LColorSpaceTransform(int width, int height, int bits, int quality,
+ uint32_t* const argb, uint32_t* image,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent) {
+ const int max_tile_size = 1 << bits;
+ const int tile_xsize = VP8LSubSampleSize(width, bits);
+ const int tile_ysize = VP8LSubSampleSize(height, bits);
+ int percent_start = *percent;
+ int accumulated_red_histo[256] = { 0 };
+ int accumulated_blue_histo[256] = { 0 };
+ int tile_x, tile_y;
+ VP8LMultipliers prev_x, prev_y;
+ MultipliersClear(&prev_y);
+ MultipliersClear(&prev_x);
+ for (tile_y = 0; tile_y < tile_ysize; ++tile_y) {
+ for (tile_x = 0; tile_x < tile_xsize; ++tile_x) {
+ int y;
+ const int tile_x_offset = tile_x * max_tile_size;
+ const int tile_y_offset = tile_y * max_tile_size;
+ const int all_x_max = GetMin(tile_x_offset + max_tile_size, width);
+ const int all_y_max = GetMin(tile_y_offset + max_tile_size, height);
+ const int offset = tile_y * tile_xsize + tile_x;
+ if (tile_y != 0) {
+ ColorCodeToMultipliers(image[offset - tile_xsize], &prev_y);
+ }
+ prev_x = GetBestColorTransformForTile(tile_x, tile_y, bits,
+ prev_x, prev_y,
+ quality, width, height,
+ accumulated_red_histo,
+ accumulated_blue_histo,
+ argb);
+ image[offset] = MultipliersToColorCode(&prev_x);
+ CopyTileWithColorTransform(width, height, tile_x_offset, tile_y_offset,
+ max_tile_size, prev_x, argb);
+
+ // Gather accumulated histogram data.
+ for (y = tile_y_offset; y < all_y_max; ++y) {
+ int ix = y * width + tile_x_offset;
+ const int ix_end = ix + all_x_max - tile_x_offset;
+ for (; ix < ix_end; ++ix) {
+ const uint32_t pix = argb[ix];
+ if (ix >= 2 &&
+ pix == argb[ix - 2] &&
+ pix == argb[ix - 1]) {
+ continue; // repeated pixels are handled by backward references
+ }
+ if (ix >= width + 2 &&
+ argb[ix - 2] == argb[ix - width - 2] &&
+ argb[ix - 1] == argb[ix - width - 1] &&
+ pix == argb[ix - width]) {
+ continue; // repeated pixels are handled by backward references
+ }
+ ++accumulated_red_histo[(pix >> 16) & 0xff];
+ ++accumulated_blue_histo[(pix >> 0) & 0xff];
+ }
+ }
+ }
+ if (!WebPReportProgress(
+ pic, percent_start + percent_range * tile_y / tile_ysize,
+ percent)) {
+ return 0;
+ }
+ }
+ return 1;
+}
diff --git a/media/libwebp/src/enc/quant_enc.c b/media/libwebp/src/enc/quant_enc.c
new file mode 100644
index 0000000000..6d8202d277
--- /dev/null
+++ b/media/libwebp/src/enc/quant_enc.c
@@ -0,0 +1,1398 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Quantization
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <math.h>
+#include <stdlib.h> // for abs()
+
+#include "src/dsp/quant.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/enc/cost_enc.h"
+
+#define DO_TRELLIS_I4 1
+#define DO_TRELLIS_I16 1 // not a huge gain, but ok at low bitrate.
+#define DO_TRELLIS_UV 0 // disable trellis for UV. Risky. Not worth.
+#define USE_TDISTO 1
+
+#define MID_ALPHA 64 // neutral value for susceptibility
+#define MIN_ALPHA 30 // lowest usable value for susceptibility
+#define MAX_ALPHA 100 // higher meaningful value for susceptibility
+
+#define SNS_TO_DQ 0.9 // Scaling constant between the sns value and the QP
+ // power-law modulation. Must be strictly less than 1.
+
+// number of non-zero coeffs below which we consider the block very flat
+// (and apply a penalty to complex predictions)
+#define FLATNESS_LIMIT_I16 0 // I16 mode (special case)
+#define FLATNESS_LIMIT_I4 3 // I4 mode
+#define FLATNESS_LIMIT_UV 2 // UV mode
+#define FLATNESS_PENALTY 140 // roughly ~1bit per block
+
+#define MULT_8B(a, b) (((a) * (b) + 128) >> 8)
+
+#define RD_DISTO_MULT 256 // distortion multiplier (equivalent of lambda)
+
+// #define DEBUG_BLOCK
+
+//------------------------------------------------------------------------------
+
+#if defined(DEBUG_BLOCK)
+
+#include <stdio.h>
+#include <stdlib.h>
+
+static void PrintBlockInfo(const VP8EncIterator* const it,
+ const VP8ModeScore* const rd) {
+ int i, j;
+ const int is_i16 = (it->mb_->type_ == 1);
+ const uint8_t* const y_in = it->yuv_in_ + Y_OFF_ENC;
+ const uint8_t* const y_out = it->yuv_out_ + Y_OFF_ENC;
+ const uint8_t* const uv_in = it->yuv_in_ + U_OFF_ENC;
+ const uint8_t* const uv_out = it->yuv_out_ + U_OFF_ENC;
+ printf("SOURCE / OUTPUT / ABS DELTA\n");
+ for (j = 0; j < 16; ++j) {
+ for (i = 0; i < 16; ++i) printf("%3d ", y_in[i + j * BPS]);
+ printf(" ");
+ for (i = 0; i < 16; ++i) printf("%3d ", y_out[i + j * BPS]);
+ printf(" ");
+ for (i = 0; i < 16; ++i) {
+ printf("%1d ", abs(y_in[i + j * BPS] - y_out[i + j * BPS]));
+ }
+ printf("\n");
+ }
+ printf("\n"); // newline before the U/V block
+ for (j = 0; j < 8; ++j) {
+ for (i = 0; i < 8; ++i) printf("%3d ", uv_in[i + j * BPS]);
+ printf(" ");
+ for (i = 8; i < 16; ++i) printf("%3d ", uv_in[i + j * BPS]);
+ printf(" ");
+ for (i = 0; i < 8; ++i) printf("%3d ", uv_out[i + j * BPS]);
+ printf(" ");
+ for (i = 8; i < 16; ++i) printf("%3d ", uv_out[i + j * BPS]);
+ printf(" ");
+ for (i = 0; i < 8; ++i) {
+ printf("%1d ", abs(uv_out[i + j * BPS] - uv_in[i + j * BPS]));
+ }
+ printf(" ");
+ for (i = 8; i < 16; ++i) {
+ printf("%1d ", abs(uv_out[i + j * BPS] - uv_in[i + j * BPS]));
+ }
+ printf("\n");
+ }
+ printf("\nD:%d SD:%d R:%d H:%d nz:0x%x score:%d\n",
+ (int)rd->D, (int)rd->SD, (int)rd->R, (int)rd->H, (int)rd->nz,
+ (int)rd->score);
+ if (is_i16) {
+ printf("Mode: %d\n", rd->mode_i16);
+ printf("y_dc_levels:");
+ for (i = 0; i < 16; ++i) printf("%3d ", rd->y_dc_levels[i]);
+ printf("\n");
+ } else {
+ printf("Modes[16]: ");
+ for (i = 0; i < 16; ++i) printf("%d ", rd->modes_i4[i]);
+ printf("\n");
+ }
+ printf("y_ac_levels:\n");
+ for (j = 0; j < 16; ++j) {
+ for (i = is_i16 ? 1 : 0; i < 16; ++i) {
+ printf("%4d ", rd->y_ac_levels[j][i]);
+ }
+ printf("\n");
+ }
+ printf("\n");
+ printf("uv_levels (mode=%d):\n", rd->mode_uv);
+ for (j = 0; j < 8; ++j) {
+ for (i = 0; i < 16; ++i) {
+ printf("%4d ", rd->uv_levels[j][i]);
+ }
+ printf("\n");
+ }
+}
+
+#endif // DEBUG_BLOCK
+
+//------------------------------------------------------------------------------
+
+static WEBP_INLINE int clip(int v, int m, int M) {
+ return v < m ? m : v > M ? M : v;
+}
+
+static const uint8_t kZigzag[16] = {
+ 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15
+};
+
+static const uint8_t kDcTable[128] = {
+ 4, 5, 6, 7, 8, 9, 10, 10,
+ 11, 12, 13, 14, 15, 16, 17, 17,
+ 18, 19, 20, 20, 21, 21, 22, 22,
+ 23, 23, 24, 25, 25, 26, 27, 28,
+ 29, 30, 31, 32, 33, 34, 35, 36,
+ 37, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 46, 47, 48, 49, 50,
+ 51, 52, 53, 54, 55, 56, 57, 58,
+ 59, 60, 61, 62, 63, 64, 65, 66,
+ 67, 68, 69, 70, 71, 72, 73, 74,
+ 75, 76, 76, 77, 78, 79, 80, 81,
+ 82, 83, 84, 85, 86, 87, 88, 89,
+ 91, 93, 95, 96, 98, 100, 101, 102,
+ 104, 106, 108, 110, 112, 114, 116, 118,
+ 122, 124, 126, 128, 130, 132, 134, 136,
+ 138, 140, 143, 145, 148, 151, 154, 157
+};
+
+static const uint16_t kAcTable[128] = {
+ 4, 5, 6, 7, 8, 9, 10, 11,
+ 12, 13, 14, 15, 16, 17, 18, 19,
+ 20, 21, 22, 23, 24, 25, 26, 27,
+ 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 47, 48, 49, 50, 51,
+ 52, 53, 54, 55, 56, 57, 58, 60,
+ 62, 64, 66, 68, 70, 72, 74, 76,
+ 78, 80, 82, 84, 86, 88, 90, 92,
+ 94, 96, 98, 100, 102, 104, 106, 108,
+ 110, 112, 114, 116, 119, 122, 125, 128,
+ 131, 134, 137, 140, 143, 146, 149, 152,
+ 155, 158, 161, 164, 167, 170, 173, 177,
+ 181, 185, 189, 193, 197, 201, 205, 209,
+ 213, 217, 221, 225, 229, 234, 239, 245,
+ 249, 254, 259, 264, 269, 274, 279, 284
+};
+
+static const uint16_t kAcTable2[128] = {
+ 8, 8, 9, 10, 12, 13, 15, 17,
+ 18, 20, 21, 23, 24, 26, 27, 29,
+ 31, 32, 34, 35, 37, 38, 40, 41,
+ 43, 44, 46, 48, 49, 51, 52, 54,
+ 55, 57, 58, 60, 62, 63, 65, 66,
+ 68, 69, 71, 72, 74, 75, 77, 79,
+ 80, 82, 83, 85, 86, 88, 89, 93,
+ 96, 99, 102, 105, 108, 111, 114, 117,
+ 120, 124, 127, 130, 133, 136, 139, 142,
+ 145, 148, 151, 155, 158, 161, 164, 167,
+ 170, 173, 176, 179, 184, 189, 193, 198,
+ 203, 207, 212, 217, 221, 226, 230, 235,
+ 240, 244, 249, 254, 258, 263, 268, 274,
+ 280, 286, 292, 299, 305, 311, 317, 323,
+ 330, 336, 342, 348, 354, 362, 370, 379,
+ 385, 393, 401, 409, 416, 424, 432, 440
+};
+
+static const uint8_t kBiasMatrices[3][2] = { // [luma-ac,luma-dc,chroma][dc,ac]
+ { 96, 110 }, { 96, 108 }, { 110, 115 }
+};
+
+// Sharpening by (slightly) raising the hi-frequency coeffs.
+// Hack-ish but helpful for mid-bitrate range. Use with care.
+#define SHARPEN_BITS 11 // number of descaling bits for sharpening bias
+static const uint8_t kFreqSharpening[16] = {
+ 0, 30, 60, 90,
+ 30, 60, 90, 90,
+ 60, 90, 90, 90,
+ 90, 90, 90, 90
+};
+
+//------------------------------------------------------------------------------
+// Initialize quantization parameters in VP8Matrix
+
+// Returns the average quantizer
+static int ExpandMatrix(VP8Matrix* const m, int type) {
+ int i, sum;
+ for (i = 0; i < 2; ++i) {
+ const int is_ac_coeff = (i > 0);
+ const int bias = kBiasMatrices[type][is_ac_coeff];
+ m->iq_[i] = (1 << QFIX) / m->q_[i];
+ m->bias_[i] = BIAS(bias);
+ // zthresh_ is the exact value such that QUANTDIV(coeff, iQ, B) is:
+ // * zero if coeff <= zthresh
+ // * non-zero if coeff > zthresh
+ m->zthresh_[i] = ((1 << QFIX) - 1 - m->bias_[i]) / m->iq_[i];
+ }
+ for (i = 2; i < 16; ++i) {
+ m->q_[i] = m->q_[1];
+ m->iq_[i] = m->iq_[1];
+ m->bias_[i] = m->bias_[1];
+ m->zthresh_[i] = m->zthresh_[1];
+ }
+ for (sum = 0, i = 0; i < 16; ++i) {
+ if (type == 0) { // we only use sharpening for AC luma coeffs
+ m->sharpen_[i] = (kFreqSharpening[i] * m->q_[i]) >> SHARPEN_BITS;
+ } else {
+ m->sharpen_[i] = 0;
+ }
+ sum += m->q_[i];
+ }
+ return (sum + 8) >> 4;
+}
+
+static void CheckLambdaValue(int* const v) { if (*v < 1) *v = 1; }
+
+static void SetupMatrices(VP8Encoder* enc) {
+ int i;
+ const int tlambda_scale =
+ (enc->method_ >= 4) ? enc->config_->sns_strength
+ : 0;
+ const int num_segments = enc->segment_hdr_.num_segments_;
+ for (i = 0; i < num_segments; ++i) {
+ VP8SegmentInfo* const m = &enc->dqm_[i];
+ const int q = m->quant_;
+ int q_i4, q_i16, q_uv;
+ m->y1_.q_[0] = kDcTable[clip(q + enc->dq_y1_dc_, 0, 127)];
+ m->y1_.q_[1] = kAcTable[clip(q, 0, 127)];
+
+ m->y2_.q_[0] = kDcTable[ clip(q + enc->dq_y2_dc_, 0, 127)] * 2;
+ m->y2_.q_[1] = kAcTable2[clip(q + enc->dq_y2_ac_, 0, 127)];
+
+ m->uv_.q_[0] = kDcTable[clip(q + enc->dq_uv_dc_, 0, 117)];
+ m->uv_.q_[1] = kAcTable[clip(q + enc->dq_uv_ac_, 0, 127)];
+
+ q_i4 = ExpandMatrix(&m->y1_, 0);
+ q_i16 = ExpandMatrix(&m->y2_, 1);
+ q_uv = ExpandMatrix(&m->uv_, 2);
+
+ m->lambda_i4_ = (3 * q_i4 * q_i4) >> 7;
+ m->lambda_i16_ = (3 * q_i16 * q_i16);
+ m->lambda_uv_ = (3 * q_uv * q_uv) >> 6;
+ m->lambda_mode_ = (1 * q_i4 * q_i4) >> 7;
+ m->lambda_trellis_i4_ = (7 * q_i4 * q_i4) >> 3;
+ m->lambda_trellis_i16_ = (q_i16 * q_i16) >> 2;
+ m->lambda_trellis_uv_ = (q_uv * q_uv) << 1;
+ m->tlambda_ = (tlambda_scale * q_i4) >> 5;
+
+ // none of these constants should be < 1
+ CheckLambdaValue(&m->lambda_i4_);
+ CheckLambdaValue(&m->lambda_i16_);
+ CheckLambdaValue(&m->lambda_uv_);
+ CheckLambdaValue(&m->lambda_mode_);
+ CheckLambdaValue(&m->lambda_trellis_i4_);
+ CheckLambdaValue(&m->lambda_trellis_i16_);
+ CheckLambdaValue(&m->lambda_trellis_uv_);
+ CheckLambdaValue(&m->tlambda_);
+
+ m->min_disto_ = 20 * m->y1_.q_[0]; // quantization-aware min disto
+ m->max_edge_ = 0;
+
+ m->i4_penalty_ = 1000 * q_i4 * q_i4;
+ }
+}
+
+//------------------------------------------------------------------------------
+// Initialize filtering parameters
+
+// Very small filter-strength values have close to no visual effect. So we can
+// save a little decoding-CPU by turning filtering off for these.
+#define FSTRENGTH_CUTOFF 2
+
+static void SetupFilterStrength(VP8Encoder* const enc) {
+ int i;
+ // level0 is in [0..500]. Using '-f 50' as filter_strength is mid-filtering.
+ const int level0 = 5 * enc->config_->filter_strength;
+ for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
+ VP8SegmentInfo* const m = &enc->dqm_[i];
+ // We focus on the quantization of AC coeffs.
+ const int qstep = kAcTable[clip(m->quant_, 0, 127)] >> 2;
+ const int base_strength =
+ VP8FilterStrengthFromDelta(enc->filter_hdr_.sharpness_, qstep);
+ // Segments with lower complexity ('beta') will be less filtered.
+ const int f = base_strength * level0 / (256 + m->beta_);
+ m->fstrength_ = (f < FSTRENGTH_CUTOFF) ? 0 : (f > 63) ? 63 : f;
+ }
+ // We record the initial strength (mainly for the case of 1-segment only).
+ enc->filter_hdr_.level_ = enc->dqm_[0].fstrength_;
+ enc->filter_hdr_.simple_ = (enc->config_->filter_type == 0);
+ enc->filter_hdr_.sharpness_ = enc->config_->filter_sharpness;
+}
+
+//------------------------------------------------------------------------------
+
+// Note: if you change the values below, remember that the max range
+// allowed by the syntax for DQ_UV is [-16,16].
+#define MAX_DQ_UV (6)
+#define MIN_DQ_UV (-4)
+
+// We want to emulate jpeg-like behaviour where the expected "good" quality
+// is around q=75. Internally, our "good" middle is around c=50. So we
+// map accordingly using linear piece-wise function
+static double QualityToCompression(double c) {
+ const double linear_c = (c < 0.75) ? c * (2. / 3.) : 2. * c - 1.;
+ // The file size roughly scales as pow(quantizer, 3.). Actually, the
+ // exponent is somewhere between 2.8 and 3.2, but we're mostly interested
+ // in the mid-quant range. So we scale the compressibility inversely to
+ // this power-law: quant ~= compression ^ 1/3. This law holds well for
+ // low quant. Finer modeling for high-quant would make use of kAcTable[]
+ // more explicitly.
+ const double v = pow(linear_c, 1 / 3.);
+ return v;
+}
+
+static double QualityToJPEGCompression(double c, double alpha) {
+ // We map the complexity 'alpha' and quality setting 'c' to a compression
+ // exponent empirically matched to the compression curve of libjpeg6b.
+ // On average, the WebP output size will be roughly similar to that of a
+ // JPEG file compressed with same quality factor.
+ const double amin = 0.30;
+ const double amax = 0.85;
+ const double exp_min = 0.4;
+ const double exp_max = 0.9;
+ const double slope = (exp_min - exp_max) / (amax - amin);
+ // Linearly interpolate 'expn' from exp_min to exp_max
+ // in the [amin, amax] range.
+ const double expn = (alpha > amax) ? exp_min
+ : (alpha < amin) ? exp_max
+ : exp_max + slope * (alpha - amin);
+ const double v = pow(c, expn);
+ return v;
+}
+
+static int SegmentsAreEquivalent(const VP8SegmentInfo* const S1,
+ const VP8SegmentInfo* const S2) {
+ return (S1->quant_ == S2->quant_) && (S1->fstrength_ == S2->fstrength_);
+}
+
+static void SimplifySegments(VP8Encoder* const enc) {
+ int map[NUM_MB_SEGMENTS] = { 0, 1, 2, 3 };
+ // 'num_segments_' is previously validated and <= NUM_MB_SEGMENTS, but an
+ // explicit check is needed to avoid a spurious warning about 'i' exceeding
+ // array bounds of 'dqm_' with some compilers (noticed with gcc-4.9).
+ const int num_segments = (enc->segment_hdr_.num_segments_ < NUM_MB_SEGMENTS)
+ ? enc->segment_hdr_.num_segments_
+ : NUM_MB_SEGMENTS;
+ int num_final_segments = 1;
+ int s1, s2;
+ for (s1 = 1; s1 < num_segments; ++s1) { // find similar segments
+ const VP8SegmentInfo* const S1 = &enc->dqm_[s1];
+ int found = 0;
+ // check if we already have similar segment
+ for (s2 = 0; s2 < num_final_segments; ++s2) {
+ const VP8SegmentInfo* const S2 = &enc->dqm_[s2];
+ if (SegmentsAreEquivalent(S1, S2)) {
+ found = 1;
+ break;
+ }
+ }
+ map[s1] = s2;
+ if (!found) {
+ if (num_final_segments != s1) {
+ enc->dqm_[num_final_segments] = enc->dqm_[s1];
+ }
+ ++num_final_segments;
+ }
+ }
+ if (num_final_segments < num_segments) { // Remap
+ int i = enc->mb_w_ * enc->mb_h_;
+ while (i-- > 0) enc->mb_info_[i].segment_ = map[enc->mb_info_[i].segment_];
+ enc->segment_hdr_.num_segments_ = num_final_segments;
+ // Replicate the trailing segment infos (it's mostly cosmetics)
+ for (i = num_final_segments; i < num_segments; ++i) {
+ enc->dqm_[i] = enc->dqm_[num_final_segments - 1];
+ }
+ }
+}
+
+void VP8SetSegmentParams(VP8Encoder* const enc, float quality) {
+ int i;
+ int dq_uv_ac, dq_uv_dc;
+ const int num_segments = enc->segment_hdr_.num_segments_;
+ const double amp = SNS_TO_DQ * enc->config_->sns_strength / 100. / 128.;
+ const double Q = quality / 100.;
+ const double c_base = enc->config_->emulate_jpeg_size ?
+ QualityToJPEGCompression(Q, enc->alpha_ / 255.) :
+ QualityToCompression(Q);
+ for (i = 0; i < num_segments; ++i) {
+ // We modulate the base coefficient to accommodate for the quantization
+ // susceptibility and allow denser segments to be quantized more.
+ const double expn = 1. - amp * enc->dqm_[i].alpha_;
+ const double c = pow(c_base, expn);
+ const int q = (int)(127. * (1. - c));
+ assert(expn > 0.);
+ enc->dqm_[i].quant_ = clip(q, 0, 127);
+ }
+
+ // purely indicative in the bitstream (except for the 1-segment case)
+ enc->base_quant_ = enc->dqm_[0].quant_;
+
+ // fill-in values for the unused segments (required by the syntax)
+ for (i = num_segments; i < NUM_MB_SEGMENTS; ++i) {
+ enc->dqm_[i].quant_ = enc->base_quant_;
+ }
+
+ // uv_alpha_ is normally spread around ~60. The useful range is
+ // typically ~30 (quite bad) to ~100 (ok to decimate UV more).
+ // We map it to the safe maximal range of MAX/MIN_DQ_UV for dq_uv.
+ dq_uv_ac = (enc->uv_alpha_ - MID_ALPHA) * (MAX_DQ_UV - MIN_DQ_UV)
+ / (MAX_ALPHA - MIN_ALPHA);
+ // we rescale by the user-defined strength of adaptation
+ dq_uv_ac = dq_uv_ac * enc->config_->sns_strength / 100;
+ // and make it safe.
+ dq_uv_ac = clip(dq_uv_ac, MIN_DQ_UV, MAX_DQ_UV);
+ // We also boost the dc-uv-quant a little, based on sns-strength, since
+ // U/V channels are quite more reactive to high quants (flat DC-blocks
+ // tend to appear, and are unpleasant).
+ dq_uv_dc = -4 * enc->config_->sns_strength / 100;
+ dq_uv_dc = clip(dq_uv_dc, -15, 15); // 4bit-signed max allowed
+
+ enc->dq_y1_dc_ = 0; // TODO(skal): dq-lum
+ enc->dq_y2_dc_ = 0;
+ enc->dq_y2_ac_ = 0;
+ enc->dq_uv_dc_ = dq_uv_dc;
+ enc->dq_uv_ac_ = dq_uv_ac;
+
+ SetupFilterStrength(enc); // initialize segments' filtering, eventually
+
+ if (num_segments > 1) SimplifySegments(enc);
+
+ SetupMatrices(enc); // finalize quantization matrices
+}
+
+//------------------------------------------------------------------------------
+// Form the predictions in cache
+
+// Must be ordered using {DC_PRED, TM_PRED, V_PRED, H_PRED} as index
+const uint16_t VP8I16ModeOffsets[4] = { I16DC16, I16TM16, I16VE16, I16HE16 };
+const uint16_t VP8UVModeOffsets[4] = { C8DC8, C8TM8, C8VE8, C8HE8 };
+
+// Must be indexed using {B_DC_PRED -> B_HU_PRED} as index
+const uint16_t VP8I4ModeOffsets[NUM_BMODES] = {
+ I4DC4, I4TM4, I4VE4, I4HE4, I4RD4, I4VR4, I4LD4, I4VL4, I4HD4, I4HU4
+};
+
+void VP8MakeLuma16Preds(const VP8EncIterator* const it) {
+ const uint8_t* const left = it->x_ ? it->y_left_ : NULL;
+ const uint8_t* const top = it->y_ ? it->y_top_ : NULL;
+ VP8EncPredLuma16(it->yuv_p_, left, top);
+}
+
+void VP8MakeChroma8Preds(const VP8EncIterator* const it) {
+ const uint8_t* const left = it->x_ ? it->u_left_ : NULL;
+ const uint8_t* const top = it->y_ ? it->uv_top_ : NULL;
+ VP8EncPredChroma8(it->yuv_p_, left, top);
+}
+
+void VP8MakeIntra4Preds(const VP8EncIterator* const it) {
+ VP8EncPredLuma4(it->yuv_p_, it->i4_top_);
+}
+
+//------------------------------------------------------------------------------
+// Quantize
+
+// Layout:
+// +----+----+
+// |YYYY|UUVV| 0
+// |YYYY|UUVV| 4
+// |YYYY|....| 8
+// |YYYY|....| 12
+// +----+----+
+
+const uint16_t VP8Scan[16] = { // Luma
+ 0 + 0 * BPS, 4 + 0 * BPS, 8 + 0 * BPS, 12 + 0 * BPS,
+ 0 + 4 * BPS, 4 + 4 * BPS, 8 + 4 * BPS, 12 + 4 * BPS,
+ 0 + 8 * BPS, 4 + 8 * BPS, 8 + 8 * BPS, 12 + 8 * BPS,
+ 0 + 12 * BPS, 4 + 12 * BPS, 8 + 12 * BPS, 12 + 12 * BPS,
+};
+
+static const uint16_t VP8ScanUV[4 + 4] = {
+ 0 + 0 * BPS, 4 + 0 * BPS, 0 + 4 * BPS, 4 + 4 * BPS, // U
+ 8 + 0 * BPS, 12 + 0 * BPS, 8 + 4 * BPS, 12 + 4 * BPS // V
+};
+
+//------------------------------------------------------------------------------
+// Distortion measurement
+
+static const uint16_t kWeightY[16] = {
+ 38, 32, 20, 9, 32, 28, 17, 7, 20, 17, 10, 4, 9, 7, 4, 2
+};
+
+static const uint16_t kWeightTrellis[16] = {
+#if USE_TDISTO == 0
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16
+#else
+ 30, 27, 19, 11,
+ 27, 24, 17, 10,
+ 19, 17, 12, 8,
+ 11, 10, 8, 6
+#endif
+};
+
+// Init/Copy the common fields in score.
+static void InitScore(VP8ModeScore* const rd) {
+ rd->D = 0;
+ rd->SD = 0;
+ rd->R = 0;
+ rd->H = 0;
+ rd->nz = 0;
+ rd->score = MAX_COST;
+}
+
+static void CopyScore(VP8ModeScore* WEBP_RESTRICT const dst,
+ const VP8ModeScore* WEBP_RESTRICT const src) {
+ dst->D = src->D;
+ dst->SD = src->SD;
+ dst->R = src->R;
+ dst->H = src->H;
+ dst->nz = src->nz; // note that nz is not accumulated, but just copied.
+ dst->score = src->score;
+}
+
+static void AddScore(VP8ModeScore* WEBP_RESTRICT const dst,
+ const VP8ModeScore* WEBP_RESTRICT const src) {
+ dst->D += src->D;
+ dst->SD += src->SD;
+ dst->R += src->R;
+ dst->H += src->H;
+ dst->nz |= src->nz; // here, new nz bits are accumulated.
+ dst->score += src->score;
+}
+
+//------------------------------------------------------------------------------
+// Performs trellis-optimized quantization.
+
+// Trellis node
+typedef struct {
+ int8_t prev; // best previous node
+ int8_t sign; // sign of coeff_i
+ int16_t level; // level
+} Node;
+
+// Score state
+typedef struct {
+ score_t score; // partial RD score
+ const uint16_t* costs; // shortcut to cost tables
+} ScoreState;
+
+// If a coefficient was quantized to a value Q (using a neutral bias),
+// we test all alternate possibilities between [Q-MIN_DELTA, Q+MAX_DELTA]
+// We don't test negative values though.
+#define MIN_DELTA 0 // how much lower level to try
+#define MAX_DELTA 1 // how much higher
+#define NUM_NODES (MIN_DELTA + 1 + MAX_DELTA)
+#define NODE(n, l) (nodes[(n)][(l) + MIN_DELTA])
+#define SCORE_STATE(n, l) (score_states[n][(l) + MIN_DELTA])
+
+static WEBP_INLINE void SetRDScore(int lambda, VP8ModeScore* const rd) {
+ rd->score = (rd->R + rd->H) * lambda + RD_DISTO_MULT * (rd->D + rd->SD);
+}
+
+static WEBP_INLINE score_t RDScoreTrellis(int lambda, score_t rate,
+ score_t distortion) {
+ return rate * lambda + RD_DISTO_MULT * distortion;
+}
+
+// Coefficient type.
+enum { TYPE_I16_AC = 0, TYPE_I16_DC = 1, TYPE_CHROMA_A = 2, TYPE_I4_AC = 3 };
+
+static int TrellisQuantizeBlock(const VP8Encoder* WEBP_RESTRICT const enc,
+ int16_t in[16], int16_t out[16],
+ int ctx0, int coeff_type,
+ const VP8Matrix* WEBP_RESTRICT const mtx,
+ int lambda) {
+ const ProbaArray* const probas = enc->proba_.coeffs_[coeff_type];
+ CostArrayPtr const costs =
+ (CostArrayPtr)enc->proba_.remapped_costs_[coeff_type];
+ const int first = (coeff_type == TYPE_I16_AC) ? 1 : 0;
+ Node nodes[16][NUM_NODES];
+ ScoreState score_states[2][NUM_NODES];
+ ScoreState* ss_cur = &SCORE_STATE(0, MIN_DELTA);
+ ScoreState* ss_prev = &SCORE_STATE(1, MIN_DELTA);
+ int best_path[3] = {-1, -1, -1}; // store best-last/best-level/best-previous
+ score_t best_score;
+ int n, m, p, last;
+
+ {
+ score_t cost;
+ const int thresh = mtx->q_[1] * mtx->q_[1] / 4;
+ const int last_proba = probas[VP8EncBands[first]][ctx0][0];
+
+ // compute the position of the last interesting coefficient
+ last = first - 1;
+ for (n = 15; n >= first; --n) {
+ const int j = kZigzag[n];
+ const int err = in[j] * in[j];
+ if (err > thresh) {
+ last = n;
+ break;
+ }
+ }
+ // we don't need to go inspect up to n = 16 coeffs. We can just go up
+ // to last + 1 (inclusive) without losing much.
+ if (last < 15) ++last;
+
+ // compute 'skip' score. This is the max score one can do.
+ cost = VP8BitCost(0, last_proba);
+ best_score = RDScoreTrellis(lambda, cost, 0);
+
+ // initialize source node.
+ for (m = -MIN_DELTA; m <= MAX_DELTA; ++m) {
+ const score_t rate = (ctx0 == 0) ? VP8BitCost(1, last_proba) : 0;
+ ss_cur[m].score = RDScoreTrellis(lambda, rate, 0);
+ ss_cur[m].costs = costs[first][ctx0];
+ }
+ }
+
+ // traverse trellis.
+ for (n = first; n <= last; ++n) {
+ const int j = kZigzag[n];
+ const uint32_t Q = mtx->q_[j];
+ const uint32_t iQ = mtx->iq_[j];
+ const uint32_t B = BIAS(0x00); // neutral bias
+ // note: it's important to take sign of the _original_ coeff,
+ // so we don't have to consider level < 0 afterward.
+ const int sign = (in[j] < 0);
+ const uint32_t coeff0 = (sign ? -in[j] : in[j]) + mtx->sharpen_[j];
+ int level0 = QUANTDIV(coeff0, iQ, B);
+ int thresh_level = QUANTDIV(coeff0, iQ, BIAS(0x80));
+ if (thresh_level > MAX_LEVEL) thresh_level = MAX_LEVEL;
+ if (level0 > MAX_LEVEL) level0 = MAX_LEVEL;
+
+ { // Swap current and previous score states
+ ScoreState* const tmp = ss_cur;
+ ss_cur = ss_prev;
+ ss_prev = tmp;
+ }
+
+ // test all alternate level values around level0.
+ for (m = -MIN_DELTA; m <= MAX_DELTA; ++m) {
+ Node* const cur = &NODE(n, m);
+ const int level = level0 + m;
+ const int ctx = (level > 2) ? 2 : level;
+ const int band = VP8EncBands[n + 1];
+ score_t base_score;
+ score_t best_cur_score;
+ int best_prev;
+ score_t cost, score;
+
+ ss_cur[m].costs = costs[n + 1][ctx];
+ if (level < 0 || level > thresh_level) {
+ ss_cur[m].score = MAX_COST;
+ // Node is dead.
+ continue;
+ }
+
+ {
+ // Compute delta_error = how much coding this level will
+ // subtract to max_error as distortion.
+ // Here, distortion = sum of (|coeff_i| - level_i * Q_i)^2
+ const int new_error = coeff0 - level * Q;
+ const int delta_error =
+ kWeightTrellis[j] * (new_error * new_error - coeff0 * coeff0);
+ base_score = RDScoreTrellis(lambda, 0, delta_error);
+ }
+
+ // Inspect all possible non-dead predecessors. Retain only the best one.
+ // The base_score is added to all scores so it is only added for the final
+ // value after the loop.
+ cost = VP8LevelCost(ss_prev[-MIN_DELTA].costs, level);
+ best_cur_score =
+ ss_prev[-MIN_DELTA].score + RDScoreTrellis(lambda, cost, 0);
+ best_prev = -MIN_DELTA;
+ for (p = -MIN_DELTA + 1; p <= MAX_DELTA; ++p) {
+ // Dead nodes (with ss_prev[p].score >= MAX_COST) are automatically
+ // eliminated since their score can't be better than the current best.
+ cost = VP8LevelCost(ss_prev[p].costs, level);
+ // Examine node assuming it's a non-terminal one.
+ score = ss_prev[p].score + RDScoreTrellis(lambda, cost, 0);
+ if (score < best_cur_score) {
+ best_cur_score = score;
+ best_prev = p;
+ }
+ }
+ best_cur_score += base_score;
+ // Store best finding in current node.
+ cur->sign = sign;
+ cur->level = level;
+ cur->prev = best_prev;
+ ss_cur[m].score = best_cur_score;
+
+ // Now, record best terminal node (and thus best entry in the graph).
+ if (level != 0 && best_cur_score < best_score) {
+ const score_t last_pos_cost =
+ (n < 15) ? VP8BitCost(0, probas[band][ctx][0]) : 0;
+ const score_t last_pos_score = RDScoreTrellis(lambda, last_pos_cost, 0);
+ score = best_cur_score + last_pos_score;
+ if (score < best_score) {
+ best_score = score;
+ best_path[0] = n; // best eob position
+ best_path[1] = m; // best node index
+ best_path[2] = best_prev; // best predecessor
+ }
+ }
+ }
+ }
+
+ // Fresh start
+ // Beware! We must preserve in[0]/out[0] value for TYPE_I16_AC case.
+ if (coeff_type == TYPE_I16_AC) {
+ memset(in + 1, 0, 15 * sizeof(*in));
+ memset(out + 1, 0, 15 * sizeof(*out));
+ } else {
+ memset(in, 0, 16 * sizeof(*in));
+ memset(out, 0, 16 * sizeof(*out));
+ }
+ if (best_path[0] == -1) {
+ return 0; // skip!
+ }
+
+ {
+ // Unwind the best path.
+ // Note: best-prev on terminal node is not necessarily equal to the
+ // best_prev for non-terminal. So we patch best_path[2] in.
+ int nz = 0;
+ int best_node = best_path[1];
+ n = best_path[0];
+ NODE(n, best_node).prev = best_path[2]; // force best-prev for terminal
+
+ for (; n >= first; --n) {
+ const Node* const node = &NODE(n, best_node);
+ const int j = kZigzag[n];
+ out[n] = node->sign ? -node->level : node->level;
+ nz |= node->level;
+ in[j] = out[n] * mtx->q_[j];
+ best_node = node->prev;
+ }
+ return (nz != 0);
+ }
+}
+
+#undef NODE
+
+//------------------------------------------------------------------------------
+// Performs: difference, transform, quantize, back-transform, add
+// all at once. Output is the reconstructed block in *yuv_out, and the
+// quantized levels in *levels.
+
+static int ReconstructIntra16(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd,
+ uint8_t* WEBP_RESTRICT const yuv_out,
+ int mode) {
+ const VP8Encoder* const enc = it->enc_;
+ const uint8_t* const ref = it->yuv_p_ + VP8I16ModeOffsets[mode];
+ const uint8_t* const src = it->yuv_in_ + Y_OFF_ENC;
+ const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
+ int nz = 0;
+ int n;
+ int16_t tmp[16][16], dc_tmp[16];
+
+ for (n = 0; n < 16; n += 2) {
+ VP8FTransform2(src + VP8Scan[n], ref + VP8Scan[n], tmp[n]);
+ }
+ VP8FTransformWHT(tmp[0], dc_tmp);
+ nz |= VP8EncQuantizeBlockWHT(dc_tmp, rd->y_dc_levels, &dqm->y2_) << 24;
+
+ if (DO_TRELLIS_I16 && it->do_trellis_) {
+ int x, y;
+ VP8IteratorNzToBytes(it);
+ for (y = 0, n = 0; y < 4; ++y) {
+ for (x = 0; x < 4; ++x, ++n) {
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ const int non_zero = TrellisQuantizeBlock(
+ enc, tmp[n], rd->y_ac_levels[n], ctx, TYPE_I16_AC, &dqm->y1_,
+ dqm->lambda_trellis_i16_);
+ it->top_nz_[x] = it->left_nz_[y] = non_zero;
+ rd->y_ac_levels[n][0] = 0;
+ nz |= non_zero << n;
+ }
+ }
+ } else {
+ for (n = 0; n < 16; n += 2) {
+ // Zero-out the first coeff, so that: a) nz is correct below, and
+ // b) finding 'last' non-zero coeffs in SetResidualCoeffs() is simplified.
+ tmp[n][0] = tmp[n + 1][0] = 0;
+ nz |= VP8EncQuantize2Blocks(tmp[n], rd->y_ac_levels[n], &dqm->y1_) << n;
+ assert(rd->y_ac_levels[n + 0][0] == 0);
+ assert(rd->y_ac_levels[n + 1][0] == 0);
+ }
+ }
+
+ // Transform back
+ VP8TransformWHT(dc_tmp, tmp[0]);
+ for (n = 0; n < 16; n += 2) {
+ VP8ITransform(ref + VP8Scan[n], tmp[n], yuv_out + VP8Scan[n], 1);
+ }
+
+ return nz;
+}
+
+static int ReconstructIntra4(VP8EncIterator* WEBP_RESTRICT const it,
+ int16_t levels[16],
+ const uint8_t* WEBP_RESTRICT const src,
+ uint8_t* WEBP_RESTRICT const yuv_out,
+ int mode) {
+ const VP8Encoder* const enc = it->enc_;
+ const uint8_t* const ref = it->yuv_p_ + VP8I4ModeOffsets[mode];
+ const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
+ int nz = 0;
+ int16_t tmp[16];
+
+ VP8FTransform(src, ref, tmp);
+ if (DO_TRELLIS_I4 && it->do_trellis_) {
+ const int x = it->i4_ & 3, y = it->i4_ >> 2;
+ const int ctx = it->top_nz_[x] + it->left_nz_[y];
+ nz = TrellisQuantizeBlock(enc, tmp, levels, ctx, TYPE_I4_AC, &dqm->y1_,
+ dqm->lambda_trellis_i4_);
+ } else {
+ nz = VP8EncQuantizeBlock(tmp, levels, &dqm->y1_);
+ }
+ VP8ITransform(ref, tmp, yuv_out, 0);
+ return nz;
+}
+
+//------------------------------------------------------------------------------
+// DC-error diffusion
+
+// Diffusion weights. We under-correct a bit (15/16th of the error is actually
+// diffused) to avoid 'rainbow' chessboard pattern of blocks at q~=0.
+#define C1 7 // fraction of error sent to the 4x4 block below
+#define C2 8 // fraction of error sent to the 4x4 block on the right
+#define DSHIFT 4
+#define DSCALE 1 // storage descaling, needed to make the error fit int8_t
+
+// Quantize as usual, but also compute and return the quantization error.
+// Error is already divided by DSHIFT.
+static int QuantizeSingle(int16_t* WEBP_RESTRICT const v,
+ const VP8Matrix* WEBP_RESTRICT const mtx) {
+ int V = *v;
+ const int sign = (V < 0);
+ if (sign) V = -V;
+ if (V > (int)mtx->zthresh_[0]) {
+ const int qV = QUANTDIV(V, mtx->iq_[0], mtx->bias_[0]) * mtx->q_[0];
+ const int err = (V - qV);
+ *v = sign ? -qV : qV;
+ return (sign ? -err : err) >> DSCALE;
+ }
+ *v = 0;
+ return (sign ? -V : V) >> DSCALE;
+}
+
+static void CorrectDCValues(const VP8EncIterator* WEBP_RESTRICT const it,
+ const VP8Matrix* WEBP_RESTRICT const mtx,
+ int16_t tmp[][16],
+ VP8ModeScore* WEBP_RESTRICT const rd) {
+ // | top[0] | top[1]
+ // --------+--------+---------
+ // left[0] | tmp[0] tmp[1] <-> err0 err1
+ // left[1] | tmp[2] tmp[3] err2 err3
+ //
+ // Final errors {err1,err2,err3} are preserved and later restored
+ // as top[]/left[] on the next block.
+ int ch;
+ for (ch = 0; ch <= 1; ++ch) {
+ const int8_t* const top = it->top_derr_[it->x_][ch];
+ const int8_t* const left = it->left_derr_[ch];
+ int16_t (* const c)[16] = &tmp[ch * 4];
+ int err0, err1, err2, err3;
+ c[0][0] += (C1 * top[0] + C2 * left[0]) >> (DSHIFT - DSCALE);
+ err0 = QuantizeSingle(&c[0][0], mtx);
+ c[1][0] += (C1 * top[1] + C2 * err0) >> (DSHIFT - DSCALE);
+ err1 = QuantizeSingle(&c[1][0], mtx);
+ c[2][0] += (C1 * err0 + C2 * left[1]) >> (DSHIFT - DSCALE);
+ err2 = QuantizeSingle(&c[2][0], mtx);
+ c[3][0] += (C1 * err1 + C2 * err2) >> (DSHIFT - DSCALE);
+ err3 = QuantizeSingle(&c[3][0], mtx);
+ // error 'err' is bounded by mtx->q_[0] which is 132 at max. Hence
+ // err >> DSCALE will fit in an int8_t type if DSCALE>=1.
+ assert(abs(err1) <= 127 && abs(err2) <= 127 && abs(err3) <= 127);
+ rd->derr[ch][0] = (int8_t)err1;
+ rd->derr[ch][1] = (int8_t)err2;
+ rd->derr[ch][2] = (int8_t)err3;
+ }
+}
+
+static void StoreDiffusionErrors(VP8EncIterator* WEBP_RESTRICT const it,
+ const VP8ModeScore* WEBP_RESTRICT const rd) {
+ int ch;
+ for (ch = 0; ch <= 1; ++ch) {
+ int8_t* const top = it->top_derr_[it->x_][ch];
+ int8_t* const left = it->left_derr_[ch];
+ left[0] = rd->derr[ch][0]; // restore err1
+ left[1] = 3 * rd->derr[ch][2] >> 2; // ... 3/4th of err3
+ top[0] = rd->derr[ch][1]; // ... err2
+ top[1] = rd->derr[ch][2] - left[1]; // ... 1/4th of err3.
+ }
+}
+
+#undef C1
+#undef C2
+#undef DSHIFT
+#undef DSCALE
+
+//------------------------------------------------------------------------------
+
+static int ReconstructUV(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd,
+ uint8_t* WEBP_RESTRICT const yuv_out, int mode) {
+ const VP8Encoder* const enc = it->enc_;
+ const uint8_t* const ref = it->yuv_p_ + VP8UVModeOffsets[mode];
+ const uint8_t* const src = it->yuv_in_ + U_OFF_ENC;
+ const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
+ int nz = 0;
+ int n;
+ int16_t tmp[8][16];
+
+ for (n = 0; n < 8; n += 2) {
+ VP8FTransform2(src + VP8ScanUV[n], ref + VP8ScanUV[n], tmp[n]);
+ }
+ if (it->top_derr_ != NULL) CorrectDCValues(it, &dqm->uv_, tmp, rd);
+
+ if (DO_TRELLIS_UV && it->do_trellis_) {
+ int ch, x, y;
+ for (ch = 0, n = 0; ch <= 2; ch += 2) {
+ for (y = 0; y < 2; ++y) {
+ for (x = 0; x < 2; ++x, ++n) {
+ const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
+ const int non_zero = TrellisQuantizeBlock(
+ enc, tmp[n], rd->uv_levels[n], ctx, TYPE_CHROMA_A, &dqm->uv_,
+ dqm->lambda_trellis_uv_);
+ it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] = non_zero;
+ nz |= non_zero << n;
+ }
+ }
+ }
+ } else {
+ for (n = 0; n < 8; n += 2) {
+ nz |= VP8EncQuantize2Blocks(tmp[n], rd->uv_levels[n], &dqm->uv_) << n;
+ }
+ }
+
+ for (n = 0; n < 8; n += 2) {
+ VP8ITransform(ref + VP8ScanUV[n], tmp[n], yuv_out + VP8ScanUV[n], 1);
+ }
+ return (nz << 16);
+}
+
+//------------------------------------------------------------------------------
+// RD-opt decision. Reconstruct each modes, evalue distortion and bit-cost.
+// Pick the mode is lower RD-cost = Rate + lambda * Distortion.
+
+static void StoreMaxDelta(VP8SegmentInfo* const dqm, const int16_t DCs[16]) {
+ // We look at the first three AC coefficients to determine what is the average
+ // delta between each sub-4x4 block.
+ const int v0 = abs(DCs[1]);
+ const int v1 = abs(DCs[2]);
+ const int v2 = abs(DCs[4]);
+ int max_v = (v1 > v0) ? v1 : v0;
+ max_v = (v2 > max_v) ? v2 : max_v;
+ if (max_v > dqm->max_edge_) dqm->max_edge_ = max_v;
+}
+
+static void SwapModeScore(VP8ModeScore** a, VP8ModeScore** b) {
+ VP8ModeScore* const tmp = *a;
+ *a = *b;
+ *b = tmp;
+}
+
+static void SwapPtr(uint8_t** a, uint8_t** b) {
+ uint8_t* const tmp = *a;
+ *a = *b;
+ *b = tmp;
+}
+
+static void SwapOut(VP8EncIterator* const it) {
+ SwapPtr(&it->yuv_out_, &it->yuv_out2_);
+}
+
+static void PickBestIntra16(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT rd) {
+ const int kNumBlocks = 16;
+ VP8SegmentInfo* const dqm = &it->enc_->dqm_[it->mb_->segment_];
+ const int lambda = dqm->lambda_i16_;
+ const int tlambda = dqm->tlambda_;
+ const uint8_t* const src = it->yuv_in_ + Y_OFF_ENC;
+ VP8ModeScore rd_tmp;
+ VP8ModeScore* rd_cur = &rd_tmp;
+ VP8ModeScore* rd_best = rd;
+ int mode;
+ int is_flat = IsFlatSource16(it->yuv_in_ + Y_OFF_ENC);
+
+ rd->mode_i16 = -1;
+ for (mode = 0; mode < NUM_PRED_MODES; ++mode) {
+ uint8_t* const tmp_dst = it->yuv_out2_ + Y_OFF_ENC; // scratch buffer
+ rd_cur->mode_i16 = mode;
+
+ // Reconstruct
+ rd_cur->nz = ReconstructIntra16(it, rd_cur, tmp_dst, mode);
+
+ // Measure RD-score
+ rd_cur->D = VP8SSE16x16(src, tmp_dst);
+ rd_cur->SD =
+ tlambda ? MULT_8B(tlambda, VP8TDisto16x16(src, tmp_dst, kWeightY)) : 0;
+ rd_cur->H = VP8FixedCostsI16[mode];
+ rd_cur->R = VP8GetCostLuma16(it, rd_cur);
+ if (is_flat) {
+ // refine the first impression (which was in pixel space)
+ is_flat = IsFlat(rd_cur->y_ac_levels[0], kNumBlocks, FLATNESS_LIMIT_I16);
+ if (is_flat) {
+ // Block is very flat. We put emphasis on the distortion being very low!
+ rd_cur->D *= 2;
+ rd_cur->SD *= 2;
+ }
+ }
+
+ // Since we always examine Intra16 first, we can overwrite *rd directly.
+ SetRDScore(lambda, rd_cur);
+ if (mode == 0 || rd_cur->score < rd_best->score) {
+ SwapModeScore(&rd_cur, &rd_best);
+ SwapOut(it);
+ }
+ }
+ if (rd_best != rd) {
+ memcpy(rd, rd_best, sizeof(*rd));
+ }
+ SetRDScore(dqm->lambda_mode_, rd); // finalize score for mode decision.
+ VP8SetIntra16Mode(it, rd->mode_i16);
+
+ // we have a blocky macroblock (only DCs are non-zero) with fairly high
+ // distortion, record max delta so we can later adjust the minimal filtering
+ // strength needed to smooth these blocks out.
+ if ((rd->nz & 0x100ffff) == 0x1000000 && rd->D > dqm->min_disto_) {
+ StoreMaxDelta(dqm, rd->y_dc_levels);
+ }
+}
+
+//------------------------------------------------------------------------------
+
+// return the cost array corresponding to the surrounding prediction modes.
+static const uint16_t* GetCostModeI4(VP8EncIterator* WEBP_RESTRICT const it,
+ const uint8_t modes[16]) {
+ const int preds_w = it->enc_->preds_w_;
+ const int x = (it->i4_ & 3), y = it->i4_ >> 2;
+ const int left = (x == 0) ? it->preds_[y * preds_w - 1] : modes[it->i4_ - 1];
+ const int top = (y == 0) ? it->preds_[-preds_w + x] : modes[it->i4_ - 4];
+ return VP8FixedCostsI4[top][left];
+}
+
+static int PickBestIntra4(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd) {
+ const VP8Encoder* const enc = it->enc_;
+ const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
+ const int lambda = dqm->lambda_i4_;
+ const int tlambda = dqm->tlambda_;
+ const uint8_t* const src0 = it->yuv_in_ + Y_OFF_ENC;
+ uint8_t* const best_blocks = it->yuv_out2_ + Y_OFF_ENC;
+ int total_header_bits = 0;
+ VP8ModeScore rd_best;
+
+ if (enc->max_i4_header_bits_ == 0) {
+ return 0;
+ }
+
+ InitScore(&rd_best);
+ rd_best.H = 211; // '211' is the value of VP8BitCost(0, 145)
+ SetRDScore(dqm->lambda_mode_, &rd_best);
+ VP8IteratorStartI4(it);
+ do {
+ const int kNumBlocks = 1;
+ VP8ModeScore rd_i4;
+ int mode;
+ int best_mode = -1;
+ const uint8_t* const src = src0 + VP8Scan[it->i4_];
+ const uint16_t* const mode_costs = GetCostModeI4(it, rd->modes_i4);
+ uint8_t* best_block = best_blocks + VP8Scan[it->i4_];
+ uint8_t* tmp_dst = it->yuv_p_ + I4TMP; // scratch buffer.
+
+ InitScore(&rd_i4);
+ VP8MakeIntra4Preds(it);
+ for (mode = 0; mode < NUM_BMODES; ++mode) {
+ VP8ModeScore rd_tmp;
+ int16_t tmp_levels[16];
+
+ // Reconstruct
+ rd_tmp.nz =
+ ReconstructIntra4(it, tmp_levels, src, tmp_dst, mode) << it->i4_;
+
+ // Compute RD-score
+ rd_tmp.D = VP8SSE4x4(src, tmp_dst);
+ rd_tmp.SD =
+ tlambda ? MULT_8B(tlambda, VP8TDisto4x4(src, tmp_dst, kWeightY))
+ : 0;
+ rd_tmp.H = mode_costs[mode];
+
+ // Add flatness penalty, to avoid flat area to be mispredicted
+ // by a complex mode.
+ if (mode > 0 && IsFlat(tmp_levels, kNumBlocks, FLATNESS_LIMIT_I4)) {
+ rd_tmp.R = FLATNESS_PENALTY * kNumBlocks;
+ } else {
+ rd_tmp.R = 0;
+ }
+
+ // early-out check
+ SetRDScore(lambda, &rd_tmp);
+ if (best_mode >= 0 && rd_tmp.score >= rd_i4.score) continue;
+
+ // finish computing score
+ rd_tmp.R += VP8GetCostLuma4(it, tmp_levels);
+ SetRDScore(lambda, &rd_tmp);
+
+ if (best_mode < 0 || rd_tmp.score < rd_i4.score) {
+ CopyScore(&rd_i4, &rd_tmp);
+ best_mode = mode;
+ SwapPtr(&tmp_dst, &best_block);
+ memcpy(rd_best.y_ac_levels[it->i4_], tmp_levels,
+ sizeof(rd_best.y_ac_levels[it->i4_]));
+ }
+ }
+ SetRDScore(dqm->lambda_mode_, &rd_i4);
+ AddScore(&rd_best, &rd_i4);
+ if (rd_best.score >= rd->score) {
+ return 0;
+ }
+ total_header_bits += (int)rd_i4.H; // <- equal to mode_costs[best_mode];
+ if (total_header_bits > enc->max_i4_header_bits_) {
+ return 0;
+ }
+ // Copy selected samples if not in the right place already.
+ if (best_block != best_blocks + VP8Scan[it->i4_]) {
+ VP8Copy4x4(best_block, best_blocks + VP8Scan[it->i4_]);
+ }
+ rd->modes_i4[it->i4_] = best_mode;
+ it->top_nz_[it->i4_ & 3] = it->left_nz_[it->i4_ >> 2] = (rd_i4.nz ? 1 : 0);
+ } while (VP8IteratorRotateI4(it, best_blocks));
+
+ // finalize state
+ CopyScore(rd, &rd_best);
+ VP8SetIntra4Mode(it, rd->modes_i4);
+ SwapOut(it);
+ memcpy(rd->y_ac_levels, rd_best.y_ac_levels, sizeof(rd->y_ac_levels));
+ return 1; // select intra4x4 over intra16x16
+}
+
+//------------------------------------------------------------------------------
+
+static void PickBestUV(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd) {
+ const int kNumBlocks = 8;
+ const VP8SegmentInfo* const dqm = &it->enc_->dqm_[it->mb_->segment_];
+ const int lambda = dqm->lambda_uv_;
+ const uint8_t* const src = it->yuv_in_ + U_OFF_ENC;
+ uint8_t* tmp_dst = it->yuv_out2_ + U_OFF_ENC; // scratch buffer
+ uint8_t* dst0 = it->yuv_out_ + U_OFF_ENC;
+ uint8_t* dst = dst0;
+ VP8ModeScore rd_best;
+ int mode;
+
+ rd->mode_uv = -1;
+ InitScore(&rd_best);
+ for (mode = 0; mode < NUM_PRED_MODES; ++mode) {
+ VP8ModeScore rd_uv;
+
+ // Reconstruct
+ rd_uv.nz = ReconstructUV(it, &rd_uv, tmp_dst, mode);
+
+ // Compute RD-score
+ rd_uv.D = VP8SSE16x8(src, tmp_dst);
+ rd_uv.SD = 0; // not calling TDisto here: it tends to flatten areas.
+ rd_uv.H = VP8FixedCostsUV[mode];
+ rd_uv.R = VP8GetCostUV(it, &rd_uv);
+ if (mode > 0 && IsFlat(rd_uv.uv_levels[0], kNumBlocks, FLATNESS_LIMIT_UV)) {
+ rd_uv.R += FLATNESS_PENALTY * kNumBlocks;
+ }
+
+ SetRDScore(lambda, &rd_uv);
+ if (mode == 0 || rd_uv.score < rd_best.score) {
+ CopyScore(&rd_best, &rd_uv);
+ rd->mode_uv = mode;
+ memcpy(rd->uv_levels, rd_uv.uv_levels, sizeof(rd->uv_levels));
+ if (it->top_derr_ != NULL) {
+ memcpy(rd->derr, rd_uv.derr, sizeof(rd_uv.derr));
+ }
+ SwapPtr(&dst, &tmp_dst);
+ }
+ }
+ VP8SetIntraUVMode(it, rd->mode_uv);
+ AddScore(rd, &rd_best);
+ if (dst != dst0) { // copy 16x8 block if needed
+ VP8Copy16x8(dst, dst0);
+ }
+ if (it->top_derr_ != NULL) { // store diffusion errors for next block
+ StoreDiffusionErrors(it, rd);
+ }
+}
+
+//------------------------------------------------------------------------------
+// Final reconstruction and quantization.
+
+static void SimpleQuantize(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd) {
+ const VP8Encoder* const enc = it->enc_;
+ const int is_i16 = (it->mb_->type_ == 1);
+ int nz = 0;
+
+ if (is_i16) {
+ nz = ReconstructIntra16(it, rd, it->yuv_out_ + Y_OFF_ENC, it->preds_[0]);
+ } else {
+ VP8IteratorStartI4(it);
+ do {
+ const int mode =
+ it->preds_[(it->i4_ & 3) + (it->i4_ >> 2) * enc->preds_w_];
+ const uint8_t* const src = it->yuv_in_ + Y_OFF_ENC + VP8Scan[it->i4_];
+ uint8_t* const dst = it->yuv_out_ + Y_OFF_ENC + VP8Scan[it->i4_];
+ VP8MakeIntra4Preds(it);
+ nz |= ReconstructIntra4(it, rd->y_ac_levels[it->i4_],
+ src, dst, mode) << it->i4_;
+ } while (VP8IteratorRotateI4(it, it->yuv_out_ + Y_OFF_ENC));
+ }
+
+ nz |= ReconstructUV(it, rd, it->yuv_out_ + U_OFF_ENC, it->mb_->uv_mode_);
+ rd->nz = nz;
+}
+
+// Refine intra16/intra4 sub-modes based on distortion only (not rate).
+static void RefineUsingDistortion(VP8EncIterator* WEBP_RESTRICT const it,
+ int try_both_modes, int refine_uv_mode,
+ VP8ModeScore* WEBP_RESTRICT const rd) {
+ score_t best_score = MAX_COST;
+ int nz = 0;
+ int mode;
+ int is_i16 = try_both_modes || (it->mb_->type_ == 1);
+
+ const VP8SegmentInfo* const dqm = &it->enc_->dqm_[it->mb_->segment_];
+ // Some empiric constants, of approximate order of magnitude.
+ const int lambda_d_i16 = 106;
+ const int lambda_d_i4 = 11;
+ const int lambda_d_uv = 120;
+ score_t score_i4 = dqm->i4_penalty_;
+ score_t i4_bit_sum = 0;
+ const score_t bit_limit = try_both_modes ? it->enc_->mb_header_limit_
+ : MAX_COST; // no early-out allowed
+
+ if (is_i16) { // First, evaluate Intra16 distortion
+ int best_mode = -1;
+ const uint8_t* const src = it->yuv_in_ + Y_OFF_ENC;
+ for (mode = 0; mode < NUM_PRED_MODES; ++mode) {
+ const uint8_t* const ref = it->yuv_p_ + VP8I16ModeOffsets[mode];
+ const score_t score = (score_t)VP8SSE16x16(src, ref) * RD_DISTO_MULT
+ + VP8FixedCostsI16[mode] * lambda_d_i16;
+ if (mode > 0 && VP8FixedCostsI16[mode] > bit_limit) {
+ continue;
+ }
+
+ if (score < best_score) {
+ best_mode = mode;
+ best_score = score;
+ }
+ }
+ if (it->x_ == 0 || it->y_ == 0) {
+ // avoid starting a checkerboard resonance from the border. See bug #432.
+ if (IsFlatSource16(src)) {
+ best_mode = (it->x_ == 0) ? 0 : 2;
+ try_both_modes = 0; // stick to i16
+ }
+ }
+ VP8SetIntra16Mode(it, best_mode);
+ // we'll reconstruct later, if i16 mode actually gets selected
+ }
+
+ // Next, evaluate Intra4
+ if (try_both_modes || !is_i16) {
+ // We don't evaluate the rate here, but just account for it through a
+ // constant penalty (i4 mode usually needs more bits compared to i16).
+ is_i16 = 0;
+ VP8IteratorStartI4(it);
+ do {
+ int best_i4_mode = -1;
+ score_t best_i4_score = MAX_COST;
+ const uint8_t* const src = it->yuv_in_ + Y_OFF_ENC + VP8Scan[it->i4_];
+ const uint16_t* const mode_costs = GetCostModeI4(it, rd->modes_i4);
+
+ VP8MakeIntra4Preds(it);
+ for (mode = 0; mode < NUM_BMODES; ++mode) {
+ const uint8_t* const ref = it->yuv_p_ + VP8I4ModeOffsets[mode];
+ const score_t score = VP8SSE4x4(src, ref) * RD_DISTO_MULT
+ + mode_costs[mode] * lambda_d_i4;
+ if (score < best_i4_score) {
+ best_i4_mode = mode;
+ best_i4_score = score;
+ }
+ }
+ i4_bit_sum += mode_costs[best_i4_mode];
+ rd->modes_i4[it->i4_] = best_i4_mode;
+ score_i4 += best_i4_score;
+ if (score_i4 >= best_score || i4_bit_sum > bit_limit) {
+ // Intra4 won't be better than Intra16. Bail out and pick Intra16.
+ is_i16 = 1;
+ break;
+ } else { // reconstruct partial block inside yuv_out2_ buffer
+ uint8_t* const tmp_dst = it->yuv_out2_ + Y_OFF_ENC + VP8Scan[it->i4_];
+ nz |= ReconstructIntra4(it, rd->y_ac_levels[it->i4_],
+ src, tmp_dst, best_i4_mode) << it->i4_;
+ }
+ } while (VP8IteratorRotateI4(it, it->yuv_out2_ + Y_OFF_ENC));
+ }
+
+ // Final reconstruction, depending on which mode is selected.
+ if (!is_i16) {
+ VP8SetIntra4Mode(it, rd->modes_i4);
+ SwapOut(it);
+ best_score = score_i4;
+ } else {
+ nz = ReconstructIntra16(it, rd, it->yuv_out_ + Y_OFF_ENC, it->preds_[0]);
+ }
+
+ // ... and UV!
+ if (refine_uv_mode) {
+ int best_mode = -1;
+ score_t best_uv_score = MAX_COST;
+ const uint8_t* const src = it->yuv_in_ + U_OFF_ENC;
+ for (mode = 0; mode < NUM_PRED_MODES; ++mode) {
+ const uint8_t* const ref = it->yuv_p_ + VP8UVModeOffsets[mode];
+ const score_t score = VP8SSE16x8(src, ref) * RD_DISTO_MULT
+ + VP8FixedCostsUV[mode] * lambda_d_uv;
+ if (score < best_uv_score) {
+ best_mode = mode;
+ best_uv_score = score;
+ }
+ }
+ VP8SetIntraUVMode(it, best_mode);
+ }
+ nz |= ReconstructUV(it, rd, it->yuv_out_ + U_OFF_ENC, it->mb_->uv_mode_);
+
+ rd->nz = nz;
+ rd->score = best_score;
+}
+
+//------------------------------------------------------------------------------
+// Entry point
+
+int VP8Decimate(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd,
+ VP8RDLevel rd_opt) {
+ int is_skipped;
+ const int method = it->enc_->method_;
+
+ InitScore(rd);
+
+ // We can perform predictions for Luma16x16 and Chroma8x8 already.
+ // Luma4x4 predictions needs to be done as-we-go.
+ VP8MakeLuma16Preds(it);
+ VP8MakeChroma8Preds(it);
+
+ if (rd_opt > RD_OPT_NONE) {
+ it->do_trellis_ = (rd_opt >= RD_OPT_TRELLIS_ALL);
+ PickBestIntra16(it, rd);
+ if (method >= 2) {
+ PickBestIntra4(it, rd);
+ }
+ PickBestUV(it, rd);
+ if (rd_opt == RD_OPT_TRELLIS) { // finish off with trellis-optim now
+ it->do_trellis_ = 1;
+ SimpleQuantize(it, rd);
+ }
+ } else {
+ // At this point we have heuristically decided intra16 / intra4.
+ // For method >= 2, pick the best intra4/intra16 based on SSE (~tad slower).
+ // For method <= 1, we don't re-examine the decision but just go ahead with
+ // quantization/reconstruction.
+ RefineUsingDistortion(it, (method >= 2), (method >= 1), rd);
+ }
+ is_skipped = (rd->nz == 0);
+ VP8SetSkip(it, is_skipped);
+ return is_skipped;
+}
diff --git a/media/libwebp/src/enc/syntax_enc.c b/media/libwebp/src/enc/syntax_enc.c
new file mode 100644
index 0000000000..e18cf650ca
--- /dev/null
+++ b/media/libwebp/src/enc/syntax_enc.c
@@ -0,0 +1,388 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Header syntax writing
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+
+#include "src/utils/utils.h"
+#include "src/webp/format_constants.h" // RIFF constants
+#include "src/webp/mux_types.h" // ALPHA_FLAG
+#include "src/enc/vp8i_enc.h"
+
+//------------------------------------------------------------------------------
+// Helper functions
+
+static int IsVP8XNeeded(const VP8Encoder* const enc) {
+ return !!enc->has_alpha_; // Currently the only case when VP8X is needed.
+ // This could change in the future.
+}
+
+static int PutPaddingByte(const WebPPicture* const pic) {
+ const uint8_t pad_byte[1] = { 0 };
+ return !!pic->writer(pad_byte, 1, pic);
+}
+
+//------------------------------------------------------------------------------
+// Writers for header's various pieces (in order of appearance)
+
+static WebPEncodingError PutRIFFHeader(const VP8Encoder* const enc,
+ size_t riff_size) {
+ const WebPPicture* const pic = enc->pic_;
+ uint8_t riff[RIFF_HEADER_SIZE] = {
+ 'R', 'I', 'F', 'F', 0, 0, 0, 0, 'W', 'E', 'B', 'P'
+ };
+ assert(riff_size == (uint32_t)riff_size);
+ PutLE32(riff + TAG_SIZE, (uint32_t)riff_size);
+ if (!pic->writer(riff, sizeof(riff), pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+ return VP8_ENC_OK;
+}
+
+static WebPEncodingError PutVP8XHeader(const VP8Encoder* const enc) {
+ const WebPPicture* const pic = enc->pic_;
+ uint8_t vp8x[CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE] = {
+ 'V', 'P', '8', 'X'
+ };
+ uint32_t flags = 0;
+
+ assert(IsVP8XNeeded(enc));
+ assert(pic->width >= 1 && pic->height >= 1);
+ assert(pic->width <= MAX_CANVAS_SIZE && pic->height <= MAX_CANVAS_SIZE);
+
+ if (enc->has_alpha_) {
+ flags |= ALPHA_FLAG;
+ }
+
+ PutLE32(vp8x + TAG_SIZE, VP8X_CHUNK_SIZE);
+ PutLE32(vp8x + CHUNK_HEADER_SIZE, flags);
+ PutLE24(vp8x + CHUNK_HEADER_SIZE + 4, pic->width - 1);
+ PutLE24(vp8x + CHUNK_HEADER_SIZE + 7, pic->height - 1);
+ if (!pic->writer(vp8x, sizeof(vp8x), pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+ return VP8_ENC_OK;
+}
+
+static WebPEncodingError PutAlphaChunk(const VP8Encoder* const enc) {
+ const WebPPicture* const pic = enc->pic_;
+ uint8_t alpha_chunk_hdr[CHUNK_HEADER_SIZE] = {
+ 'A', 'L', 'P', 'H'
+ };
+
+ assert(enc->has_alpha_);
+
+ // Alpha chunk header.
+ PutLE32(alpha_chunk_hdr + TAG_SIZE, enc->alpha_data_size_);
+ if (!pic->writer(alpha_chunk_hdr, sizeof(alpha_chunk_hdr), pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+
+ // Alpha chunk data.
+ if (!pic->writer(enc->alpha_data_, enc->alpha_data_size_, pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+
+ // Padding.
+ if ((enc->alpha_data_size_ & 1) && !PutPaddingByte(pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+ return VP8_ENC_OK;
+}
+
+static WebPEncodingError PutVP8Header(const WebPPicture* const pic,
+ size_t vp8_size) {
+ uint8_t vp8_chunk_hdr[CHUNK_HEADER_SIZE] = {
+ 'V', 'P', '8', ' '
+ };
+ assert(vp8_size == (uint32_t)vp8_size);
+ PutLE32(vp8_chunk_hdr + TAG_SIZE, (uint32_t)vp8_size);
+ if (!pic->writer(vp8_chunk_hdr, sizeof(vp8_chunk_hdr), pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+ return VP8_ENC_OK;
+}
+
+static WebPEncodingError PutVP8FrameHeader(const WebPPicture* const pic,
+ int profile, size_t size0) {
+ uint8_t vp8_frm_hdr[VP8_FRAME_HEADER_SIZE];
+ uint32_t bits;
+
+ if (size0 >= VP8_MAX_PARTITION0_SIZE) { // partition #0 is too big to fit
+ return VP8_ENC_ERROR_PARTITION0_OVERFLOW;
+ }
+
+ // Paragraph 9.1.
+ bits = 0 // keyframe (1b)
+ | (profile << 1) // profile (3b)
+ | (1 << 4) // visible (1b)
+ | ((uint32_t)size0 << 5); // partition length (19b)
+ vp8_frm_hdr[0] = (bits >> 0) & 0xff;
+ vp8_frm_hdr[1] = (bits >> 8) & 0xff;
+ vp8_frm_hdr[2] = (bits >> 16) & 0xff;
+ // signature
+ vp8_frm_hdr[3] = (VP8_SIGNATURE >> 16) & 0xff;
+ vp8_frm_hdr[4] = (VP8_SIGNATURE >> 8) & 0xff;
+ vp8_frm_hdr[5] = (VP8_SIGNATURE >> 0) & 0xff;
+ // dimensions
+ vp8_frm_hdr[6] = pic->width & 0xff;
+ vp8_frm_hdr[7] = pic->width >> 8;
+ vp8_frm_hdr[8] = pic->height & 0xff;
+ vp8_frm_hdr[9] = pic->height >> 8;
+
+ if (!pic->writer(vp8_frm_hdr, sizeof(vp8_frm_hdr), pic)) {
+ return VP8_ENC_ERROR_BAD_WRITE;
+ }
+ return VP8_ENC_OK;
+}
+
+// WebP Headers.
+static int PutWebPHeaders(const VP8Encoder* const enc, size_t size0,
+ size_t vp8_size, size_t riff_size) {
+ WebPPicture* const pic = enc->pic_;
+ WebPEncodingError err = VP8_ENC_OK;
+
+ // RIFF header.
+ err = PutRIFFHeader(enc, riff_size);
+ if (err != VP8_ENC_OK) goto Error;
+
+ // VP8X.
+ if (IsVP8XNeeded(enc)) {
+ err = PutVP8XHeader(enc);
+ if (err != VP8_ENC_OK) goto Error;
+ }
+
+ // Alpha.
+ if (enc->has_alpha_) {
+ err = PutAlphaChunk(enc);
+ if (err != VP8_ENC_OK) goto Error;
+ }
+
+ // VP8 header.
+ err = PutVP8Header(pic, vp8_size);
+ if (err != VP8_ENC_OK) goto Error;
+
+ // VP8 frame header.
+ err = PutVP8FrameHeader(pic, enc->profile_, size0);
+ if (err != VP8_ENC_OK) goto Error;
+
+ // All OK.
+ return 1;
+
+ // Error.
+ Error:
+ return WebPEncodingSetError(pic, err);
+}
+
+// Segmentation header
+static void PutSegmentHeader(VP8BitWriter* const bw,
+ const VP8Encoder* const enc) {
+ const VP8EncSegmentHeader* const hdr = &enc->segment_hdr_;
+ const VP8EncProba* const proba = &enc->proba_;
+ if (VP8PutBitUniform(bw, (hdr->num_segments_ > 1))) {
+ // We always 'update' the quant and filter strength values
+ const int update_data = 1;
+ int s;
+ VP8PutBitUniform(bw, hdr->update_map_);
+ if (VP8PutBitUniform(bw, update_data)) {
+ // we always use absolute values, not relative ones
+ VP8PutBitUniform(bw, 1); // (segment_feature_mode = 1. Paragraph 9.3.)
+ for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
+ VP8PutSignedBits(bw, enc->dqm_[s].quant_, 7);
+ }
+ for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
+ VP8PutSignedBits(bw, enc->dqm_[s].fstrength_, 6);
+ }
+ }
+ if (hdr->update_map_) {
+ for (s = 0; s < 3; ++s) {
+ if (VP8PutBitUniform(bw, (proba->segments_[s] != 255u))) {
+ VP8PutBits(bw, proba->segments_[s], 8);
+ }
+ }
+ }
+ }
+}
+
+// Filtering parameters header
+static void PutFilterHeader(VP8BitWriter* const bw,
+ const VP8EncFilterHeader* const hdr) {
+ const int use_lf_delta = (hdr->i4x4_lf_delta_ != 0);
+ VP8PutBitUniform(bw, hdr->simple_);
+ VP8PutBits(bw, hdr->level_, 6);
+ VP8PutBits(bw, hdr->sharpness_, 3);
+ if (VP8PutBitUniform(bw, use_lf_delta)) {
+ // '0' is the default value for i4x4_lf_delta_ at frame #0.
+ const int need_update = (hdr->i4x4_lf_delta_ != 0);
+ if (VP8PutBitUniform(bw, need_update)) {
+ // we don't use ref_lf_delta => emit four 0 bits
+ VP8PutBits(bw, 0, 4);
+ // we use mode_lf_delta for i4x4
+ VP8PutSignedBits(bw, hdr->i4x4_lf_delta_, 6);
+ VP8PutBits(bw, 0, 3); // all others unused
+ }
+ }
+}
+
+// Nominal quantization parameters
+static void PutQuant(VP8BitWriter* const bw,
+ const VP8Encoder* const enc) {
+ VP8PutBits(bw, enc->base_quant_, 7);
+ VP8PutSignedBits(bw, enc->dq_y1_dc_, 4);
+ VP8PutSignedBits(bw, enc->dq_y2_dc_, 4);
+ VP8PutSignedBits(bw, enc->dq_y2_ac_, 4);
+ VP8PutSignedBits(bw, enc->dq_uv_dc_, 4);
+ VP8PutSignedBits(bw, enc->dq_uv_ac_, 4);
+}
+
+// Partition sizes
+static int EmitPartitionsSize(const VP8Encoder* const enc,
+ WebPPicture* const pic) {
+ uint8_t buf[3 * (MAX_NUM_PARTITIONS - 1)];
+ int p;
+ for (p = 0; p < enc->num_parts_ - 1; ++p) {
+ const size_t part_size = VP8BitWriterSize(enc->parts_ + p);
+ if (part_size >= VP8_MAX_PARTITION_SIZE) {
+ return WebPEncodingSetError(pic, VP8_ENC_ERROR_PARTITION_OVERFLOW);
+ }
+ buf[3 * p + 0] = (part_size >> 0) & 0xff;
+ buf[3 * p + 1] = (part_size >> 8) & 0xff;
+ buf[3 * p + 2] = (part_size >> 16) & 0xff;
+ }
+ return p ? pic->writer(buf, 3 * p, pic) : 1;
+}
+
+//------------------------------------------------------------------------------
+
+static int GeneratePartition0(VP8Encoder* const enc) {
+ VP8BitWriter* const bw = &enc->bw_;
+ const int mb_size = enc->mb_w_ * enc->mb_h_;
+ uint64_t pos1, pos2, pos3;
+
+ pos1 = VP8BitWriterPos(bw);
+ if (!VP8BitWriterInit(bw, mb_size * 7 / 8)) { // ~7 bits per macroblock
+ return WebPEncodingSetError(enc->pic_, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ VP8PutBitUniform(bw, 0); // colorspace
+ VP8PutBitUniform(bw, 0); // clamp type
+
+ PutSegmentHeader(bw, enc);
+ PutFilterHeader(bw, &enc->filter_hdr_);
+ VP8PutBits(bw, enc->num_parts_ == 8 ? 3 :
+ enc->num_parts_ == 4 ? 2 :
+ enc->num_parts_ == 2 ? 1 : 0, 2);
+ PutQuant(bw, enc);
+ VP8PutBitUniform(bw, 0); // no proba update
+ VP8WriteProbas(bw, &enc->proba_);
+ pos2 = VP8BitWriterPos(bw);
+ VP8CodeIntraModes(enc);
+ VP8BitWriterFinish(bw);
+
+ pos3 = VP8BitWriterPos(bw);
+
+#if !defined(WEBP_DISABLE_STATS)
+ if (enc->pic_->stats) {
+ enc->pic_->stats->header_bytes[0] = (int)((pos2 - pos1 + 7) >> 3);
+ enc->pic_->stats->header_bytes[1] = (int)((pos3 - pos2 + 7) >> 3);
+ enc->pic_->stats->alpha_data_size = (int)enc->alpha_data_size_;
+ }
+#else
+ (void)pos1;
+ (void)pos2;
+ (void)pos3;
+#endif
+ if (bw->error_) {
+ return WebPEncodingSetError(enc->pic_, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ return 1;
+}
+
+void VP8EncFreeBitWriters(VP8Encoder* const enc) {
+ int p;
+ VP8BitWriterWipeOut(&enc->bw_);
+ for (p = 0; p < enc->num_parts_; ++p) {
+ VP8BitWriterWipeOut(enc->parts_ + p);
+ }
+}
+
+int VP8EncWrite(VP8Encoder* const enc) {
+ WebPPicture* const pic = enc->pic_;
+ VP8BitWriter* const bw = &enc->bw_;
+ const int task_percent = 19;
+ const int percent_per_part = task_percent / enc->num_parts_;
+ const int final_percent = enc->percent_ + task_percent;
+ int ok = 0;
+ size_t vp8_size, pad, riff_size;
+ int p;
+
+ // Partition #0 with header and partition sizes
+ ok = GeneratePartition0(enc);
+ if (!ok) return 0;
+
+ // Compute VP8 size
+ vp8_size = VP8_FRAME_HEADER_SIZE +
+ VP8BitWriterSize(bw) +
+ 3 * (enc->num_parts_ - 1);
+ for (p = 0; p < enc->num_parts_; ++p) {
+ vp8_size += VP8BitWriterSize(enc->parts_ + p);
+ }
+ pad = vp8_size & 1;
+ vp8_size += pad;
+
+ // Compute RIFF size
+ // At the minimum it is: "WEBPVP8 nnnn" + VP8 data size.
+ riff_size = TAG_SIZE + CHUNK_HEADER_SIZE + vp8_size;
+ if (IsVP8XNeeded(enc)) { // Add size for: VP8X header + data.
+ riff_size += CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE;
+ }
+ if (enc->has_alpha_) { // Add size for: ALPH header + data.
+ const uint32_t padded_alpha_size = enc->alpha_data_size_ +
+ (enc->alpha_data_size_ & 1);
+ riff_size += CHUNK_HEADER_SIZE + padded_alpha_size;
+ }
+ // RIFF size should fit in 32-bits.
+ if (riff_size > 0xfffffffeU) {
+ return WebPEncodingSetError(pic, VP8_ENC_ERROR_FILE_TOO_BIG);
+ }
+
+ // Emit headers and partition #0
+ {
+ const uint8_t* const part0 = VP8BitWriterBuf(bw);
+ const size_t size0 = VP8BitWriterSize(bw);
+ ok = ok && PutWebPHeaders(enc, size0, vp8_size, riff_size)
+ && pic->writer(part0, size0, pic)
+ && EmitPartitionsSize(enc, pic);
+ VP8BitWriterWipeOut(bw); // will free the internal buffer.
+ }
+
+ // Token partitions
+ for (p = 0; p < enc->num_parts_; ++p) {
+ const uint8_t* const buf = VP8BitWriterBuf(enc->parts_ + p);
+ const size_t size = VP8BitWriterSize(enc->parts_ + p);
+ if (size) ok = ok && pic->writer(buf, size, pic);
+ VP8BitWriterWipeOut(enc->parts_ + p); // will free the internal buffer.
+ ok = ok && WebPReportProgress(pic, enc->percent_ + percent_per_part,
+ &enc->percent_);
+ }
+
+ // Padding byte
+ if (ok && pad) {
+ ok = PutPaddingByte(pic);
+ }
+
+ enc->coded_size_ = (int)(CHUNK_HEADER_SIZE + riff_size);
+ ok = ok && WebPReportProgress(pic, final_percent, &enc->percent_);
+ return ok;
+}
+
+//------------------------------------------------------------------------------
+
diff --git a/media/libwebp/src/enc/token_enc.c b/media/libwebp/src/enc/token_enc.c
new file mode 100644
index 0000000000..3a2192acac
--- /dev/null
+++ b/media/libwebp/src/enc/token_enc.c
@@ -0,0 +1,262 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Paginated token buffer
+//
+// A 'token' is a bit value associated with a probability, either fixed
+// or a later-to-be-determined after statistics have been collected.
+// For dynamic probability, we just record the slot id (idx) for the probability
+// value in the final probability array (uint8_t* probas in VP8EmitTokens).
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "src/enc/cost_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/utils/utils.h"
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+// we use pages to reduce the number of memcpy()
+#define MIN_PAGE_SIZE 8192 // minimum number of token per page
+#define FIXED_PROBA_BIT (1u << 14)
+
+typedef uint16_t token_t; // bit #15: bit value
+ // bit #14: flags for constant proba or idx
+ // bits #0..13: slot or constant proba
+struct VP8Tokens {
+ VP8Tokens* next_; // pointer to next page
+};
+// Token data is located in memory just after the next_ field.
+// This macro is used to return their address and hide the trick.
+#define TOKEN_DATA(p) ((const token_t*)&(p)[1])
+
+//------------------------------------------------------------------------------
+
+void VP8TBufferInit(VP8TBuffer* const b, int page_size) {
+ b->tokens_ = NULL;
+ b->pages_ = NULL;
+ b->last_page_ = &b->pages_;
+ b->left_ = 0;
+ b->page_size_ = (page_size < MIN_PAGE_SIZE) ? MIN_PAGE_SIZE : page_size;
+ b->error_ = 0;
+}
+
+void VP8TBufferClear(VP8TBuffer* const b) {
+ if (b != NULL) {
+ VP8Tokens* p = b->pages_;
+ while (p != NULL) {
+ VP8Tokens* const next = p->next_;
+ WebPSafeFree(p);
+ p = next;
+ }
+ VP8TBufferInit(b, b->page_size_);
+ }
+}
+
+static int TBufferNewPage(VP8TBuffer* const b) {
+ VP8Tokens* page = NULL;
+ if (!b->error_) {
+ const size_t size = sizeof(*page) + b->page_size_ * sizeof(token_t);
+ page = (VP8Tokens*)WebPSafeMalloc(1ULL, size);
+ }
+ if (page == NULL) {
+ b->error_ = 1;
+ return 0;
+ }
+ page->next_ = NULL;
+
+ *b->last_page_ = page;
+ b->last_page_ = &page->next_;
+ b->left_ = b->page_size_;
+ b->tokens_ = (token_t*)TOKEN_DATA(page);
+ return 1;
+}
+
+//------------------------------------------------------------------------------
+
+#define TOKEN_ID(t, b, ctx) \
+ (NUM_PROBAS * ((ctx) + NUM_CTX * ((b) + NUM_BANDS * (t))))
+
+static WEBP_INLINE uint32_t AddToken(VP8TBuffer* const b, uint32_t bit,
+ uint32_t proba_idx,
+ proba_t* const stats) {
+ assert(proba_idx < FIXED_PROBA_BIT);
+ assert(bit <= 1);
+ if (b->left_ > 0 || TBufferNewPage(b)) {
+ const int slot = --b->left_;
+ b->tokens_[slot] = (bit << 15) | proba_idx;
+ }
+ VP8RecordStats(bit, stats);
+ return bit;
+}
+
+static WEBP_INLINE void AddConstantToken(VP8TBuffer* const b,
+ uint32_t bit, uint32_t proba) {
+ assert(proba < 256);
+ assert(bit <= 1);
+ if (b->left_ > 0 || TBufferNewPage(b)) {
+ const int slot = --b->left_;
+ b->tokens_[slot] = (bit << 15) | FIXED_PROBA_BIT | proba;
+ }
+}
+
+int VP8RecordCoeffTokens(int ctx, const struct VP8Residual* const res,
+ VP8TBuffer* const tokens) {
+ const int16_t* const coeffs = res->coeffs;
+ const int coeff_type = res->coeff_type;
+ const int last = res->last;
+ int n = res->first;
+ uint32_t base_id = TOKEN_ID(coeff_type, n, ctx);
+ // should be stats[VP8EncBands[n]], but it's equivalent for n=0 or 1
+ proba_t* s = res->stats[n][ctx];
+ if (!AddToken(tokens, last >= 0, base_id + 0, s + 0)) {
+ return 0;
+ }
+
+ while (n < 16) {
+ const int c = coeffs[n++];
+ const int sign = c < 0;
+ const uint32_t v = sign ? -c : c;
+ if (!AddToken(tokens, v != 0, base_id + 1, s + 1)) {
+ base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 0); // ctx=0
+ s = res->stats[VP8EncBands[n]][0];
+ continue;
+ }
+ if (!AddToken(tokens, v > 1, base_id + 2, s + 2)) {
+ base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 1); // ctx=1
+ s = res->stats[VP8EncBands[n]][1];
+ } else {
+ if (!AddToken(tokens, v > 4, base_id + 3, s + 3)) {
+ if (AddToken(tokens, v != 2, base_id + 4, s + 4)) {
+ AddToken(tokens, v == 4, base_id + 5, s + 5);
+ }
+ } else if (!AddToken(tokens, v > 10, base_id + 6, s + 6)) {
+ if (!AddToken(tokens, v > 6, base_id + 7, s + 7)) {
+ AddConstantToken(tokens, v == 6, 159);
+ } else {
+ AddConstantToken(tokens, v >= 9, 165);
+ AddConstantToken(tokens, !(v & 1), 145);
+ }
+ } else {
+ int mask;
+ const uint8_t* tab;
+ uint32_t residue = v - 3;
+ if (residue < (8 << 1)) { // VP8Cat3 (3b)
+ AddToken(tokens, 0, base_id + 8, s + 8);
+ AddToken(tokens, 0, base_id + 9, s + 9);
+ residue -= (8 << 0);
+ mask = 1 << 2;
+ tab = VP8Cat3;
+ } else if (residue < (8 << 2)) { // VP8Cat4 (4b)
+ AddToken(tokens, 0, base_id + 8, s + 8);
+ AddToken(tokens, 1, base_id + 9, s + 9);
+ residue -= (8 << 1);
+ mask = 1 << 3;
+ tab = VP8Cat4;
+ } else if (residue < (8 << 3)) { // VP8Cat5 (5b)
+ AddToken(tokens, 1, base_id + 8, s + 8);
+ AddToken(tokens, 0, base_id + 10, s + 9);
+ residue -= (8 << 2);
+ mask = 1 << 4;
+ tab = VP8Cat5;
+ } else { // VP8Cat6 (11b)
+ AddToken(tokens, 1, base_id + 8, s + 8);
+ AddToken(tokens, 1, base_id + 10, s + 9);
+ residue -= (8 << 3);
+ mask = 1 << 10;
+ tab = VP8Cat6;
+ }
+ while (mask) {
+ AddConstantToken(tokens, !!(residue & mask), *tab++);
+ mask >>= 1;
+ }
+ }
+ base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 2); // ctx=2
+ s = res->stats[VP8EncBands[n]][2];
+ }
+ AddConstantToken(tokens, sign, 128);
+ if (n == 16 || !AddToken(tokens, n <= last, base_id + 0, s + 0)) {
+ return 1; // EOB
+ }
+ }
+ return 1;
+}
+
+#undef TOKEN_ID
+
+//------------------------------------------------------------------------------
+// Final coding pass, with known probabilities
+
+int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
+ const uint8_t* const probas, int final_pass) {
+ const VP8Tokens* p = b->pages_;
+ assert(!b->error_);
+ while (p != NULL) {
+ const VP8Tokens* const next = p->next_;
+ const int N = (next == NULL) ? b->left_ : 0;
+ int n = b->page_size_;
+ const token_t* const tokens = TOKEN_DATA(p);
+ while (n-- > N) {
+ const token_t token = tokens[n];
+ const int bit = (token >> 15) & 1;
+ if (token & FIXED_PROBA_BIT) {
+ VP8PutBit(bw, bit, token & 0xffu); // constant proba
+ } else {
+ VP8PutBit(bw, bit, probas[token & 0x3fffu]);
+ }
+ }
+ if (final_pass) WebPSafeFree((void*)p);
+ p = next;
+ }
+ if (final_pass) b->pages_ = NULL;
+ return 1;
+}
+
+// Size estimation
+size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas) {
+ size_t size = 0;
+ const VP8Tokens* p = b->pages_;
+ assert(!b->error_);
+ while (p != NULL) {
+ const VP8Tokens* const next = p->next_;
+ const int N = (next == NULL) ? b->left_ : 0;
+ int n = b->page_size_;
+ const token_t* const tokens = TOKEN_DATA(p);
+ while (n-- > N) {
+ const token_t token = tokens[n];
+ const int bit = token & (1 << 15);
+ if (token & FIXED_PROBA_BIT) {
+ size += VP8BitCost(bit, token & 0xffu);
+ } else {
+ size += VP8BitCost(bit, probas[token & 0x3fffu]);
+ }
+ }
+ p = next;
+ }
+ return size;
+}
+
+//------------------------------------------------------------------------------
+
+#else // DISABLE_TOKEN_BUFFER
+
+void VP8TBufferInit(VP8TBuffer* const b, int page_size) {
+ (void)b;
+ (void)page_size;
+}
+void VP8TBufferClear(VP8TBuffer* const b) {
+ (void)b;
+}
+
+#endif // !DISABLE_TOKEN_BUFFER
+
diff --git a/media/libwebp/src/enc/tree_enc.c b/media/libwebp/src/enc/tree_enc.c
new file mode 100644
index 0000000000..64ed28360b
--- /dev/null
+++ b/media/libwebp/src/enc/tree_enc.c
@@ -0,0 +1,504 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Coding of token probabilities, intra modes and segments.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "src/enc/vp8i_enc.h"
+
+//------------------------------------------------------------------------------
+// Default probabilities
+
+// Paragraph 13.5
+const uint8_t
+ VP8CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS] = {
+ { { { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 }
+ },
+ { { 253, 136, 254, 255, 228, 219, 128, 128, 128, 128, 128 },
+ { 189, 129, 242, 255, 227, 213, 255, 219, 128, 128, 128 },
+ { 106, 126, 227, 252, 214, 209, 255, 255, 128, 128, 128 }
+ },
+ { { 1, 98, 248, 255, 236, 226, 255, 255, 128, 128, 128 },
+ { 181, 133, 238, 254, 221, 234, 255, 154, 128, 128, 128 },
+ { 78, 134, 202, 247, 198, 180, 255, 219, 128, 128, 128 },
+ },
+ { { 1, 185, 249, 255, 243, 255, 128, 128, 128, 128, 128 },
+ { 184, 150, 247, 255, 236, 224, 128, 128, 128, 128, 128 },
+ { 77, 110, 216, 255, 236, 230, 128, 128, 128, 128, 128 },
+ },
+ { { 1, 101, 251, 255, 241, 255, 128, 128, 128, 128, 128 },
+ { 170, 139, 241, 252, 236, 209, 255, 255, 128, 128, 128 },
+ { 37, 116, 196, 243, 228, 255, 255, 255, 128, 128, 128 }
+ },
+ { { 1, 204, 254, 255, 245, 255, 128, 128, 128, 128, 128 },
+ { 207, 160, 250, 255, 238, 128, 128, 128, 128, 128, 128 },
+ { 102, 103, 231, 255, 211, 171, 128, 128, 128, 128, 128 }
+ },
+ { { 1, 152, 252, 255, 240, 255, 128, 128, 128, 128, 128 },
+ { 177, 135, 243, 255, 234, 225, 128, 128, 128, 128, 128 },
+ { 80, 129, 211, 255, 194, 224, 128, 128, 128, 128, 128 }
+ },
+ { { 1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 246, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 255, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 }
+ }
+ },
+ { { { 198, 35, 237, 223, 193, 187, 162, 160, 145, 155, 62 },
+ { 131, 45, 198, 221, 172, 176, 220, 157, 252, 221, 1 },
+ { 68, 47, 146, 208, 149, 167, 221, 162, 255, 223, 128 }
+ },
+ { { 1, 149, 241, 255, 221, 224, 255, 255, 128, 128, 128 },
+ { 184, 141, 234, 253, 222, 220, 255, 199, 128, 128, 128 },
+ { 81, 99, 181, 242, 176, 190, 249, 202, 255, 255, 128 }
+ },
+ { { 1, 129, 232, 253, 214, 197, 242, 196, 255, 255, 128 },
+ { 99, 121, 210, 250, 201, 198, 255, 202, 128, 128, 128 },
+ { 23, 91, 163, 242, 170, 187, 247, 210, 255, 255, 128 }
+ },
+ { { 1, 200, 246, 255, 234, 255, 128, 128, 128, 128, 128 },
+ { 109, 178, 241, 255, 231, 245, 255, 255, 128, 128, 128 },
+ { 44, 130, 201, 253, 205, 192, 255, 255, 128, 128, 128 }
+ },
+ { { 1, 132, 239, 251, 219, 209, 255, 165, 128, 128, 128 },
+ { 94, 136, 225, 251, 218, 190, 255, 255, 128, 128, 128 },
+ { 22, 100, 174, 245, 186, 161, 255, 199, 128, 128, 128 }
+ },
+ { { 1, 182, 249, 255, 232, 235, 128, 128, 128, 128, 128 },
+ { 124, 143, 241, 255, 227, 234, 128, 128, 128, 128, 128 },
+ { 35, 77, 181, 251, 193, 211, 255, 205, 128, 128, 128 }
+ },
+ { { 1, 157, 247, 255, 236, 231, 255, 255, 128, 128, 128 },
+ { 121, 141, 235, 255, 225, 227, 255, 255, 128, 128, 128 },
+ { 45, 99, 188, 251, 195, 217, 255, 224, 128, 128, 128 }
+ },
+ { { 1, 1, 251, 255, 213, 255, 128, 128, 128, 128, 128 },
+ { 203, 1, 248, 255, 255, 128, 128, 128, 128, 128, 128 },
+ { 137, 1, 177, 255, 224, 255, 128, 128, 128, 128, 128 }
+ }
+ },
+ { { { 253, 9, 248, 251, 207, 208, 255, 192, 128, 128, 128 },
+ { 175, 13, 224, 243, 193, 185, 249, 198, 255, 255, 128 },
+ { 73, 17, 171, 221, 161, 179, 236, 167, 255, 234, 128 }
+ },
+ { { 1, 95, 247, 253, 212, 183, 255, 255, 128, 128, 128 },
+ { 239, 90, 244, 250, 211, 209, 255, 255, 128, 128, 128 },
+ { 155, 77, 195, 248, 188, 195, 255, 255, 128, 128, 128 }
+ },
+ { { 1, 24, 239, 251, 218, 219, 255, 205, 128, 128, 128 },
+ { 201, 51, 219, 255, 196, 186, 128, 128, 128, 128, 128 },
+ { 69, 46, 190, 239, 201, 218, 255, 228, 128, 128, 128 }
+ },
+ { { 1, 191, 251, 255, 255, 128, 128, 128, 128, 128, 128 },
+ { 223, 165, 249, 255, 213, 255, 128, 128, 128, 128, 128 },
+ { 141, 124, 248, 255, 255, 128, 128, 128, 128, 128, 128 }
+ },
+ { { 1, 16, 248, 255, 255, 128, 128, 128, 128, 128, 128 },
+ { 190, 36, 230, 255, 236, 255, 128, 128, 128, 128, 128 },
+ { 149, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 }
+ },
+ { { 1, 226, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 247, 192, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 240, 128, 255, 128, 128, 128, 128, 128, 128, 128, 128 }
+ },
+ { { 1, 134, 252, 255, 255, 128, 128, 128, 128, 128, 128 },
+ { 213, 62, 250, 255, 255, 128, 128, 128, 128, 128, 128 },
+ { 55, 93, 255, 128, 128, 128, 128, 128, 128, 128, 128 }
+ },
+ { { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128 }
+ }
+ },
+ { { { 202, 24, 213, 235, 186, 191, 220, 160, 240, 175, 255 },
+ { 126, 38, 182, 232, 169, 184, 228, 174, 255, 187, 128 },
+ { 61, 46, 138, 219, 151, 178, 240, 170, 255, 216, 128 }
+ },
+ { { 1, 112, 230, 250, 199, 191, 247, 159, 255, 255, 128 },
+ { 166, 109, 228, 252, 211, 215, 255, 174, 128, 128, 128 },
+ { 39, 77, 162, 232, 172, 180, 245, 178, 255, 255, 128 }
+ },
+ { { 1, 52, 220, 246, 198, 199, 249, 220, 255, 255, 128 },
+ { 124, 74, 191, 243, 183, 193, 250, 221, 255, 255, 128 },
+ { 24, 71, 130, 219, 154, 170, 243, 182, 255, 255, 128 }
+ },
+ { { 1, 182, 225, 249, 219, 240, 255, 224, 128, 128, 128 },
+ { 149, 150, 226, 252, 216, 205, 255, 171, 128, 128, 128 },
+ { 28, 108, 170, 242, 183, 194, 254, 223, 255, 255, 128 }
+ },
+ { { 1, 81, 230, 252, 204, 203, 255, 192, 128, 128, 128 },
+ { 123, 102, 209, 247, 188, 196, 255, 233, 128, 128, 128 },
+ { 20, 95, 153, 243, 164, 173, 255, 203, 128, 128, 128 }
+ },
+ { { 1, 222, 248, 255, 216, 213, 128, 128, 128, 128, 128 },
+ { 168, 175, 246, 252, 235, 205, 255, 255, 128, 128, 128 },
+ { 47, 116, 215, 255, 211, 212, 255, 255, 128, 128, 128 }
+ },
+ { { 1, 121, 236, 253, 212, 214, 255, 255, 128, 128, 128 },
+ { 141, 84, 213, 252, 201, 202, 255, 219, 128, 128, 128 },
+ { 42, 80, 160, 240, 162, 185, 255, 205, 128, 128, 128 }
+ },
+ { { 1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 244, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 },
+ { 238, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128 }
+ }
+ }
+};
+
+void VP8DefaultProbas(VP8Encoder* const enc) {
+ VP8EncProba* const probas = &enc->proba_;
+ probas->use_skip_proba_ = 0;
+ memset(probas->segments_, 255u, sizeof(probas->segments_));
+ memcpy(probas->coeffs_, VP8CoeffsProba0, sizeof(VP8CoeffsProba0));
+ // Note: we could hard-code the level_costs_ corresponding to VP8CoeffsProba0,
+ // but that's ~11k of static data. Better call VP8CalculateLevelCosts() later.
+ probas->dirty_ = 1;
+}
+
+// Paragraph 11.5. 900bytes.
+static const uint8_t kBModesProba[NUM_BMODES][NUM_BMODES][NUM_BMODES - 1] = {
+ { { 231, 120, 48, 89, 115, 113, 120, 152, 112 },
+ { 152, 179, 64, 126, 170, 118, 46, 70, 95 },
+ { 175, 69, 143, 80, 85, 82, 72, 155, 103 },
+ { 56, 58, 10, 171, 218, 189, 17, 13, 152 },
+ { 114, 26, 17, 163, 44, 195, 21, 10, 173 },
+ { 121, 24, 80, 195, 26, 62, 44, 64, 85 },
+ { 144, 71, 10, 38, 171, 213, 144, 34, 26 },
+ { 170, 46, 55, 19, 136, 160, 33, 206, 71 },
+ { 63, 20, 8, 114, 114, 208, 12, 9, 226 },
+ { 81, 40, 11, 96, 182, 84, 29, 16, 36 } },
+ { { 134, 183, 89, 137, 98, 101, 106, 165, 148 },
+ { 72, 187, 100, 130, 157, 111, 32, 75, 80 },
+ { 66, 102, 167, 99, 74, 62, 40, 234, 128 },
+ { 41, 53, 9, 178, 241, 141, 26, 8, 107 },
+ { 74, 43, 26, 146, 73, 166, 49, 23, 157 },
+ { 65, 38, 105, 160, 51, 52, 31, 115, 128 },
+ { 104, 79, 12, 27, 217, 255, 87, 17, 7 },
+ { 87, 68, 71, 44, 114, 51, 15, 186, 23 },
+ { 47, 41, 14, 110, 182, 183, 21, 17, 194 },
+ { 66, 45, 25, 102, 197, 189, 23, 18, 22 } },
+ { { 88, 88, 147, 150, 42, 46, 45, 196, 205 },
+ { 43, 97, 183, 117, 85, 38, 35, 179, 61 },
+ { 39, 53, 200, 87, 26, 21, 43, 232, 171 },
+ { 56, 34, 51, 104, 114, 102, 29, 93, 77 },
+ { 39, 28, 85, 171, 58, 165, 90, 98, 64 },
+ { 34, 22, 116, 206, 23, 34, 43, 166, 73 },
+ { 107, 54, 32, 26, 51, 1, 81, 43, 31 },
+ { 68, 25, 106, 22, 64, 171, 36, 225, 114 },
+ { 34, 19, 21, 102, 132, 188, 16, 76, 124 },
+ { 62, 18, 78, 95, 85, 57, 50, 48, 51 } },
+ { { 193, 101, 35, 159, 215, 111, 89, 46, 111 },
+ { 60, 148, 31, 172, 219, 228, 21, 18, 111 },
+ { 112, 113, 77, 85, 179, 255, 38, 120, 114 },
+ { 40, 42, 1, 196, 245, 209, 10, 25, 109 },
+ { 88, 43, 29, 140, 166, 213, 37, 43, 154 },
+ { 61, 63, 30, 155, 67, 45, 68, 1, 209 },
+ { 100, 80, 8, 43, 154, 1, 51, 26, 71 },
+ { 142, 78, 78, 16, 255, 128, 34, 197, 171 },
+ { 41, 40, 5, 102, 211, 183, 4, 1, 221 },
+ { 51, 50, 17, 168, 209, 192, 23, 25, 82 } },
+ { { 138, 31, 36, 171, 27, 166, 38, 44, 229 },
+ { 67, 87, 58, 169, 82, 115, 26, 59, 179 },
+ { 63, 59, 90, 180, 59, 166, 93, 73, 154 },
+ { 40, 40, 21, 116, 143, 209, 34, 39, 175 },
+ { 47, 15, 16, 183, 34, 223, 49, 45, 183 },
+ { 46, 17, 33, 183, 6, 98, 15, 32, 183 },
+ { 57, 46, 22, 24, 128, 1, 54, 17, 37 },
+ { 65, 32, 73, 115, 28, 128, 23, 128, 205 },
+ { 40, 3, 9, 115, 51, 192, 18, 6, 223 },
+ { 87, 37, 9, 115, 59, 77, 64, 21, 47 } },
+ { { 104, 55, 44, 218, 9, 54, 53, 130, 226 },
+ { 64, 90, 70, 205, 40, 41, 23, 26, 57 },
+ { 54, 57, 112, 184, 5, 41, 38, 166, 213 },
+ { 30, 34, 26, 133, 152, 116, 10, 32, 134 },
+ { 39, 19, 53, 221, 26, 114, 32, 73, 255 },
+ { 31, 9, 65, 234, 2, 15, 1, 118, 73 },
+ { 75, 32, 12, 51, 192, 255, 160, 43, 51 },
+ { 88, 31, 35, 67, 102, 85, 55, 186, 85 },
+ { 56, 21, 23, 111, 59, 205, 45, 37, 192 },
+ { 55, 38, 70, 124, 73, 102, 1, 34, 98 } },
+ { { 125, 98, 42, 88, 104, 85, 117, 175, 82 },
+ { 95, 84, 53, 89, 128, 100, 113, 101, 45 },
+ { 75, 79, 123, 47, 51, 128, 81, 171, 1 },
+ { 57, 17, 5, 71, 102, 57, 53, 41, 49 },
+ { 38, 33, 13, 121, 57, 73, 26, 1, 85 },
+ { 41, 10, 67, 138, 77, 110, 90, 47, 114 },
+ { 115, 21, 2, 10, 102, 255, 166, 23, 6 },
+ { 101, 29, 16, 10, 85, 128, 101, 196, 26 },
+ { 57, 18, 10, 102, 102, 213, 34, 20, 43 },
+ { 117, 20, 15, 36, 163, 128, 68, 1, 26 } },
+ { { 102, 61, 71, 37, 34, 53, 31, 243, 192 },
+ { 69, 60, 71, 38, 73, 119, 28, 222, 37 },
+ { 68, 45, 128, 34, 1, 47, 11, 245, 171 },
+ { 62, 17, 19, 70, 146, 85, 55, 62, 70 },
+ { 37, 43, 37, 154, 100, 163, 85, 160, 1 },
+ { 63, 9, 92, 136, 28, 64, 32, 201, 85 },
+ { 75, 15, 9, 9, 64, 255, 184, 119, 16 },
+ { 86, 6, 28, 5, 64, 255, 25, 248, 1 },
+ { 56, 8, 17, 132, 137, 255, 55, 116, 128 },
+ { 58, 15, 20, 82, 135, 57, 26, 121, 40 } },
+ { { 164, 50, 31, 137, 154, 133, 25, 35, 218 },
+ { 51, 103, 44, 131, 131, 123, 31, 6, 158 },
+ { 86, 40, 64, 135, 148, 224, 45, 183, 128 },
+ { 22, 26, 17, 131, 240, 154, 14, 1, 209 },
+ { 45, 16, 21, 91, 64, 222, 7, 1, 197 },
+ { 56, 21, 39, 155, 60, 138, 23, 102, 213 },
+ { 83, 12, 13, 54, 192, 255, 68, 47, 28 },
+ { 85, 26, 85, 85, 128, 128, 32, 146, 171 },
+ { 18, 11, 7, 63, 144, 171, 4, 4, 246 },
+ { 35, 27, 10, 146, 174, 171, 12, 26, 128 } },
+ { { 190, 80, 35, 99, 180, 80, 126, 54, 45 },
+ { 85, 126, 47, 87, 176, 51, 41, 20, 32 },
+ { 101, 75, 128, 139, 118, 146, 116, 128, 85 },
+ { 56, 41, 15, 176, 236, 85, 37, 9, 62 },
+ { 71, 30, 17, 119, 118, 255, 17, 18, 138 },
+ { 101, 38, 60, 138, 55, 70, 43, 26, 142 },
+ { 146, 36, 19, 30, 171, 255, 97, 27, 20 },
+ { 138, 45, 61, 62, 219, 1, 81, 188, 64 },
+ { 32, 41, 20, 117, 151, 142, 20, 21, 163 },
+ { 112, 19, 12, 61, 195, 128, 48, 4, 24 } }
+};
+
+static int PutI4Mode(VP8BitWriter* const bw, int mode,
+ const uint8_t* const prob) {
+ if (VP8PutBit(bw, mode != B_DC_PRED, prob[0])) {
+ if (VP8PutBit(bw, mode != B_TM_PRED, prob[1])) {
+ if (VP8PutBit(bw, mode != B_VE_PRED, prob[2])) {
+ if (!VP8PutBit(bw, mode >= B_LD_PRED, prob[3])) {
+ if (VP8PutBit(bw, mode != B_HE_PRED, prob[4])) {
+ VP8PutBit(bw, mode != B_RD_PRED, prob[5]);
+ }
+ } else {
+ if (VP8PutBit(bw, mode != B_LD_PRED, prob[6])) {
+ if (VP8PutBit(bw, mode != B_VL_PRED, prob[7])) {
+ VP8PutBit(bw, mode != B_HD_PRED, prob[8]);
+ }
+ }
+ }
+ }
+ }
+ }
+ return mode;
+}
+
+static void PutI16Mode(VP8BitWriter* const bw, int mode) {
+ if (VP8PutBit(bw, (mode == TM_PRED || mode == H_PRED), 156)) {
+ VP8PutBit(bw, mode == TM_PRED, 128); // TM or HE
+ } else {
+ VP8PutBit(bw, mode == V_PRED, 163); // VE or DC
+ }
+}
+
+static void PutUVMode(VP8BitWriter* const bw, int uv_mode) {
+ if (VP8PutBit(bw, uv_mode != DC_PRED, 142)) {
+ if (VP8PutBit(bw, uv_mode != V_PRED, 114)) {
+ VP8PutBit(bw, uv_mode != H_PRED, 183); // else: TM_PRED
+ }
+ }
+}
+
+static void PutSegment(VP8BitWriter* const bw, int s, const uint8_t* p) {
+ if (VP8PutBit(bw, s >= 2, p[0])) p += 1;
+ VP8PutBit(bw, s & 1, p[1]);
+}
+
+void VP8CodeIntraModes(VP8Encoder* const enc) {
+ VP8BitWriter* const bw = &enc->bw_;
+ VP8EncIterator it;
+ VP8IteratorInit(enc, &it);
+ do {
+ const VP8MBInfo* const mb = it.mb_;
+ const uint8_t* preds = it.preds_;
+ if (enc->segment_hdr_.update_map_) {
+ PutSegment(bw, mb->segment_, enc->proba_.segments_);
+ }
+ if (enc->proba_.use_skip_proba_) {
+ VP8PutBit(bw, mb->skip_, enc->proba_.skip_proba_);
+ }
+ if (VP8PutBit(bw, (mb->type_ != 0), 145)) { // i16x16
+ PutI16Mode(bw, preds[0]);
+ } else {
+ const int preds_w = enc->preds_w_;
+ const uint8_t* top_pred = preds - preds_w;
+ int x, y;
+ for (y = 0; y < 4; ++y) {
+ int left = preds[-1];
+ for (x = 0; x < 4; ++x) {
+ const uint8_t* const probas = kBModesProba[top_pred[x]][left];
+ left = PutI4Mode(bw, preds[x], probas);
+ }
+ top_pred = preds;
+ preds += preds_w;
+ }
+ }
+ PutUVMode(bw, mb->uv_mode_);
+ } while (VP8IteratorNext(&it));
+}
+
+//------------------------------------------------------------------------------
+// Paragraph 13
+
+const uint8_t
+ VP8CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS] = {
+ { { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 176, 246, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 223, 241, 252, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 249, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 244, 252, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 234, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 246, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 239, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 251, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 251, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 253, 255, 254, 255, 255, 255, 255, 255, 255 },
+ { 250, 255, 254, 255, 254, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ }
+ },
+ { { { 217, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 225, 252, 241, 253, 255, 255, 254, 255, 255, 255, 255 },
+ { 234, 250, 241, 250, 253, 255, 253, 254, 255, 255, 255 }
+ },
+ { { 255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 223, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 238, 253, 254, 254, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 249, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 253, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 247, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 252, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ }
+ },
+ { { { 186, 251, 250, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 234, 251, 244, 254, 255, 255, 255, 255, 255, 255, 255 },
+ { 251, 251, 243, 253, 254, 255, 254, 255, 255, 255, 255 }
+ },
+ { { 255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 236, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 251, 253, 253, 254, 254, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ }
+ },
+ { { { 248, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 250, 254, 252, 254, 255, 255, 255, 255, 255, 255, 255 },
+ { 248, 254, 249, 253, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 246, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 252, 254, 251, 254, 254, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 254, 252, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 248, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 253, 255, 254, 254, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 245, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 253, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 251, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 252, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 252, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 249, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 253, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ },
+ { { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 },
+ { 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255 }
+ }
+ }
+};
+
+void VP8WriteProbas(VP8BitWriter* const bw, const VP8EncProba* const probas) {
+ int t, b, c, p;
+ for (t = 0; t < NUM_TYPES; ++t) {
+ for (b = 0; b < NUM_BANDS; ++b) {
+ for (c = 0; c < NUM_CTX; ++c) {
+ for (p = 0; p < NUM_PROBAS; ++p) {
+ const uint8_t p0 = probas->coeffs_[t][b][c][p];
+ const int update = (p0 != VP8CoeffsProba0[t][b][c][p]);
+ if (VP8PutBit(bw, update, VP8CoeffsUpdateProba[t][b][c][p])) {
+ VP8PutBits(bw, p0, 8);
+ }
+ }
+ }
+ }
+ }
+ if (VP8PutBitUniform(bw, probas->use_skip_proba_)) {
+ VP8PutBits(bw, probas->skip_proba_, 8);
+ }
+}
+
diff --git a/media/libwebp/src/enc/vp8i_enc.h b/media/libwebp/src/enc/vp8i_enc.h
new file mode 100644
index 0000000000..c9927c47d8
--- /dev/null
+++ b/media/libwebp/src/enc/vp8i_enc.h
@@ -0,0 +1,523 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebP encoder: internal header.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_ENC_VP8I_ENC_H_
+#define WEBP_ENC_VP8I_ENC_H_
+
+#include <string.h> // for memcpy()
+#include "src/dec/common_dec.h"
+#include "src/dsp/dsp.h"
+#include "src/utils/bit_writer_utils.h"
+#include "src/utils/thread_utils.h"
+#include "src/utils/utils.h"
+#include "src/webp/encode.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//------------------------------------------------------------------------------
+// Various defines and enums
+
+// version numbers
+#define ENC_MAJ_VERSION 1
+#define ENC_MIN_VERSION 3
+#define ENC_REV_VERSION 0
+
+enum { MAX_LF_LEVELS = 64, // Maximum loop filter level
+ MAX_VARIABLE_LEVEL = 67, // last (inclusive) level with variable cost
+ MAX_LEVEL = 2047 // max level (note: max codable is 2047 + 67)
+ };
+
+typedef enum { // Rate-distortion optimization levels
+ RD_OPT_NONE = 0, // no rd-opt
+ RD_OPT_BASIC = 1, // basic scoring (no trellis)
+ RD_OPT_TRELLIS = 2, // perform trellis-quant on the final decision only
+ RD_OPT_TRELLIS_ALL = 3 // trellis-quant for every scoring (much slower)
+} VP8RDLevel;
+
+// YUV-cache parameters. Cache is 32-bytes wide (= one cacheline).
+// The original or reconstructed samples can be accessed using VP8Scan[].
+// The predicted blocks can be accessed using offsets to yuv_p_ and
+// the arrays VP8*ModeOffsets[].
+// * YUV Samples area (yuv_in_/yuv_out_/yuv_out2_)
+// (see VP8Scan[] for accessing the blocks, along with
+// Y_OFF_ENC/U_OFF_ENC/V_OFF_ENC):
+// +----+----+
+// Y_OFF_ENC |YYYY|UUVV|
+// U_OFF_ENC |YYYY|UUVV|
+// V_OFF_ENC |YYYY|....| <- 25% wasted U/V area
+// |YYYY|....|
+// +----+----+
+// * Prediction area ('yuv_p_', size = PRED_SIZE_ENC)
+// Intra16 predictions (16x16 block each, two per row):
+// |I16DC16|I16TM16|
+// |I16VE16|I16HE16|
+// Chroma U/V predictions (16x8 block each, two per row):
+// |C8DC8|C8TM8|
+// |C8VE8|C8HE8|
+// Intra 4x4 predictions (4x4 block each)
+// |I4DC4 I4TM4 I4VE4 I4HE4|I4RD4 I4VR4 I4LD4 I4VL4|
+// |I4HD4 I4HU4 I4TMP .....|.......................| <- ~31% wasted
+#define YUV_SIZE_ENC (BPS * 16)
+#define PRED_SIZE_ENC (32 * BPS + 16 * BPS + 8 * BPS) // I16+Chroma+I4 preds
+#define Y_OFF_ENC (0)
+#define U_OFF_ENC (16)
+#define V_OFF_ENC (16 + 8)
+
+extern const uint16_t VP8Scan[16];
+extern const uint16_t VP8UVModeOffsets[4];
+extern const uint16_t VP8I16ModeOffsets[4];
+extern const uint16_t VP8I4ModeOffsets[NUM_BMODES];
+
+// Layout of prediction blocks
+// intra 16x16
+#define I16DC16 (0 * 16 * BPS)
+#define I16TM16 (I16DC16 + 16)
+#define I16VE16 (1 * 16 * BPS)
+#define I16HE16 (I16VE16 + 16)
+// chroma 8x8, two U/V blocks side by side (hence: 16x8 each)
+#define C8DC8 (2 * 16 * BPS)
+#define C8TM8 (C8DC8 + 1 * 16)
+#define C8VE8 (2 * 16 * BPS + 8 * BPS)
+#define C8HE8 (C8VE8 + 1 * 16)
+// intra 4x4
+#define I4DC4 (3 * 16 * BPS + 0)
+#define I4TM4 (I4DC4 + 4)
+#define I4VE4 (I4DC4 + 8)
+#define I4HE4 (I4DC4 + 12)
+#define I4RD4 (I4DC4 + 16)
+#define I4VR4 (I4DC4 + 20)
+#define I4LD4 (I4DC4 + 24)
+#define I4VL4 (I4DC4 + 28)
+#define I4HD4 (3 * 16 * BPS + 4 * BPS)
+#define I4HU4 (I4HD4 + 4)
+#define I4TMP (I4HD4 + 8)
+
+typedef int64_t score_t; // type used for scores, rate, distortion
+// Note that MAX_COST is not the maximum allowed by sizeof(score_t),
+// in order to allow overflowing computations.
+#define MAX_COST ((score_t)0x7fffffffffffffLL)
+
+#define QFIX 17
+#define BIAS(b) ((b) << (QFIX - 8))
+// Fun fact: this is the _only_ line where we're actually being lossy and
+// discarding bits.
+static WEBP_INLINE int QUANTDIV(uint32_t n, uint32_t iQ, uint32_t B) {
+ return (int)((n * iQ + B) >> QFIX);
+}
+
+// Uncomment the following to remove token-buffer code:
+// #define DISABLE_TOKEN_BUFFER
+
+// quality below which error-diffusion is enabled
+#define ERROR_DIFFUSION_QUALITY 98
+
+//------------------------------------------------------------------------------
+// Headers
+
+typedef uint32_t proba_t; // 16b + 16b
+typedef uint8_t ProbaArray[NUM_CTX][NUM_PROBAS];
+typedef proba_t StatsArray[NUM_CTX][NUM_PROBAS];
+typedef uint16_t CostArray[NUM_CTX][MAX_VARIABLE_LEVEL + 1];
+typedef const uint16_t* (*CostArrayPtr)[NUM_CTX]; // for easy casting
+typedef const uint16_t* CostArrayMap[16][NUM_CTX];
+typedef double LFStats[NUM_MB_SEGMENTS][MAX_LF_LEVELS]; // filter stats
+
+typedef struct VP8Encoder VP8Encoder;
+
+// segment features
+typedef struct {
+ int num_segments_; // Actual number of segments. 1 segment only = unused.
+ int update_map_; // whether to update the segment map or not.
+ // must be 0 if there's only 1 segment.
+ int size_; // bit-cost for transmitting the segment map
+} VP8EncSegmentHeader;
+
+// Struct collecting all frame-persistent probabilities.
+typedef struct {
+ uint8_t segments_[3]; // probabilities for segment tree
+ uint8_t skip_proba_; // final probability of being skipped.
+ ProbaArray coeffs_[NUM_TYPES][NUM_BANDS]; // 1056 bytes
+ StatsArray stats_[NUM_TYPES][NUM_BANDS]; // 4224 bytes
+ CostArray level_cost_[NUM_TYPES][NUM_BANDS]; // 13056 bytes
+ CostArrayMap remapped_costs_[NUM_TYPES]; // 1536 bytes
+ int dirty_; // if true, need to call VP8CalculateLevelCosts()
+ int use_skip_proba_; // Note: we always use skip_proba for now.
+ int nb_skip_; // number of skipped blocks
+} VP8EncProba;
+
+// Filter parameters. Not actually used in the code (we don't perform
+// the in-loop filtering), but filled from user's config
+typedef struct {
+ int simple_; // filtering type: 0=complex, 1=simple
+ int level_; // base filter level [0..63]
+ int sharpness_; // [0..7]
+ int i4x4_lf_delta_; // delta filter level for i4x4 relative to i16x16
+} VP8EncFilterHeader;
+
+//------------------------------------------------------------------------------
+// Informations about the macroblocks.
+
+typedef struct {
+ // block type
+ unsigned int type_:2; // 0=i4x4, 1=i16x16
+ unsigned int uv_mode_:2;
+ unsigned int skip_:1;
+ unsigned int segment_:2;
+ uint8_t alpha_; // quantization-susceptibility
+} VP8MBInfo;
+
+typedef struct VP8Matrix {
+ uint16_t q_[16]; // quantizer steps
+ uint16_t iq_[16]; // reciprocals, fixed point.
+ uint32_t bias_[16]; // rounding bias
+ uint32_t zthresh_[16]; // value below which a coefficient is zeroed
+ uint16_t sharpen_[16]; // frequency boosters for slight sharpening
+} VP8Matrix;
+
+typedef struct {
+ VP8Matrix y1_, y2_, uv_; // quantization matrices
+ int alpha_; // quant-susceptibility, range [-127,127]. Zero is neutral.
+ // Lower values indicate a lower risk of blurriness.
+ int beta_; // filter-susceptibility, range [0,255].
+ int quant_; // final segment quantizer.
+ int fstrength_; // final in-loop filtering strength
+ int max_edge_; // max edge delta (for filtering strength)
+ int min_disto_; // minimum distortion required to trigger filtering record
+ // reactivities
+ int lambda_i16_, lambda_i4_, lambda_uv_;
+ int lambda_mode_, lambda_trellis_, tlambda_;
+ int lambda_trellis_i16_, lambda_trellis_i4_, lambda_trellis_uv_;
+
+ // lambda values for distortion-based evaluation
+ score_t i4_penalty_; // penalty for using Intra4
+} VP8SegmentInfo;
+
+typedef int8_t DError[2 /* u/v */][2 /* top or left */];
+
+// Handy transient struct to accumulate score and info during RD-optimization
+// and mode evaluation.
+typedef struct {
+ score_t D, SD; // Distortion, spectral distortion
+ score_t H, R, score; // header bits, rate, score.
+ int16_t y_dc_levels[16]; // Quantized levels for luma-DC, luma-AC, chroma.
+ int16_t y_ac_levels[16][16];
+ int16_t uv_levels[4 + 4][16];
+ int mode_i16; // mode number for intra16 prediction
+ uint8_t modes_i4[16]; // mode numbers for intra4 predictions
+ int mode_uv; // mode number of chroma prediction
+ uint32_t nz; // non-zero blocks
+ int8_t derr[2][3]; // DC diffusion errors for U/V for blocks #1/2/3
+} VP8ModeScore;
+
+// Iterator structure to iterate through macroblocks, pointing to the
+// right neighbouring data (samples, predictions, contexts, ...)
+typedef struct {
+ int x_, y_; // current macroblock
+ uint8_t* yuv_in_; // input samples
+ uint8_t* yuv_out_; // output samples
+ uint8_t* yuv_out2_; // secondary buffer swapped with yuv_out_.
+ uint8_t* yuv_p_; // scratch buffer for prediction
+ VP8Encoder* enc_; // back-pointer
+ VP8MBInfo* mb_; // current macroblock
+ VP8BitWriter* bw_; // current bit-writer
+ uint8_t* preds_; // intra mode predictors (4x4 blocks)
+ uint32_t* nz_; // non-zero pattern
+ uint8_t i4_boundary_[37]; // 32+5 boundary samples needed by intra4x4
+ uint8_t* i4_top_; // pointer to the current top boundary sample
+ int i4_; // current intra4x4 mode being tested
+ int top_nz_[9]; // top-non-zero context.
+ int left_nz_[9]; // left-non-zero. left_nz[8] is independent.
+ uint64_t bit_count_[4][3]; // bit counters for coded levels.
+ uint64_t luma_bits_; // macroblock bit-cost for luma
+ uint64_t uv_bits_; // macroblock bit-cost for chroma
+ LFStats* lf_stats_; // filter stats (borrowed from enc_)
+ int do_trellis_; // if true, perform extra level optimisation
+ int count_down_; // number of mb still to be processed
+ int count_down0_; // starting counter value (for progress)
+ int percent0_; // saved initial progress percent
+
+ DError left_derr_; // left error diffusion (u/v)
+ DError* top_derr_; // top diffusion error - NULL if disabled
+
+ uint8_t* y_left_; // left luma samples (addressable from index -1 to 15).
+ uint8_t* u_left_; // left u samples (addressable from index -1 to 7)
+ uint8_t* v_left_; // left v samples (addressable from index -1 to 7)
+
+ uint8_t* y_top_; // top luma samples at position 'x_'
+ uint8_t* uv_top_; // top u/v samples at position 'x_', packed as 16 bytes
+
+ // memory for storing y/u/v_left_
+ uint8_t yuv_left_mem_[17 + 16 + 16 + 8 + WEBP_ALIGN_CST];
+ // memory for yuv_*
+ uint8_t yuv_mem_[3 * YUV_SIZE_ENC + PRED_SIZE_ENC + WEBP_ALIGN_CST];
+} VP8EncIterator;
+
+ // in iterator.c
+// must be called first
+void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it);
+// restart a scan
+void VP8IteratorReset(VP8EncIterator* const it);
+// reset iterator position to row 'y'
+void VP8IteratorSetRow(VP8EncIterator* const it, int y);
+// set count down (=number of iterations to go)
+void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down);
+// return true if iteration is finished
+int VP8IteratorIsDone(const VP8EncIterator* const it);
+// Import uncompressed samples from source.
+// If tmp_32 is not NULL, import boundary samples too.
+// tmp_32 is a 32-bytes scratch buffer that must be aligned in memory.
+void VP8IteratorImport(VP8EncIterator* const it, uint8_t* const tmp_32);
+// export decimated samples
+void VP8IteratorExport(const VP8EncIterator* const it);
+// go to next macroblock. Returns false if not finished.
+int VP8IteratorNext(VP8EncIterator* const it);
+// save the yuv_out_ boundary values to top_/left_ arrays for next iterations.
+void VP8IteratorSaveBoundary(VP8EncIterator* const it);
+// Report progression based on macroblock rows. Return 0 for user-abort request.
+int VP8IteratorProgress(const VP8EncIterator* const it, int delta);
+// Intra4x4 iterations
+void VP8IteratorStartI4(VP8EncIterator* const it);
+// returns true if not done.
+int VP8IteratorRotateI4(VP8EncIterator* const it,
+ const uint8_t* const yuv_out);
+
+// Non-zero context setup/teardown
+void VP8IteratorNzToBytes(VP8EncIterator* const it);
+void VP8IteratorBytesToNz(VP8EncIterator* const it);
+
+// Helper functions to set mode properties
+void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode);
+void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes);
+void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode);
+void VP8SetSkip(const VP8EncIterator* const it, int skip);
+void VP8SetSegment(const VP8EncIterator* const it, int segment);
+
+//------------------------------------------------------------------------------
+// Paginated token buffer
+
+typedef struct VP8Tokens VP8Tokens; // struct details in token.c
+
+typedef struct {
+#if !defined(DISABLE_TOKEN_BUFFER)
+ VP8Tokens* pages_; // first page
+ VP8Tokens** last_page_; // last page
+ uint16_t* tokens_; // set to (*last_page_)->tokens_
+ int left_; // how many free tokens left before the page is full
+ int page_size_; // number of tokens per page
+#endif
+ int error_; // true in case of malloc error
+} VP8TBuffer;
+
+// initialize an empty buffer
+void VP8TBufferInit(VP8TBuffer* const b, int page_size);
+void VP8TBufferClear(VP8TBuffer* const b); // de-allocate pages memory
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+// Finalizes bitstream when probabilities are known.
+// Deletes the allocated token memory if final_pass is true.
+int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
+ const uint8_t* const probas, int final_pass);
+
+// record the coding of coefficients without knowing the probabilities yet
+int VP8RecordCoeffTokens(int ctx, const struct VP8Residual* const res,
+ VP8TBuffer* const tokens);
+
+// Estimate the final coded size given a set of 'probas'.
+size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas);
+
+#endif // !DISABLE_TOKEN_BUFFER
+
+//------------------------------------------------------------------------------
+// VP8Encoder
+
+struct VP8Encoder {
+ const WebPConfig* config_; // user configuration and parameters
+ WebPPicture* pic_; // input / output picture
+
+ // headers
+ VP8EncFilterHeader filter_hdr_; // filtering information
+ VP8EncSegmentHeader segment_hdr_; // segment information
+
+ int profile_; // VP8's profile, deduced from Config.
+
+ // dimension, in macroblock units.
+ int mb_w_, mb_h_;
+ int preds_w_; // stride of the *preds_ prediction plane (=4*mb_w + 1)
+
+ // number of partitions (1, 2, 4 or 8 = MAX_NUM_PARTITIONS)
+ int num_parts_;
+
+ // per-partition boolean decoders.
+ VP8BitWriter bw_; // part0
+ VP8BitWriter parts_[MAX_NUM_PARTITIONS]; // token partitions
+ VP8TBuffer tokens_; // token buffer
+
+ int percent_; // for progress
+
+ // transparency blob
+ int has_alpha_;
+ uint8_t* alpha_data_; // non-NULL if transparency is present
+ uint32_t alpha_data_size_;
+ WebPWorker alpha_worker_;
+
+ // quantization info (one set of DC/AC dequant factor per segment)
+ VP8SegmentInfo dqm_[NUM_MB_SEGMENTS];
+ int base_quant_; // nominal quantizer value. Only used
+ // for relative coding of segments' quant.
+ int alpha_; // global susceptibility (<=> complexity)
+ int uv_alpha_; // U/V quantization susceptibility
+ // global offset of quantizers, shared by all segments
+ int dq_y1_dc_;
+ int dq_y2_dc_, dq_y2_ac_;
+ int dq_uv_dc_, dq_uv_ac_;
+
+ // probabilities and statistics
+ VP8EncProba proba_;
+ uint64_t sse_[4]; // sum of Y/U/V/A squared errors for all macroblocks
+ uint64_t sse_count_; // pixel count for the sse_[] stats
+ int coded_size_;
+ int residual_bytes_[3][4];
+ int block_count_[3];
+
+ // quality/speed settings
+ int method_; // 0=fastest, 6=best/slowest.
+ VP8RDLevel rd_opt_level_; // Deduced from method_.
+ int max_i4_header_bits_; // partition #0 safeness factor
+ int mb_header_limit_; // rough limit for header bits per MB
+ int thread_level_; // derived from config->thread_level
+ int do_search_; // derived from config->target_XXX
+ int use_tokens_; // if true, use token buffer
+
+ // Memory
+ VP8MBInfo* mb_info_; // contextual macroblock infos (mb_w_ + 1)
+ uint8_t* preds_; // predictions modes: (4*mb_w+1) * (4*mb_h+1)
+ uint32_t* nz_; // non-zero bit context: mb_w+1
+ uint8_t* y_top_; // top luma samples.
+ uint8_t* uv_top_; // top u/v samples.
+ // U and V are packed into 16 bytes (8 U + 8 V)
+ LFStats* lf_stats_; // autofilter stats (if NULL, autofilter is off)
+ DError* top_derr_; // diffusion error (NULL if disabled)
+};
+
+//------------------------------------------------------------------------------
+// internal functions. Not public.
+
+ // in tree.c
+extern const uint8_t VP8CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS];
+extern const uint8_t
+ VP8CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS];
+// Reset the token probabilities to their initial (default) values
+void VP8DefaultProbas(VP8Encoder* const enc);
+// Write the token probabilities
+void VP8WriteProbas(VP8BitWriter* const bw, const VP8EncProba* const probas);
+// Writes the partition #0 modes (that is: all intra modes)
+void VP8CodeIntraModes(VP8Encoder* const enc);
+
+ // in syntax.c
+// Generates the final bitstream by coding the partition0 and headers,
+// and appending an assembly of all the pre-coded token partitions.
+// Return true if everything is ok.
+int VP8EncWrite(VP8Encoder* const enc);
+// Release memory allocated for bit-writing in VP8EncLoop & seq.
+void VP8EncFreeBitWriters(VP8Encoder* const enc);
+
+ // in frame.c
+extern const uint8_t VP8Cat3[];
+extern const uint8_t VP8Cat4[];
+extern const uint8_t VP8Cat5[];
+extern const uint8_t VP8Cat6[];
+
+// Form all the four Intra16x16 predictions in the yuv_p_ cache
+void VP8MakeLuma16Preds(const VP8EncIterator* const it);
+// Form all the four Chroma8x8 predictions in the yuv_p_ cache
+void VP8MakeChroma8Preds(const VP8EncIterator* const it);
+// Form all the ten Intra4x4 predictions in the yuv_p_ cache
+// for the 4x4 block it->i4_
+void VP8MakeIntra4Preds(const VP8EncIterator* const it);
+// Rate calculation
+int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd);
+int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]);
+int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd);
+// Main coding calls
+int VP8EncLoop(VP8Encoder* const enc);
+int VP8EncTokenLoop(VP8Encoder* const enc);
+
+ // in webpenc.c
+// Assign an error code to a picture. Return false for convenience.
+int WebPEncodingSetError(const WebPPicture* const pic, WebPEncodingError error);
+int WebPReportProgress(const WebPPicture* const pic,
+ int percent, int* const percent_store);
+
+ // in analysis.c
+// Main analysis loop. Decides the segmentations and complexity.
+// Assigns a first guess for Intra16 and uvmode_ prediction modes.
+int VP8EncAnalyze(VP8Encoder* const enc);
+
+ // in quant.c
+// Sets up segment's quantization values, base_quant_ and filter strengths.
+void VP8SetSegmentParams(VP8Encoder* const enc, float quality);
+// Pick best modes and fills the levels. Returns true if skipped.
+int VP8Decimate(VP8EncIterator* WEBP_RESTRICT const it,
+ VP8ModeScore* WEBP_RESTRICT const rd,
+ VP8RDLevel rd_opt);
+
+ // in alpha.c
+void VP8EncInitAlpha(VP8Encoder* const enc); // initialize alpha compression
+int VP8EncStartAlpha(VP8Encoder* const enc); // start alpha coding process
+int VP8EncFinishAlpha(VP8Encoder* const enc); // finalize compressed data
+int VP8EncDeleteAlpha(VP8Encoder* const enc); // delete compressed data
+
+// autofilter
+void VP8InitFilter(VP8EncIterator* const it);
+void VP8StoreFilterStats(VP8EncIterator* const it);
+void VP8AdjustFilterStrength(VP8EncIterator* const it);
+
+// returns the approximate filtering strength needed to smooth a edge
+// step of 'delta', given a sharpness parameter 'sharpness'.
+int VP8FilterStrengthFromDelta(int sharpness, int delta);
+
+ // misc utils for picture_*.c:
+
+// Returns true if 'picture' is non-NULL and dimensions/colorspace are within
+// their valid ranges. If returning false, the 'error_code' in 'picture' is
+// updated.
+int WebPValidatePicture(const WebPPicture* const picture);
+
+// Remove reference to the ARGB/YUVA buffer (doesn't free anything).
+void WebPPictureResetBuffers(WebPPicture* const picture);
+
+// Allocates ARGB buffer according to set width/height (previous one is
+// always free'd). Preserves the YUV(A) buffer. Returns false in case of error
+// (invalid param, out-of-memory).
+int WebPPictureAllocARGB(WebPPicture* const picture);
+
+// Allocates YUVA buffer according to set width/height (previous one is always
+// free'd). Uses picture->csp to determine whether an alpha buffer is needed.
+// Preserves the ARGB buffer.
+// Returns false in case of error (invalid param, out-of-memory).
+int WebPPictureAllocYUVA(WebPPicture* const picture);
+
+// Replace samples that are fully transparent by 'color' to help compressibility
+// (no guarantee, though). Assumes pic->use_argb is true.
+void WebPReplaceTransparentPixels(WebPPicture* const pic, uint32_t color);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // WEBP_ENC_VP8I_ENC_H_
diff --git a/media/libwebp/src/enc/vp8l_enc.c b/media/libwebp/src/enc/vp8l_enc.c
new file mode 100644
index 0000000000..0b07e529a9
--- /dev/null
+++ b/media/libwebp/src/enc/vp8l_enc.c
@@ -0,0 +1,2198 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// main entry for the lossless encoder.
+//
+// Author: Vikas Arora (vikaas.arora@gmail.com)
+//
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "src/dsp/lossless.h"
+#include "src/dsp/lossless_common.h"
+#include "src/enc/backward_references_enc.h"
+#include "src/enc/histogram_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/enc/vp8li_enc.h"
+#include "src/utils/bit_writer_utils.h"
+#include "src/utils/huffman_encode_utils.h"
+#include "src/utils/utils.h"
+#include "src/webp/encode.h"
+#include "src/webp/format_constants.h"
+
+// Maximum number of histogram images (sub-blocks).
+#define MAX_HUFF_IMAGE_SIZE 2600
+
+// Palette reordering for smaller sum of deltas (and for smaller storage).
+
+static int PaletteCompareColorsForQsort(const void* p1, const void* p2) {
+ const uint32_t a = WebPMemToUint32((uint8_t*)p1);
+ const uint32_t b = WebPMemToUint32((uint8_t*)p2);
+ assert(a != b);
+ return (a < b) ? -1 : 1;
+}
+
+static WEBP_INLINE uint32_t PaletteComponentDistance(uint32_t v) {
+ return (v <= 128) ? v : (256 - v);
+}
+
+// Computes a value that is related to the entropy created by the
+// palette entry diff.
+//
+// Note that the last & 0xff is a no-operation in the next statement, but
+// removed by most compilers and is here only for regularity of the code.
+static WEBP_INLINE uint32_t PaletteColorDistance(uint32_t col1, uint32_t col2) {
+ const uint32_t diff = VP8LSubPixels(col1, col2);
+ const int kMoreWeightForRGBThanForAlpha = 9;
+ uint32_t score;
+ score = PaletteComponentDistance((diff >> 0) & 0xff);
+ score += PaletteComponentDistance((diff >> 8) & 0xff);
+ score += PaletteComponentDistance((diff >> 16) & 0xff);
+ score *= kMoreWeightForRGBThanForAlpha;
+ score += PaletteComponentDistance((diff >> 24) & 0xff);
+ return score;
+}
+
+static WEBP_INLINE void SwapColor(uint32_t* const col1, uint32_t* const col2) {
+ const uint32_t tmp = *col1;
+ *col1 = *col2;
+ *col2 = tmp;
+}
+
+static WEBP_INLINE int SearchColorNoIdx(const uint32_t sorted[], uint32_t color,
+ int num_colors) {
+ int low = 0, hi = num_colors;
+ if (sorted[low] == color) return low; // loop invariant: sorted[low] != color
+ while (1) {
+ const int mid = (low + hi) >> 1;
+ if (sorted[mid] == color) {
+ return mid;
+ } else if (sorted[mid] < color) {
+ low = mid;
+ } else {
+ hi = mid;
+ }
+ }
+ assert(0);
+ return 0;
+}
+
+// The palette has been sorted by alpha. This function checks if the other
+// components of the palette have a monotonic development with regards to
+// position in the palette. If all have monotonic development, there is
+// no benefit to re-organize them greedily. A monotonic development
+// would be spotted in green-only situations (like lossy alpha) or gray-scale
+// images.
+static int PaletteHasNonMonotonousDeltas(const uint32_t* const palette,
+ int num_colors) {
+ uint32_t predict = 0x000000;
+ int i;
+ uint8_t sign_found = 0x00;
+ for (i = 0; i < num_colors; ++i) {
+ const uint32_t diff = VP8LSubPixels(palette[i], predict);
+ const uint8_t rd = (diff >> 16) & 0xff;
+ const uint8_t gd = (diff >> 8) & 0xff;
+ const uint8_t bd = (diff >> 0) & 0xff;
+ if (rd != 0x00) {
+ sign_found |= (rd < 0x80) ? 1 : 2;
+ }
+ if (gd != 0x00) {
+ sign_found |= (gd < 0x80) ? 8 : 16;
+ }
+ if (bd != 0x00) {
+ sign_found |= (bd < 0x80) ? 64 : 128;
+ }
+ predict = palette[i];
+ }
+ return (sign_found & (sign_found << 1)) != 0; // two consequent signs.
+}
+
+static void PaletteSortMinimizeDeltas(const uint32_t* const palette_sorted,
+ int num_colors, uint32_t* const palette) {
+ uint32_t predict = 0x00000000;
+ int i, k;
+ memcpy(palette, palette_sorted, num_colors * sizeof(*palette));
+ if (!PaletteHasNonMonotonousDeltas(palette_sorted, num_colors)) return;
+ // Find greedily always the closest color of the predicted color to minimize
+ // deltas in the palette. This reduces storage needs since the
+ // palette is stored with delta encoding.
+ for (i = 0; i < num_colors; ++i) {
+ int best_ix = i;
+ uint32_t best_score = ~0U;
+ for (k = i; k < num_colors; ++k) {
+ const uint32_t cur_score = PaletteColorDistance(palette[k], predict);
+ if (best_score > cur_score) {
+ best_score = cur_score;
+ best_ix = k;
+ }
+ }
+ SwapColor(&palette[best_ix], &palette[i]);
+ predict = palette[i];
+ }
+}
+
+// Sort palette in increasing order and prepare an inverse mapping array.
+static void PrepareMapToPalette(const uint32_t palette[], uint32_t num_colors,
+ uint32_t sorted[], uint32_t idx_map[]) {
+ uint32_t i;
+ memcpy(sorted, palette, num_colors * sizeof(*sorted));
+ qsort(sorted, num_colors, sizeof(*sorted), PaletteCompareColorsForQsort);
+ for (i = 0; i < num_colors; ++i) {
+ idx_map[SearchColorNoIdx(sorted, palette[i], num_colors)] = i;
+ }
+}
+
+// -----------------------------------------------------------------------------
+// Modified Zeng method from "A Survey on Palette Reordering
+// Methods for Improving the Compression of Color-Indexed Images" by Armando J.
+// Pinho and Antonio J. R. Neves.
+
+// Finds the biggest cooccurrence in the matrix.
+static void CoOccurrenceFindMax(const uint32_t* const cooccurrence,
+ uint32_t num_colors, uint8_t* const c1,
+ uint8_t* const c2) {
+ // Find the index that is most frequently located adjacent to other
+ // (different) indexes.
+ uint32_t best_sum = 0u;
+ uint32_t i, j, best_cooccurrence;
+ *c1 = 0u;
+ for (i = 0; i < num_colors; ++i) {
+ uint32_t sum = 0;
+ for (j = 0; j < num_colors; ++j) sum += cooccurrence[i * num_colors + j];
+ if (sum > best_sum) {
+ best_sum = sum;
+ *c1 = i;
+ }
+ }
+ // Find the index that is most frequently found adjacent to *c1.
+ *c2 = 0u;
+ best_cooccurrence = 0u;
+ for (i = 0; i < num_colors; ++i) {
+ if (cooccurrence[*c1 * num_colors + i] > best_cooccurrence) {
+ best_cooccurrence = cooccurrence[*c1 * num_colors + i];
+ *c2 = i;
+ }
+ }
+ assert(*c1 != *c2);
+}
+
+// Builds the cooccurrence matrix
+static int CoOccurrenceBuild(const WebPPicture* const pic,
+ const uint32_t* const palette, uint32_t num_colors,
+ uint32_t* cooccurrence) {
+ uint32_t *lines, *line_top, *line_current, *line_tmp;
+ int x, y;
+ const uint32_t* src = pic->argb;
+ uint32_t prev_pix = ~src[0];
+ uint32_t prev_idx = 0u;
+ uint32_t idx_map[MAX_PALETTE_SIZE] = {0};
+ uint32_t palette_sorted[MAX_PALETTE_SIZE];
+ lines = (uint32_t*)WebPSafeMalloc(2 * pic->width, sizeof(*lines));
+ if (lines == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ line_top = &lines[0];
+ line_current = &lines[pic->width];
+ PrepareMapToPalette(palette, num_colors, palette_sorted, idx_map);
+ for (y = 0; y < pic->height; ++y) {
+ for (x = 0; x < pic->width; ++x) {
+ const uint32_t pix = src[x];
+ if (pix != prev_pix) {
+ prev_idx = idx_map[SearchColorNoIdx(palette_sorted, pix, num_colors)];
+ prev_pix = pix;
+ }
+ line_current[x] = prev_idx;
+ // 4-connectivity is what works best as mentioned in "On the relation
+ // between Memon's and the modified Zeng's palette reordering methods".
+ if (x > 0 && prev_idx != line_current[x - 1]) {
+ const uint32_t left_idx = line_current[x - 1];
+ ++cooccurrence[prev_idx * num_colors + left_idx];
+ ++cooccurrence[left_idx * num_colors + prev_idx];
+ }
+ if (y > 0 && prev_idx != line_top[x]) {
+ const uint32_t top_idx = line_top[x];
+ ++cooccurrence[prev_idx * num_colors + top_idx];
+ ++cooccurrence[top_idx * num_colors + prev_idx];
+ }
+ }
+ line_tmp = line_top;
+ line_top = line_current;
+ line_current = line_tmp;
+ src += pic->argb_stride;
+ }
+ WebPSafeFree(lines);
+ return 1;
+}
+
+struct Sum {
+ uint8_t index;
+ uint32_t sum;
+};
+
+// Implements the modified Zeng method from "A Survey on Palette Reordering
+// Methods for Improving the Compression of Color-Indexed Images" by Armando J.
+// Pinho and Antonio J. R. Neves.
+static int PaletteSortModifiedZeng(
+ const WebPPicture* const pic, const uint32_t* const palette_sorted,
+ uint32_t num_colors, uint32_t* const palette) {
+ uint32_t i, j, ind;
+ uint8_t remapping[MAX_PALETTE_SIZE];
+ uint32_t* cooccurrence;
+ struct Sum sums[MAX_PALETTE_SIZE];
+ uint32_t first, last;
+ uint32_t num_sums;
+ // TODO(vrabaud) check whether one color images should use palette or not.
+ if (num_colors <= 1) return 1;
+ // Build the co-occurrence matrix.
+ cooccurrence =
+ (uint32_t*)WebPSafeCalloc(num_colors * num_colors, sizeof(*cooccurrence));
+ if (cooccurrence == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ if (!CoOccurrenceBuild(pic, palette_sorted, num_colors, cooccurrence)) {
+ return 0;
+ }
+
+ // Initialize the mapping list with the two best indices.
+ CoOccurrenceFindMax(cooccurrence, num_colors, &remapping[0], &remapping[1]);
+
+ // We need to append and prepend to the list of remapping. To this end, we
+ // actually define the next start/end of the list as indices in a vector (with
+ // a wrap around when the end is reached).
+ first = 0;
+ last = 1;
+ num_sums = num_colors - 2; // -2 because we know the first two values
+ if (num_sums > 0) {
+ // Initialize the sums with the first two remappings and find the best one
+ struct Sum* best_sum = &sums[0];
+ best_sum->index = 0u;
+ best_sum->sum = 0u;
+ for (i = 0, j = 0; i < num_colors; ++i) {
+ if (i == remapping[0] || i == remapping[1]) continue;
+ sums[j].index = i;
+ sums[j].sum = cooccurrence[i * num_colors + remapping[0]] +
+ cooccurrence[i * num_colors + remapping[1]];
+ if (sums[j].sum > best_sum->sum) best_sum = &sums[j];
+ ++j;
+ }
+
+ while (num_sums > 0) {
+ const uint8_t best_index = best_sum->index;
+ // Compute delta to know if we need to prepend or append the best index.
+ int32_t delta = 0;
+ const int32_t n = num_colors - num_sums;
+ for (ind = first, j = 0; (ind + j) % num_colors != last + 1; ++j) {
+ const uint16_t l_j = remapping[(ind + j) % num_colors];
+ delta += (n - 1 - 2 * (int32_t)j) *
+ (int32_t)cooccurrence[best_index * num_colors + l_j];
+ }
+ if (delta > 0) {
+ first = (first == 0) ? num_colors - 1 : first - 1;
+ remapping[first] = best_index;
+ } else {
+ ++last;
+ remapping[last] = best_index;
+ }
+ // Remove best_sum from sums.
+ *best_sum = sums[num_sums - 1];
+ --num_sums;
+ // Update all the sums and find the best one.
+ best_sum = &sums[0];
+ for (i = 0; i < num_sums; ++i) {
+ sums[i].sum += cooccurrence[best_index * num_colors + sums[i].index];
+ if (sums[i].sum > best_sum->sum) best_sum = &sums[i];
+ }
+ }
+ }
+ assert((last + 1) % num_colors == first);
+ WebPSafeFree(cooccurrence);
+
+ // Re-map the palette.
+ for (i = 0; i < num_colors; ++i) {
+ palette[i] = palette_sorted[remapping[(first + i) % num_colors]];
+ }
+ return 1;
+}
+
+// -----------------------------------------------------------------------------
+// Palette
+
+// These five modes are evaluated and their respective entropy is computed.
+typedef enum {
+ kDirect = 0,
+ kSpatial = 1,
+ kSubGreen = 2,
+ kSpatialSubGreen = 3,
+ kPalette = 4,
+ kPaletteAndSpatial = 5,
+ kNumEntropyIx = 6
+} EntropyIx;
+
+typedef enum {
+ kSortedDefault = 0,
+ kMinimizeDelta = 1,
+ kModifiedZeng = 2,
+ kUnusedPalette = 3,
+} PaletteSorting;
+
+typedef enum {
+ kHistoAlpha = 0,
+ kHistoAlphaPred,
+ kHistoGreen,
+ kHistoGreenPred,
+ kHistoRed,
+ kHistoRedPred,
+ kHistoBlue,
+ kHistoBluePred,
+ kHistoRedSubGreen,
+ kHistoRedPredSubGreen,
+ kHistoBlueSubGreen,
+ kHistoBluePredSubGreen,
+ kHistoPalette,
+ kHistoTotal // Must be last.
+} HistoIx;
+
+static void AddSingleSubGreen(uint32_t p,
+ uint32_t* const r, uint32_t* const b) {
+ const int green = (int)p >> 8; // The upper bits are masked away later.
+ ++r[(((int)p >> 16) - green) & 0xff];
+ ++b[(((int)p >> 0) - green) & 0xff];
+}
+
+static void AddSingle(uint32_t p,
+ uint32_t* const a, uint32_t* const r,
+ uint32_t* const g, uint32_t* const b) {
+ ++a[(p >> 24) & 0xff];
+ ++r[(p >> 16) & 0xff];
+ ++g[(p >> 8) & 0xff];
+ ++b[(p >> 0) & 0xff];
+}
+
+static WEBP_INLINE uint32_t HashPix(uint32_t pix) {
+ // Note that masking with 0xffffffffu is for preventing an
+ // 'unsigned int overflow' warning. Doesn't impact the compiled code.
+ return ((((uint64_t)pix + (pix >> 19)) * 0x39c5fba7ull) & 0xffffffffu) >> 24;
+}
+
+static int AnalyzeEntropy(const uint32_t* argb,
+ int width, int height, int argb_stride,
+ int use_palette,
+ int palette_size, int transform_bits,
+ EntropyIx* const min_entropy_ix,
+ int* const red_and_blue_always_zero) {
+ // Allocate histogram set with cache_bits = 0.
+ uint32_t* histo;
+
+ if (use_palette && palette_size <= 16) {
+ // In the case of small palettes, we pack 2, 4 or 8 pixels together. In
+ // practice, small palettes are better than any other transform.
+ *min_entropy_ix = kPalette;
+ *red_and_blue_always_zero = 1;
+ return 1;
+ }
+ histo = (uint32_t*)WebPSafeCalloc(kHistoTotal, sizeof(*histo) * 256);
+ if (histo != NULL) {
+ int i, x, y;
+ const uint32_t* prev_row = NULL;
+ const uint32_t* curr_row = argb;
+ uint32_t pix_prev = argb[0]; // Skip the first pixel.
+ for (y = 0; y < height; ++y) {
+ for (x = 0; x < width; ++x) {
+ const uint32_t pix = curr_row[x];
+ const uint32_t pix_diff = VP8LSubPixels(pix, pix_prev);
+ pix_prev = pix;
+ if ((pix_diff == 0) || (prev_row != NULL && pix == prev_row[x])) {
+ continue;
+ }
+ AddSingle(pix,
+ &histo[kHistoAlpha * 256],
+ &histo[kHistoRed * 256],
+ &histo[kHistoGreen * 256],
+ &histo[kHistoBlue * 256]);
+ AddSingle(pix_diff,
+ &histo[kHistoAlphaPred * 256],
+ &histo[kHistoRedPred * 256],
+ &histo[kHistoGreenPred * 256],
+ &histo[kHistoBluePred * 256]);
+ AddSingleSubGreen(pix,
+ &histo[kHistoRedSubGreen * 256],
+ &histo[kHistoBlueSubGreen * 256]);
+ AddSingleSubGreen(pix_diff,
+ &histo[kHistoRedPredSubGreen * 256],
+ &histo[kHistoBluePredSubGreen * 256]);
+ {
+ // Approximate the palette by the entropy of the multiplicative hash.
+ const uint32_t hash = HashPix(pix);
+ ++histo[kHistoPalette * 256 + hash];
+ }
+ }
+ prev_row = curr_row;
+ curr_row += argb_stride;
+ }
+ {
+ float entropy_comp[kHistoTotal];
+ float entropy[kNumEntropyIx];
+ int k;
+ int last_mode_to_analyze = use_palette ? kPalette : kSpatialSubGreen;
+ int j;
+ // Let's add one zero to the predicted histograms. The zeros are removed
+ // too efficiently by the pix_diff == 0 comparison, at least one of the
+ // zeros is likely to exist.
+ ++histo[kHistoRedPredSubGreen * 256];
+ ++histo[kHistoBluePredSubGreen * 256];
+ ++histo[kHistoRedPred * 256];
+ ++histo[kHistoGreenPred * 256];
+ ++histo[kHistoBluePred * 256];
+ ++histo[kHistoAlphaPred * 256];
+
+ for (j = 0; j < kHistoTotal; ++j) {
+ entropy_comp[j] = VP8LBitsEntropy(&histo[j * 256], 256);
+ }
+ entropy[kDirect] = entropy_comp[kHistoAlpha] +
+ entropy_comp[kHistoRed] +
+ entropy_comp[kHistoGreen] +
+ entropy_comp[kHistoBlue];
+ entropy[kSpatial] = entropy_comp[kHistoAlphaPred] +
+ entropy_comp[kHistoRedPred] +
+ entropy_comp[kHistoGreenPred] +
+ entropy_comp[kHistoBluePred];
+ entropy[kSubGreen] = entropy_comp[kHistoAlpha] +
+ entropy_comp[kHistoRedSubGreen] +
+ entropy_comp[kHistoGreen] +
+ entropy_comp[kHistoBlueSubGreen];
+ entropy[kSpatialSubGreen] = entropy_comp[kHistoAlphaPred] +
+ entropy_comp[kHistoRedPredSubGreen] +
+ entropy_comp[kHistoGreenPred] +
+ entropy_comp[kHistoBluePredSubGreen];
+ entropy[kPalette] = entropy_comp[kHistoPalette];
+
+ // When including transforms, there is an overhead in bits from
+ // storing them. This overhead is small but matters for small images.
+ // For spatial, there are 14 transformations.
+ entropy[kSpatial] += VP8LSubSampleSize(width, transform_bits) *
+ VP8LSubSampleSize(height, transform_bits) *
+ VP8LFastLog2(14);
+ // For color transforms: 24 as only 3 channels are considered in a
+ // ColorTransformElement.
+ entropy[kSpatialSubGreen] += VP8LSubSampleSize(width, transform_bits) *
+ VP8LSubSampleSize(height, transform_bits) *
+ VP8LFastLog2(24);
+ // For palettes, add the cost of storing the palette.
+ // We empirically estimate the cost of a compressed entry as 8 bits.
+ // The palette is differential-coded when compressed hence a much
+ // lower cost than sizeof(uint32_t)*8.
+ entropy[kPalette] += palette_size * 8;
+
+ *min_entropy_ix = kDirect;
+ for (k = kDirect + 1; k <= last_mode_to_analyze; ++k) {
+ if (entropy[*min_entropy_ix] > entropy[k]) {
+ *min_entropy_ix = (EntropyIx)k;
+ }
+ }
+ assert((int)*min_entropy_ix <= last_mode_to_analyze);
+ *red_and_blue_always_zero = 1;
+ // Let's check if the histogram of the chosen entropy mode has
+ // non-zero red and blue values. If all are zero, we can later skip
+ // the cross color optimization.
+ {
+ static const uint8_t kHistoPairs[5][2] = {
+ { kHistoRed, kHistoBlue },
+ { kHistoRedPred, kHistoBluePred },
+ { kHistoRedSubGreen, kHistoBlueSubGreen },
+ { kHistoRedPredSubGreen, kHistoBluePredSubGreen },
+ { kHistoRed, kHistoBlue }
+ };
+ const uint32_t* const red_histo =
+ &histo[256 * kHistoPairs[*min_entropy_ix][0]];
+ const uint32_t* const blue_histo =
+ &histo[256 * kHistoPairs[*min_entropy_ix][1]];
+ for (i = 1; i < 256; ++i) {
+ if ((red_histo[i] | blue_histo[i]) != 0) {
+ *red_and_blue_always_zero = 0;
+ break;
+ }
+ }
+ }
+ }
+ WebPSafeFree(histo);
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+static int GetHistoBits(int method, int use_palette, int width, int height) {
+ // Make tile size a function of encoding method (Range: 0 to 6).
+ int histo_bits = (use_palette ? 9 : 7) - method;
+ while (1) {
+ const int huff_image_size = VP8LSubSampleSize(width, histo_bits) *
+ VP8LSubSampleSize(height, histo_bits);
+ if (huff_image_size <= MAX_HUFF_IMAGE_SIZE) break;
+ ++histo_bits;
+ }
+ return (histo_bits < MIN_HUFFMAN_BITS) ? MIN_HUFFMAN_BITS :
+ (histo_bits > MAX_HUFFMAN_BITS) ? MAX_HUFFMAN_BITS : histo_bits;
+}
+
+static int GetTransformBits(int method, int histo_bits) {
+ const int max_transform_bits = (method < 4) ? 6 : (method > 4) ? 4 : 5;
+ const int res =
+ (histo_bits > max_transform_bits) ? max_transform_bits : histo_bits;
+ assert(res <= MAX_TRANSFORM_BITS);
+ return res;
+}
+
+// Set of parameters to be used in each iteration of the cruncher.
+#define CRUNCH_SUBCONFIGS_MAX 2
+typedef struct {
+ int lz77_;
+ int do_no_cache_;
+} CrunchSubConfig;
+typedef struct {
+ int entropy_idx_;
+ PaletteSorting palette_sorting_type_;
+ CrunchSubConfig sub_configs_[CRUNCH_SUBCONFIGS_MAX];
+ int sub_configs_size_;
+} CrunchConfig;
+
+// +2 because we add a palette sorting configuration for kPalette and
+// kPaletteAndSpatial.
+#define CRUNCH_CONFIGS_MAX (kNumEntropyIx + 2)
+
+static int EncoderAnalyze(VP8LEncoder* const enc,
+ CrunchConfig crunch_configs[CRUNCH_CONFIGS_MAX],
+ int* const crunch_configs_size,
+ int* const red_and_blue_always_zero) {
+ const WebPPicture* const pic = enc->pic_;
+ const int width = pic->width;
+ const int height = pic->height;
+ const WebPConfig* const config = enc->config_;
+ const int method = config->method;
+ const int low_effort = (config->method == 0);
+ int i;
+ int use_palette;
+ int n_lz77s;
+ // If set to 0, analyze the cache with the computed cache value. If 1, also
+ // analyze with no-cache.
+ int do_no_cache = 0;
+ assert(pic != NULL && pic->argb != NULL);
+
+ // Check whether a palette is possible.
+ enc->palette_size_ = WebPGetColorPalette(pic, enc->palette_sorted_);
+ use_palette = (enc->palette_size_ <= MAX_PALETTE_SIZE);
+ if (!use_palette) {
+ enc->palette_size_ = 0;
+ } else {
+ qsort(enc->palette_sorted_, enc->palette_size_,
+ sizeof(*enc->palette_sorted_), PaletteCompareColorsForQsort);
+ }
+
+ // Empirical bit sizes.
+ enc->histo_bits_ = GetHistoBits(method, use_palette,
+ pic->width, pic->height);
+ enc->transform_bits_ = GetTransformBits(method, enc->histo_bits_);
+
+ if (low_effort) {
+ // AnalyzeEntropy is somewhat slow.
+ crunch_configs[0].entropy_idx_ = use_palette ? kPalette : kSpatialSubGreen;
+ crunch_configs[0].palette_sorting_type_ =
+ use_palette ? kSortedDefault : kUnusedPalette;
+ n_lz77s = 1;
+ *crunch_configs_size = 1;
+ } else {
+ EntropyIx min_entropy_ix;
+ // Try out multiple LZ77 on images with few colors.
+ n_lz77s = (enc->palette_size_ > 0 && enc->palette_size_ <= 16) ? 2 : 1;
+ if (!AnalyzeEntropy(pic->argb, width, height, pic->argb_stride, use_palette,
+ enc->palette_size_, enc->transform_bits_,
+ &min_entropy_ix, red_and_blue_always_zero)) {
+ return 0;
+ }
+ if (method == 6 && config->quality == 100) {
+ do_no_cache = 1;
+ // Go brute force on all transforms.
+ *crunch_configs_size = 0;
+ for (i = 0; i < kNumEntropyIx; ++i) {
+ // We can only apply kPalette or kPaletteAndSpatial if we can indeed use
+ // a palette.
+ if ((i != kPalette && i != kPaletteAndSpatial) || use_palette) {
+ assert(*crunch_configs_size < CRUNCH_CONFIGS_MAX);
+ crunch_configs[(*crunch_configs_size)].entropy_idx_ = i;
+ if (use_palette && (i == kPalette || i == kPaletteAndSpatial)) {
+ crunch_configs[(*crunch_configs_size)].palette_sorting_type_ =
+ kMinimizeDelta;
+ ++*crunch_configs_size;
+ // Also add modified Zeng's method.
+ crunch_configs[(*crunch_configs_size)].entropy_idx_ = i;
+ crunch_configs[(*crunch_configs_size)].palette_sorting_type_ =
+ kModifiedZeng;
+ } else {
+ crunch_configs[(*crunch_configs_size)].palette_sorting_type_ =
+ kUnusedPalette;
+ }
+ ++*crunch_configs_size;
+ }
+ }
+ } else {
+ // Only choose the guessed best transform.
+ *crunch_configs_size = 1;
+ crunch_configs[0].entropy_idx_ = min_entropy_ix;
+ crunch_configs[0].palette_sorting_type_ =
+ use_palette ? kMinimizeDelta : kUnusedPalette;
+ if (config->quality >= 75 && method == 5) {
+ // Test with and without color cache.
+ do_no_cache = 1;
+ // If we have a palette, also check in combination with spatial.
+ if (min_entropy_ix == kPalette) {
+ *crunch_configs_size = 2;
+ crunch_configs[1].entropy_idx_ = kPaletteAndSpatial;
+ crunch_configs[1].palette_sorting_type_ = kMinimizeDelta;
+ }
+ }
+ }
+ }
+ // Fill in the different LZ77s.
+ assert(n_lz77s <= CRUNCH_SUBCONFIGS_MAX);
+ for (i = 0; i < *crunch_configs_size; ++i) {
+ int j;
+ for (j = 0; j < n_lz77s; ++j) {
+ assert(j < CRUNCH_SUBCONFIGS_MAX);
+ crunch_configs[i].sub_configs_[j].lz77_ =
+ (j == 0) ? kLZ77Standard | kLZ77RLE : kLZ77Box;
+ crunch_configs[i].sub_configs_[j].do_no_cache_ = do_no_cache;
+ }
+ crunch_configs[i].sub_configs_size_ = n_lz77s;
+ }
+ return 1;
+}
+
+static int EncoderInit(VP8LEncoder* const enc) {
+ const WebPPicture* const pic = enc->pic_;
+ const int width = pic->width;
+ const int height = pic->height;
+ const int pix_cnt = width * height;
+ // we round the block size up, so we're guaranteed to have
+ // at most MAX_REFS_BLOCK_PER_IMAGE blocks used:
+ const int refs_block_size = (pix_cnt - 1) / MAX_REFS_BLOCK_PER_IMAGE + 1;
+ int i;
+ if (!VP8LHashChainInit(&enc->hash_chain_, pix_cnt)) return 0;
+
+ for (i = 0; i < 4; ++i) VP8LBackwardRefsInit(&enc->refs_[i], refs_block_size);
+
+ return 1;
+}
+
+// Returns false in case of memory error.
+static int GetHuffBitLengthsAndCodes(
+ const VP8LHistogramSet* const histogram_image,
+ HuffmanTreeCode* const huffman_codes) {
+ int i, k;
+ int ok = 0;
+ uint64_t total_length_size = 0;
+ uint8_t* mem_buf = NULL;
+ const int histogram_image_size = histogram_image->size;
+ int max_num_symbols = 0;
+ uint8_t* buf_rle = NULL;
+ HuffmanTree* huff_tree = NULL;
+
+ // Iterate over all histograms and get the aggregate number of codes used.
+ for (i = 0; i < histogram_image_size; ++i) {
+ const VP8LHistogram* const histo = histogram_image->histograms[i];
+ HuffmanTreeCode* const codes = &huffman_codes[5 * i];
+ assert(histo != NULL);
+ for (k = 0; k < 5; ++k) {
+ const int num_symbols =
+ (k == 0) ? VP8LHistogramNumCodes(histo->palette_code_bits_) :
+ (k == 4) ? NUM_DISTANCE_CODES : 256;
+ codes[k].num_symbols = num_symbols;
+ total_length_size += num_symbols;
+ }
+ }
+
+ // Allocate and Set Huffman codes.
+ {
+ uint16_t* codes;
+ uint8_t* lengths;
+ mem_buf = (uint8_t*)WebPSafeCalloc(total_length_size,
+ sizeof(*lengths) + sizeof(*codes));
+ if (mem_buf == NULL) goto End;
+
+ codes = (uint16_t*)mem_buf;
+ lengths = (uint8_t*)&codes[total_length_size];
+ for (i = 0; i < 5 * histogram_image_size; ++i) {
+ const int bit_length = huffman_codes[i].num_symbols;
+ huffman_codes[i].codes = codes;
+ huffman_codes[i].code_lengths = lengths;
+ codes += bit_length;
+ lengths += bit_length;
+ if (max_num_symbols < bit_length) {
+ max_num_symbols = bit_length;
+ }
+ }
+ }
+
+ buf_rle = (uint8_t*)WebPSafeMalloc(1ULL, max_num_symbols);
+ huff_tree = (HuffmanTree*)WebPSafeMalloc(3ULL * max_num_symbols,
+ sizeof(*huff_tree));
+ if (buf_rle == NULL || huff_tree == NULL) goto End;
+
+ // Create Huffman trees.
+ for (i = 0; i < histogram_image_size; ++i) {
+ HuffmanTreeCode* const codes = &huffman_codes[5 * i];
+ VP8LHistogram* const histo = histogram_image->histograms[i];
+ VP8LCreateHuffmanTree(histo->literal_, 15, buf_rle, huff_tree, codes + 0);
+ VP8LCreateHuffmanTree(histo->red_, 15, buf_rle, huff_tree, codes + 1);
+ VP8LCreateHuffmanTree(histo->blue_, 15, buf_rle, huff_tree, codes + 2);
+ VP8LCreateHuffmanTree(histo->alpha_, 15, buf_rle, huff_tree, codes + 3);
+ VP8LCreateHuffmanTree(histo->distance_, 15, buf_rle, huff_tree, codes + 4);
+ }
+ ok = 1;
+ End:
+ WebPSafeFree(huff_tree);
+ WebPSafeFree(buf_rle);
+ if (!ok) {
+ WebPSafeFree(mem_buf);
+ memset(huffman_codes, 0, 5 * histogram_image_size * sizeof(*huffman_codes));
+ }
+ return ok;
+}
+
+static void StoreHuffmanTreeOfHuffmanTreeToBitMask(
+ VP8LBitWriter* const bw, const uint8_t* code_length_bitdepth) {
+ // RFC 1951 will calm you down if you are worried about this funny sequence.
+ // This sequence is tuned from that, but more weighted for lower symbol count,
+ // and more spiking histograms.
+ static const uint8_t kStorageOrder[CODE_LENGTH_CODES] = {
+ 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+ };
+ int i;
+ // Throw away trailing zeros:
+ int codes_to_store = CODE_LENGTH_CODES;
+ for (; codes_to_store > 4; --codes_to_store) {
+ if (code_length_bitdepth[kStorageOrder[codes_to_store - 1]] != 0) {
+ break;
+ }
+ }
+ VP8LPutBits(bw, codes_to_store - 4, 4);
+ for (i = 0; i < codes_to_store; ++i) {
+ VP8LPutBits(bw, code_length_bitdepth[kStorageOrder[i]], 3);
+ }
+}
+
+static void ClearHuffmanTreeIfOnlyOneSymbol(
+ HuffmanTreeCode* const huffman_code) {
+ int k;
+ int count = 0;
+ for (k = 0; k < huffman_code->num_symbols; ++k) {
+ if (huffman_code->code_lengths[k] != 0) {
+ ++count;
+ if (count > 1) return;
+ }
+ }
+ for (k = 0; k < huffman_code->num_symbols; ++k) {
+ huffman_code->code_lengths[k] = 0;
+ huffman_code->codes[k] = 0;
+ }
+}
+
+static void StoreHuffmanTreeToBitMask(
+ VP8LBitWriter* const bw,
+ const HuffmanTreeToken* const tokens, const int num_tokens,
+ const HuffmanTreeCode* const huffman_code) {
+ int i;
+ for (i = 0; i < num_tokens; ++i) {
+ const int ix = tokens[i].code;
+ const int extra_bits = tokens[i].extra_bits;
+ VP8LPutBits(bw, huffman_code->codes[ix], huffman_code->code_lengths[ix]);
+ switch (ix) {
+ case 16:
+ VP8LPutBits(bw, extra_bits, 2);
+ break;
+ case 17:
+ VP8LPutBits(bw, extra_bits, 3);
+ break;
+ case 18:
+ VP8LPutBits(bw, extra_bits, 7);
+ break;
+ }
+ }
+}
+
+// 'huff_tree' and 'tokens' are pre-alloacted buffers.
+static void StoreFullHuffmanCode(VP8LBitWriter* const bw,
+ HuffmanTree* const huff_tree,
+ HuffmanTreeToken* const tokens,
+ const HuffmanTreeCode* const tree) {
+ uint8_t code_length_bitdepth[CODE_LENGTH_CODES] = { 0 };
+ uint16_t code_length_bitdepth_symbols[CODE_LENGTH_CODES] = { 0 };
+ const int max_tokens = tree->num_symbols;
+ int num_tokens;
+ HuffmanTreeCode huffman_code;
+ huffman_code.num_symbols = CODE_LENGTH_CODES;
+ huffman_code.code_lengths = code_length_bitdepth;
+ huffman_code.codes = code_length_bitdepth_symbols;
+
+ VP8LPutBits(bw, 0, 1);
+ num_tokens = VP8LCreateCompressedHuffmanTree(tree, tokens, max_tokens);
+ {
+ uint32_t histogram[CODE_LENGTH_CODES] = { 0 };
+ uint8_t buf_rle[CODE_LENGTH_CODES] = { 0 };
+ int i;
+ for (i = 0; i < num_tokens; ++i) {
+ ++histogram[tokens[i].code];
+ }
+
+ VP8LCreateHuffmanTree(histogram, 7, buf_rle, huff_tree, &huffman_code);
+ }
+
+ StoreHuffmanTreeOfHuffmanTreeToBitMask(bw, code_length_bitdepth);
+ ClearHuffmanTreeIfOnlyOneSymbol(&huffman_code);
+ {
+ int trailing_zero_bits = 0;
+ int trimmed_length = num_tokens;
+ int write_trimmed_length;
+ int length;
+ int i = num_tokens;
+ while (i-- > 0) {
+ const int ix = tokens[i].code;
+ if (ix == 0 || ix == 17 || ix == 18) {
+ --trimmed_length; // discount trailing zeros
+ trailing_zero_bits += code_length_bitdepth[ix];
+ if (ix == 17) {
+ trailing_zero_bits += 3;
+ } else if (ix == 18) {
+ trailing_zero_bits += 7;
+ }
+ } else {
+ break;
+ }
+ }
+ write_trimmed_length = (trimmed_length > 1 && trailing_zero_bits > 12);
+ length = write_trimmed_length ? trimmed_length : num_tokens;
+ VP8LPutBits(bw, write_trimmed_length, 1);
+ if (write_trimmed_length) {
+ if (trimmed_length == 2) {
+ VP8LPutBits(bw, 0, 3 + 2); // nbitpairs=1, trimmed_length=2
+ } else {
+ const int nbits = BitsLog2Floor(trimmed_length - 2);
+ const int nbitpairs = nbits / 2 + 1;
+ assert(trimmed_length > 2);
+ assert(nbitpairs - 1 < 8);
+ VP8LPutBits(bw, nbitpairs - 1, 3);
+ VP8LPutBits(bw, trimmed_length - 2, nbitpairs * 2);
+ }
+ }
+ StoreHuffmanTreeToBitMask(bw, tokens, length, &huffman_code);
+ }
+}
+
+// 'huff_tree' and 'tokens' are pre-alloacted buffers.
+static void StoreHuffmanCode(VP8LBitWriter* const bw,
+ HuffmanTree* const huff_tree,
+ HuffmanTreeToken* const tokens,
+ const HuffmanTreeCode* const huffman_code) {
+ int i;
+ int count = 0;
+ int symbols[2] = { 0, 0 };
+ const int kMaxBits = 8;
+ const int kMaxSymbol = 1 << kMaxBits;
+
+ // Check whether it's a small tree.
+ for (i = 0; i < huffman_code->num_symbols && count < 3; ++i) {
+ if (huffman_code->code_lengths[i] != 0) {
+ if (count < 2) symbols[count] = i;
+ ++count;
+ }
+ }
+
+ if (count == 0) { // emit minimal tree for empty cases
+ // bits: small tree marker: 1, count-1: 0, large 8-bit code: 0, code: 0
+ VP8LPutBits(bw, 0x01, 4);
+ } else if (count <= 2 && symbols[0] < kMaxSymbol && symbols[1] < kMaxSymbol) {
+ VP8LPutBits(bw, 1, 1); // Small tree marker to encode 1 or 2 symbols.
+ VP8LPutBits(bw, count - 1, 1);
+ if (symbols[0] <= 1) {
+ VP8LPutBits(bw, 0, 1); // Code bit for small (1 bit) symbol value.
+ VP8LPutBits(bw, symbols[0], 1);
+ } else {
+ VP8LPutBits(bw, 1, 1);
+ VP8LPutBits(bw, symbols[0], 8);
+ }
+ if (count == 2) {
+ VP8LPutBits(bw, symbols[1], 8);
+ }
+ } else {
+ StoreFullHuffmanCode(bw, huff_tree, tokens, huffman_code);
+ }
+}
+
+static WEBP_INLINE void WriteHuffmanCode(VP8LBitWriter* const bw,
+ const HuffmanTreeCode* const code,
+ int code_index) {
+ const int depth = code->code_lengths[code_index];
+ const int symbol = code->codes[code_index];
+ VP8LPutBits(bw, symbol, depth);
+}
+
+static WEBP_INLINE void WriteHuffmanCodeWithExtraBits(
+ VP8LBitWriter* const bw,
+ const HuffmanTreeCode* const code,
+ int code_index,
+ int bits,
+ int n_bits) {
+ const int depth = code->code_lengths[code_index];
+ const int symbol = code->codes[code_index];
+ VP8LPutBits(bw, (bits << depth) | symbol, depth + n_bits);
+}
+
+static int StoreImageToBitMask(
+ VP8LBitWriter* const bw, int width, int histo_bits,
+ const VP8LBackwardRefs* const refs,
+ const uint16_t* histogram_symbols,
+ const HuffmanTreeCode* const huffman_codes, const WebPPicture* const pic) {
+ const int histo_xsize = histo_bits ? VP8LSubSampleSize(width, histo_bits) : 1;
+ const int tile_mask = (histo_bits == 0) ? 0 : -(1 << histo_bits);
+ // x and y trace the position in the image.
+ int x = 0;
+ int y = 0;
+ int tile_x = x & tile_mask;
+ int tile_y = y & tile_mask;
+ int histogram_ix = histogram_symbols[0];
+ const HuffmanTreeCode* codes = huffman_codes + 5 * histogram_ix;
+ VP8LRefsCursor c = VP8LRefsCursorInit(refs);
+ while (VP8LRefsCursorOk(&c)) {
+ const PixOrCopy* const v = c.cur_pos;
+ if ((tile_x != (x & tile_mask)) || (tile_y != (y & tile_mask))) {
+ tile_x = x & tile_mask;
+ tile_y = y & tile_mask;
+ histogram_ix = histogram_symbols[(y >> histo_bits) * histo_xsize +
+ (x >> histo_bits)];
+ codes = huffman_codes + 5 * histogram_ix;
+ }
+ if (PixOrCopyIsLiteral(v)) {
+ static const uint8_t order[] = { 1, 2, 0, 3 };
+ int k;
+ for (k = 0; k < 4; ++k) {
+ const int code = PixOrCopyLiteral(v, order[k]);
+ WriteHuffmanCode(bw, codes + k, code);
+ }
+ } else if (PixOrCopyIsCacheIdx(v)) {
+ const int code = PixOrCopyCacheIdx(v);
+ const int literal_ix = 256 + NUM_LENGTH_CODES + code;
+ WriteHuffmanCode(bw, codes, literal_ix);
+ } else {
+ int bits, n_bits;
+ int code;
+
+ const int distance = PixOrCopyDistance(v);
+ VP8LPrefixEncode(v->len, &code, &n_bits, &bits);
+ WriteHuffmanCodeWithExtraBits(bw, codes, 256 + code, bits, n_bits);
+
+ // Don't write the distance with the extra bits code since
+ // the distance can be up to 18 bits of extra bits, and the prefix
+ // 15 bits, totaling to 33, and our PutBits only supports up to 32 bits.
+ VP8LPrefixEncode(distance, &code, &n_bits, &bits);
+ WriteHuffmanCode(bw, codes + 4, code);
+ VP8LPutBits(bw, bits, n_bits);
+ }
+ x += PixOrCopyLength(v);
+ while (x >= width) {
+ x -= width;
+ ++y;
+ }
+ VP8LRefsCursorNext(&c);
+ }
+ if (bw->error_) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ return 1;
+}
+
+// Special case of EncodeImageInternal() for cache-bits=0, histo_bits=31.
+// pic and percent are for progress.
+static int EncodeImageNoHuffman(VP8LBitWriter* const bw,
+ const uint32_t* const argb,
+ VP8LHashChain* const hash_chain,
+ VP8LBackwardRefs* const refs_array, int width,
+ int height, int quality, int low_effort,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent) {
+ int i;
+ int max_tokens = 0;
+ VP8LBackwardRefs* refs;
+ HuffmanTreeToken* tokens = NULL;
+ HuffmanTreeCode huffman_codes[5] = {{0, NULL, NULL}};
+ const uint16_t histogram_symbols[1] = {0}; // only one tree, one symbol
+ int cache_bits = 0;
+ VP8LHistogramSet* histogram_image = NULL;
+ HuffmanTree* const huff_tree = (HuffmanTree*)WebPSafeMalloc(
+ 3ULL * CODE_LENGTH_CODES, sizeof(*huff_tree));
+ if (huff_tree == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // Calculate backward references from ARGB image.
+ if (!VP8LHashChainFill(hash_chain, quality, argb, width, height, low_effort,
+ pic, percent_range / 2, percent)) {
+ goto Error;
+ }
+ if (!VP8LGetBackwardReferences(width, height, argb, quality, /*low_effort=*/0,
+ kLZ77Standard | kLZ77RLE, cache_bits,
+ /*do_no_cache=*/0, hash_chain, refs_array,
+ &cache_bits, pic,
+ percent_range - percent_range / 2, percent)) {
+ goto Error;
+ }
+ refs = &refs_array[0];
+ histogram_image = VP8LAllocateHistogramSet(1, cache_bits);
+ if (histogram_image == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ VP8LHistogramSetClear(histogram_image);
+
+ // Build histogram image and symbols from backward references.
+ VP8LHistogramStoreRefs(refs, histogram_image->histograms[0]);
+
+ // Create Huffman bit lengths and codes for each histogram image.
+ assert(histogram_image->size == 1);
+ if (!GetHuffBitLengthsAndCodes(histogram_image, huffman_codes)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // No color cache, no Huffman image.
+ VP8LPutBits(bw, 0, 1);
+
+ // Find maximum number of symbols for the huffman tree-set.
+ for (i = 0; i < 5; ++i) {
+ HuffmanTreeCode* const codes = &huffman_codes[i];
+ if (max_tokens < codes->num_symbols) {
+ max_tokens = codes->num_symbols;
+ }
+ }
+
+ tokens = (HuffmanTreeToken*)WebPSafeMalloc(max_tokens, sizeof(*tokens));
+ if (tokens == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // Store Huffman codes.
+ for (i = 0; i < 5; ++i) {
+ HuffmanTreeCode* const codes = &huffman_codes[i];
+ StoreHuffmanCode(bw, huff_tree, tokens, codes);
+ ClearHuffmanTreeIfOnlyOneSymbol(codes);
+ }
+
+ // Store actual literals.
+ if (!StoreImageToBitMask(bw, width, 0, refs, histogram_symbols, huffman_codes,
+ pic)) {
+ goto Error;
+ }
+
+ Error:
+ WebPSafeFree(tokens);
+ WebPSafeFree(huff_tree);
+ VP8LFreeHistogramSet(histogram_image);
+ WebPSafeFree(huffman_codes[0].codes);
+ return (pic->error_code == VP8_ENC_OK);
+}
+
+// pic and percent are for progress.
+static int EncodeImageInternal(
+ VP8LBitWriter* const bw, const uint32_t* const argb,
+ VP8LHashChain* const hash_chain, VP8LBackwardRefs refs_array[4], int width,
+ int height, int quality, int low_effort, int use_cache,
+ const CrunchConfig* const config, int* cache_bits, int histogram_bits,
+ size_t init_byte_position, int* const hdr_size, int* const data_size,
+ const WebPPicture* const pic, int percent_range, int* const percent) {
+ const uint32_t histogram_image_xysize =
+ VP8LSubSampleSize(width, histogram_bits) *
+ VP8LSubSampleSize(height, histogram_bits);
+ int remaining_percent = percent_range;
+ int percent_start = *percent;
+ VP8LHistogramSet* histogram_image = NULL;
+ VP8LHistogram* tmp_histo = NULL;
+ int histogram_image_size = 0;
+ size_t bit_array_size = 0;
+ HuffmanTree* const huff_tree = (HuffmanTree*)WebPSafeMalloc(
+ 3ULL * CODE_LENGTH_CODES, sizeof(*huff_tree));
+ HuffmanTreeToken* tokens = NULL;
+ HuffmanTreeCode* huffman_codes = NULL;
+ uint16_t* const histogram_symbols = (uint16_t*)WebPSafeMalloc(
+ histogram_image_xysize, sizeof(*histogram_symbols));
+ int sub_configs_idx;
+ int cache_bits_init, write_histogram_image;
+ VP8LBitWriter bw_init = *bw, bw_best;
+ int hdr_size_tmp;
+ VP8LHashChain hash_chain_histogram; // histogram image hash chain
+ size_t bw_size_best = ~(size_t)0;
+ assert(histogram_bits >= MIN_HUFFMAN_BITS);
+ assert(histogram_bits <= MAX_HUFFMAN_BITS);
+ assert(hdr_size != NULL);
+ assert(data_size != NULL);
+
+ memset(&hash_chain_histogram, 0, sizeof(hash_chain_histogram));
+ if (!VP8LBitWriterInit(&bw_best, 0)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // Make sure we can allocate the different objects.
+ if (huff_tree == NULL || histogram_symbols == NULL ||
+ !VP8LHashChainInit(&hash_chain_histogram, histogram_image_xysize)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ percent_range = remaining_percent / 5;
+ if (!VP8LHashChainFill(hash_chain, quality, argb, width, height,
+ low_effort, pic, percent_range, percent)) {
+ goto Error;
+ }
+ percent_start += percent_range;
+ remaining_percent -= percent_range;
+
+ if (use_cache) {
+ // If the value is different from zero, it has been set during the
+ // palette analysis.
+ cache_bits_init = (*cache_bits == 0) ? MAX_COLOR_CACHE_BITS : *cache_bits;
+ } else {
+ cache_bits_init = 0;
+ }
+ // If several iterations will happen, clone into bw_best.
+ if ((config->sub_configs_size_ > 1 || config->sub_configs_[0].do_no_cache_) &&
+ !VP8LBitWriterClone(bw, &bw_best)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ for (sub_configs_idx = 0; sub_configs_idx < config->sub_configs_size_;
+ ++sub_configs_idx) {
+ const CrunchSubConfig* const sub_config =
+ &config->sub_configs_[sub_configs_idx];
+ int cache_bits_best, i_cache;
+ int i_remaining_percent = remaining_percent / config->sub_configs_size_;
+ int i_percent_range = i_remaining_percent / 4;
+ i_remaining_percent -= i_percent_range;
+
+ if (!VP8LGetBackwardReferences(
+ width, height, argb, quality, low_effort, sub_config->lz77_,
+ cache_bits_init, sub_config->do_no_cache_, hash_chain,
+ &refs_array[0], &cache_bits_best, pic, i_percent_range, percent)) {
+ goto Error;
+ }
+
+ for (i_cache = 0; i_cache < (sub_config->do_no_cache_ ? 2 : 1); ++i_cache) {
+ const int cache_bits_tmp = (i_cache == 0) ? cache_bits_best : 0;
+ // Speed-up: no need to study the no-cache case if it was already studied
+ // in i_cache == 0.
+ if (i_cache == 1 && cache_bits_best == 0) break;
+
+ // Reset the bit writer for this iteration.
+ VP8LBitWriterReset(&bw_init, bw);
+
+ // Build histogram image and symbols from backward references.
+ histogram_image =
+ VP8LAllocateHistogramSet(histogram_image_xysize, cache_bits_tmp);
+ tmp_histo = VP8LAllocateHistogram(cache_bits_tmp);
+ if (histogram_image == NULL || tmp_histo == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ i_percent_range = i_remaining_percent / 3;
+ i_remaining_percent -= i_percent_range;
+ if (!VP8LGetHistoImageSymbols(
+ width, height, &refs_array[i_cache], quality, low_effort,
+ histogram_bits, cache_bits_tmp, histogram_image, tmp_histo,
+ histogram_symbols, pic, i_percent_range, percent)) {
+ goto Error;
+ }
+ // Create Huffman bit lengths and codes for each histogram image.
+ histogram_image_size = histogram_image->size;
+ bit_array_size = 5 * histogram_image_size;
+ huffman_codes = (HuffmanTreeCode*)WebPSafeCalloc(bit_array_size,
+ sizeof(*huffman_codes));
+ // Note: some histogram_image entries may point to tmp_histos[], so the
+ // latter need to outlive the following call to
+ // GetHuffBitLengthsAndCodes().
+ if (huffman_codes == NULL ||
+ !GetHuffBitLengthsAndCodes(histogram_image, huffman_codes)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ // Free combined histograms.
+ VP8LFreeHistogramSet(histogram_image);
+ histogram_image = NULL;
+
+ // Free scratch histograms.
+ VP8LFreeHistogram(tmp_histo);
+ tmp_histo = NULL;
+
+ // Color Cache parameters.
+ if (cache_bits_tmp > 0) {
+ VP8LPutBits(bw, 1, 1);
+ VP8LPutBits(bw, cache_bits_tmp, 4);
+ } else {
+ VP8LPutBits(bw, 0, 1);
+ }
+
+ // Huffman image + meta huffman.
+ write_histogram_image = (histogram_image_size > 1);
+ VP8LPutBits(bw, write_histogram_image, 1);
+ if (write_histogram_image) {
+ uint32_t* const histogram_argb = (uint32_t*)WebPSafeMalloc(
+ histogram_image_xysize, sizeof(*histogram_argb));
+ int max_index = 0;
+ uint32_t i;
+ if (histogram_argb == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ for (i = 0; i < histogram_image_xysize; ++i) {
+ const int symbol_index = histogram_symbols[i] & 0xffff;
+ histogram_argb[i] = (symbol_index << 8);
+ if (symbol_index >= max_index) {
+ max_index = symbol_index + 1;
+ }
+ }
+ histogram_image_size = max_index;
+
+ VP8LPutBits(bw, histogram_bits - 2, 3);
+ i_percent_range = i_remaining_percent / 2;
+ i_remaining_percent -= i_percent_range;
+ if (!EncodeImageNoHuffman(
+ bw, histogram_argb, &hash_chain_histogram, &refs_array[2],
+ VP8LSubSampleSize(width, histogram_bits),
+ VP8LSubSampleSize(height, histogram_bits), quality, low_effort,
+ pic, i_percent_range, percent)) {
+ WebPSafeFree(histogram_argb);
+ goto Error;
+ }
+ WebPSafeFree(histogram_argb);
+ }
+
+ // Store Huffman codes.
+ {
+ int i;
+ int max_tokens = 0;
+ // Find maximum number of symbols for the huffman tree-set.
+ for (i = 0; i < 5 * histogram_image_size; ++i) {
+ HuffmanTreeCode* const codes = &huffman_codes[i];
+ if (max_tokens < codes->num_symbols) {
+ max_tokens = codes->num_symbols;
+ }
+ }
+ tokens = (HuffmanTreeToken*)WebPSafeMalloc(max_tokens, sizeof(*tokens));
+ if (tokens == NULL) goto Error;
+ for (i = 0; i < 5 * histogram_image_size; ++i) {
+ HuffmanTreeCode* const codes = &huffman_codes[i];
+ StoreHuffmanCode(bw, huff_tree, tokens, codes);
+ ClearHuffmanTreeIfOnlyOneSymbol(codes);
+ }
+ }
+ // Store actual literals.
+ hdr_size_tmp = (int)(VP8LBitWriterNumBytes(bw) - init_byte_position);
+ if (!StoreImageToBitMask(bw, width, histogram_bits, &refs_array[i_cache],
+ histogram_symbols, huffman_codes, pic)) {
+ goto Error;
+ }
+ // Keep track of the smallest image so far.
+ if (VP8LBitWriterNumBytes(bw) < bw_size_best) {
+ bw_size_best = VP8LBitWriterNumBytes(bw);
+ *cache_bits = cache_bits_tmp;
+ *hdr_size = hdr_size_tmp;
+ *data_size =
+ (int)(VP8LBitWriterNumBytes(bw) - init_byte_position - *hdr_size);
+ VP8LBitWriterSwap(bw, &bw_best);
+ }
+ WebPSafeFree(tokens);
+ tokens = NULL;
+ if (huffman_codes != NULL) {
+ WebPSafeFree(huffman_codes->codes);
+ WebPSafeFree(huffman_codes);
+ huffman_codes = NULL;
+ }
+ }
+ }
+ VP8LBitWriterSwap(bw, &bw_best);
+
+ if (!WebPReportProgress(pic, percent_start + remaining_percent, percent)) {
+ goto Error;
+ }
+
+ Error:
+ WebPSafeFree(tokens);
+ WebPSafeFree(huff_tree);
+ VP8LFreeHistogramSet(histogram_image);
+ VP8LFreeHistogram(tmp_histo);
+ VP8LHashChainClear(&hash_chain_histogram);
+ if (huffman_codes != NULL) {
+ WebPSafeFree(huffman_codes->codes);
+ WebPSafeFree(huffman_codes);
+ }
+ WebPSafeFree(histogram_symbols);
+ VP8LBitWriterWipeOut(&bw_best);
+ return (pic->error_code == VP8_ENC_OK);
+}
+
+// -----------------------------------------------------------------------------
+// Transforms
+
+static void ApplySubtractGreen(VP8LEncoder* const enc, int width, int height,
+ VP8LBitWriter* const bw) {
+ VP8LPutBits(bw, TRANSFORM_PRESENT, 1);
+ VP8LPutBits(bw, SUBTRACT_GREEN_TRANSFORM, 2);
+ VP8LSubtractGreenFromBlueAndRed(enc->argb_, width * height);
+}
+
+static int ApplyPredictFilter(const VP8LEncoder* const enc, int width,
+ int height, int quality, int low_effort,
+ int used_subtract_green, VP8LBitWriter* const bw,
+ int percent_range, int* const percent) {
+ const int pred_bits = enc->transform_bits_;
+ const int transform_width = VP8LSubSampleSize(width, pred_bits);
+ const int transform_height = VP8LSubSampleSize(height, pred_bits);
+ // we disable near-lossless quantization if palette is used.
+ const int near_lossless_strength =
+ enc->use_palette_ ? 100 : enc->config_->near_lossless;
+
+ if (!VP8LResidualImage(
+ width, height, pred_bits, low_effort, enc->argb_, enc->argb_scratch_,
+ enc->transform_data_, near_lossless_strength, enc->config_->exact,
+ used_subtract_green, enc->pic_, percent_range / 2, percent)) {
+ return 0;
+ }
+ VP8LPutBits(bw, TRANSFORM_PRESENT, 1);
+ VP8LPutBits(bw, PREDICTOR_TRANSFORM, 2);
+ assert(pred_bits >= 2);
+ VP8LPutBits(bw, pred_bits - 2, 3);
+ return EncodeImageNoHuffman(
+ bw, enc->transform_data_, (VP8LHashChain*)&enc->hash_chain_,
+ (VP8LBackwardRefs*)&enc->refs_[0], transform_width, transform_height,
+ quality, low_effort, enc->pic_, percent_range - percent_range / 2,
+ percent);
+}
+
+static int ApplyCrossColorFilter(const VP8LEncoder* const enc, int width,
+ int height, int quality, int low_effort,
+ VP8LBitWriter* const bw, int percent_range,
+ int* const percent) {
+ const int ccolor_transform_bits = enc->transform_bits_;
+ const int transform_width = VP8LSubSampleSize(width, ccolor_transform_bits);
+ const int transform_height = VP8LSubSampleSize(height, ccolor_transform_bits);
+
+ if (!VP8LColorSpaceTransform(width, height, ccolor_transform_bits, quality,
+ enc->argb_, enc->transform_data_, enc->pic_,
+ percent_range / 2, percent)) {
+ return 0;
+ }
+ VP8LPutBits(bw, TRANSFORM_PRESENT, 1);
+ VP8LPutBits(bw, CROSS_COLOR_TRANSFORM, 2);
+ assert(ccolor_transform_bits >= 2);
+ VP8LPutBits(bw, ccolor_transform_bits - 2, 3);
+ return EncodeImageNoHuffman(
+ bw, enc->transform_data_, (VP8LHashChain*)&enc->hash_chain_,
+ (VP8LBackwardRefs*)&enc->refs_[0], transform_width, transform_height,
+ quality, low_effort, enc->pic_, percent_range - percent_range / 2,
+ percent);
+}
+
+// -----------------------------------------------------------------------------
+
+static int WriteRiffHeader(const WebPPicture* const pic, size_t riff_size,
+ size_t vp8l_size) {
+ uint8_t riff[RIFF_HEADER_SIZE + CHUNK_HEADER_SIZE + VP8L_SIGNATURE_SIZE] = {
+ 'R', 'I', 'F', 'F', 0, 0, 0, 0, 'W', 'E', 'B', 'P',
+ 'V', 'P', '8', 'L', 0, 0, 0, 0, VP8L_MAGIC_BYTE,
+ };
+ PutLE32(riff + TAG_SIZE, (uint32_t)riff_size);
+ PutLE32(riff + RIFF_HEADER_SIZE + TAG_SIZE, (uint32_t)vp8l_size);
+ return pic->writer(riff, sizeof(riff), pic);
+}
+
+static int WriteImageSize(const WebPPicture* const pic,
+ VP8LBitWriter* const bw) {
+ const int width = pic->width - 1;
+ const int height = pic->height - 1;
+ assert(width < WEBP_MAX_DIMENSION && height < WEBP_MAX_DIMENSION);
+
+ VP8LPutBits(bw, width, VP8L_IMAGE_SIZE_BITS);
+ VP8LPutBits(bw, height, VP8L_IMAGE_SIZE_BITS);
+ return !bw->error_;
+}
+
+static int WriteRealAlphaAndVersion(VP8LBitWriter* const bw, int has_alpha) {
+ VP8LPutBits(bw, has_alpha, 1);
+ VP8LPutBits(bw, VP8L_VERSION, VP8L_VERSION_BITS);
+ return !bw->error_;
+}
+
+static int WriteImage(const WebPPicture* const pic, VP8LBitWriter* const bw,
+ size_t* const coded_size) {
+ const uint8_t* const webpll_data = VP8LBitWriterFinish(bw);
+ const size_t webpll_size = VP8LBitWriterNumBytes(bw);
+ const size_t vp8l_size = VP8L_SIGNATURE_SIZE + webpll_size;
+ const size_t pad = vp8l_size & 1;
+ const size_t riff_size = TAG_SIZE + CHUNK_HEADER_SIZE + vp8l_size + pad;
+
+ if (!WriteRiffHeader(pic, riff_size, vp8l_size) ||
+ !pic->writer(webpll_data, webpll_size, pic)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_WRITE);
+ return 0;
+ }
+
+ if (pad) {
+ const uint8_t pad_byte[1] = { 0 };
+ if (!pic->writer(pad_byte, 1, pic)) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_WRITE);
+ return 0;
+ }
+ }
+ *coded_size = CHUNK_HEADER_SIZE + riff_size;
+ return 1;
+}
+
+// -----------------------------------------------------------------------------
+
+static void ClearTransformBuffer(VP8LEncoder* const enc) {
+ WebPSafeFree(enc->transform_mem_);
+ enc->transform_mem_ = NULL;
+ enc->transform_mem_size_ = 0;
+}
+
+// Allocates the memory for argb (W x H) buffer, 2 rows of context for
+// prediction and transform data.
+// Flags influencing the memory allocated:
+// enc->transform_bits_
+// enc->use_predict_, enc->use_cross_color_
+static int AllocateTransformBuffer(VP8LEncoder* const enc, int width,
+ int height) {
+ const uint64_t image_size = width * height;
+ // VP8LResidualImage needs room for 2 scanlines of uint32 pixels with an extra
+ // pixel in each, plus 2 regular scanlines of bytes.
+ // TODO(skal): Clean up by using arithmetic in bytes instead of words.
+ const uint64_t argb_scratch_size =
+ enc->use_predict_ ? (width + 1) * 2 + (width * 2 + sizeof(uint32_t) - 1) /
+ sizeof(uint32_t)
+ : 0;
+ const uint64_t transform_data_size =
+ (enc->use_predict_ || enc->use_cross_color_)
+ ? VP8LSubSampleSize(width, enc->transform_bits_) *
+ VP8LSubSampleSize(height, enc->transform_bits_)
+ : 0;
+ const uint64_t max_alignment_in_words =
+ (WEBP_ALIGN_CST + sizeof(uint32_t) - 1) / sizeof(uint32_t);
+ const uint64_t mem_size = image_size + max_alignment_in_words +
+ argb_scratch_size + max_alignment_in_words +
+ transform_data_size;
+ uint32_t* mem = enc->transform_mem_;
+ if (mem == NULL || mem_size > enc->transform_mem_size_) {
+ ClearTransformBuffer(enc);
+ mem = (uint32_t*)WebPSafeMalloc(mem_size, sizeof(*mem));
+ if (mem == NULL) {
+ WebPEncodingSetError(enc->pic_, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+ enc->transform_mem_ = mem;
+ enc->transform_mem_size_ = (size_t)mem_size;
+ enc->argb_content_ = kEncoderNone;
+ }
+ enc->argb_ = mem;
+ mem = (uint32_t*)WEBP_ALIGN(mem + image_size);
+ enc->argb_scratch_ = mem;
+ mem = (uint32_t*)WEBP_ALIGN(mem + argb_scratch_size);
+ enc->transform_data_ = mem;
+
+ enc->current_width_ = width;
+ return 1;
+}
+
+static int MakeInputImageCopy(VP8LEncoder* const enc) {
+ const WebPPicture* const picture = enc->pic_;
+ const int width = picture->width;
+ const int height = picture->height;
+
+ if (!AllocateTransformBuffer(enc, width, height)) return 0;
+ if (enc->argb_content_ == kEncoderARGB) return 1;
+
+ {
+ uint32_t* dst = enc->argb_;
+ const uint32_t* src = picture->argb;
+ int y;
+ for (y = 0; y < height; ++y) {
+ memcpy(dst, src, width * sizeof(*dst));
+ dst += width;
+ src += picture->argb_stride;
+ }
+ }
+ enc->argb_content_ = kEncoderARGB;
+ assert(enc->current_width_ == width);
+ return 1;
+}
+
+// -----------------------------------------------------------------------------
+
+#define APPLY_PALETTE_GREEDY_MAX 4
+
+static WEBP_INLINE uint32_t SearchColorGreedy(const uint32_t palette[],
+ int palette_size,
+ uint32_t color) {
+ (void)palette_size;
+ assert(palette_size < APPLY_PALETTE_GREEDY_MAX);
+ assert(3 == APPLY_PALETTE_GREEDY_MAX - 1);
+ if (color == palette[0]) return 0;
+ if (color == palette[1]) return 1;
+ if (color == palette[2]) return 2;
+ return 3;
+}
+
+static WEBP_INLINE uint32_t ApplyPaletteHash0(uint32_t color) {
+ // Focus on the green color.
+ return (color >> 8) & 0xff;
+}
+
+#define PALETTE_INV_SIZE_BITS 11
+#define PALETTE_INV_SIZE (1 << PALETTE_INV_SIZE_BITS)
+
+static WEBP_INLINE uint32_t ApplyPaletteHash1(uint32_t color) {
+ // Forget about alpha.
+ return ((uint32_t)((color & 0x00ffffffu) * 4222244071ull)) >>
+ (32 - PALETTE_INV_SIZE_BITS);
+}
+
+static WEBP_INLINE uint32_t ApplyPaletteHash2(uint32_t color) {
+ // Forget about alpha.
+ return ((uint32_t)((color & 0x00ffffffu) * ((1ull << 31) - 1))) >>
+ (32 - PALETTE_INV_SIZE_BITS);
+}
+
+// Use 1 pixel cache for ARGB pixels.
+#define APPLY_PALETTE_FOR(COLOR_INDEX) do { \
+ uint32_t prev_pix = palette[0]; \
+ uint32_t prev_idx = 0; \
+ for (y = 0; y < height; ++y) { \
+ for (x = 0; x < width; ++x) { \
+ const uint32_t pix = src[x]; \
+ if (pix != prev_pix) { \
+ prev_idx = COLOR_INDEX; \
+ prev_pix = pix; \
+ } \
+ tmp_row[x] = prev_idx; \
+ } \
+ VP8LBundleColorMap(tmp_row, width, xbits, dst); \
+ src += src_stride; \
+ dst += dst_stride; \
+ } \
+} while (0)
+
+// Remap argb values in src[] to packed palettes entries in dst[]
+// using 'row' as a temporary buffer of size 'width'.
+// We assume that all src[] values have a corresponding entry in the palette.
+// Note: src[] can be the same as dst[]
+static int ApplyPalette(const uint32_t* src, uint32_t src_stride, uint32_t* dst,
+ uint32_t dst_stride, const uint32_t* palette,
+ int palette_size, int width, int height, int xbits,
+ const WebPPicture* const pic) {
+ // TODO(skal): this tmp buffer is not needed if VP8LBundleColorMap() can be
+ // made to work in-place.
+ uint8_t* const tmp_row = (uint8_t*)WebPSafeMalloc(width, sizeof(*tmp_row));
+ int x, y;
+
+ if (tmp_row == NULL) {
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return 0;
+ }
+
+ if (palette_size < APPLY_PALETTE_GREEDY_MAX) {
+ APPLY_PALETTE_FOR(SearchColorGreedy(palette, palette_size, pix));
+ } else {
+ int i, j;
+ uint16_t buffer[PALETTE_INV_SIZE];
+ uint32_t (*const hash_functions[])(uint32_t) = {
+ ApplyPaletteHash0, ApplyPaletteHash1, ApplyPaletteHash2
+ };
+
+ // Try to find a perfect hash function able to go from a color to an index
+ // within 1 << PALETTE_INV_SIZE_BITS in order to build a hash map to go
+ // from color to index in palette.
+ for (i = 0; i < 3; ++i) {
+ int use_LUT = 1;
+ // Set each element in buffer to max uint16_t.
+ memset(buffer, 0xff, sizeof(buffer));
+ for (j = 0; j < palette_size; ++j) {
+ const uint32_t ind = hash_functions[i](palette[j]);
+ if (buffer[ind] != 0xffffu) {
+ use_LUT = 0;
+ break;
+ } else {
+ buffer[ind] = j;
+ }
+ }
+ if (use_LUT) break;
+ }
+
+ if (i == 0) {
+ APPLY_PALETTE_FOR(buffer[ApplyPaletteHash0(pix)]);
+ } else if (i == 1) {
+ APPLY_PALETTE_FOR(buffer[ApplyPaletteHash1(pix)]);
+ } else if (i == 2) {
+ APPLY_PALETTE_FOR(buffer[ApplyPaletteHash2(pix)]);
+ } else {
+ uint32_t idx_map[MAX_PALETTE_SIZE];
+ uint32_t palette_sorted[MAX_PALETTE_SIZE];
+ PrepareMapToPalette(palette, palette_size, palette_sorted, idx_map);
+ APPLY_PALETTE_FOR(
+ idx_map[SearchColorNoIdx(palette_sorted, pix, palette_size)]);
+ }
+ }
+ WebPSafeFree(tmp_row);
+ return 1;
+}
+#undef APPLY_PALETTE_FOR
+#undef PALETTE_INV_SIZE_BITS
+#undef PALETTE_INV_SIZE
+#undef APPLY_PALETTE_GREEDY_MAX
+
+// Note: Expects "enc->palette_" to be set properly.
+static int MapImageFromPalette(VP8LEncoder* const enc, int in_place) {
+ const WebPPicture* const pic = enc->pic_;
+ const int width = pic->width;
+ const int height = pic->height;
+ const uint32_t* const palette = enc->palette_;
+ const uint32_t* src = in_place ? enc->argb_ : pic->argb;
+ const int src_stride = in_place ? enc->current_width_ : pic->argb_stride;
+ const int palette_size = enc->palette_size_;
+ int xbits;
+
+ // Replace each input pixel by corresponding palette index.
+ // This is done line by line.
+ if (palette_size <= 4) {
+ xbits = (palette_size <= 2) ? 3 : 2;
+ } else {
+ xbits = (palette_size <= 16) ? 1 : 0;
+ }
+
+ if (!AllocateTransformBuffer(enc, VP8LSubSampleSize(width, xbits), height)) {
+ return 0;
+ }
+ if (!ApplyPalette(src, src_stride,
+ enc->argb_, enc->current_width_,
+ palette, palette_size, width, height, xbits, pic)) {
+ return 0;
+ }
+ enc->argb_content_ = kEncoderPalette;
+ return 1;
+}
+
+// Save palette_[] to bitstream.
+static WebPEncodingError EncodePalette(VP8LBitWriter* const bw, int low_effort,
+ VP8LEncoder* const enc,
+ int percent_range, int* const percent) {
+ int i;
+ uint32_t tmp_palette[MAX_PALETTE_SIZE];
+ const int palette_size = enc->palette_size_;
+ const uint32_t* const palette = enc->palette_;
+ VP8LPutBits(bw, TRANSFORM_PRESENT, 1);
+ VP8LPutBits(bw, COLOR_INDEXING_TRANSFORM, 2);
+ assert(palette_size >= 1 && palette_size <= MAX_PALETTE_SIZE);
+ VP8LPutBits(bw, palette_size - 1, 8);
+ for (i = palette_size - 1; i >= 1; --i) {
+ tmp_palette[i] = VP8LSubPixels(palette[i], palette[i - 1]);
+ }
+ tmp_palette[0] = palette[0];
+ return EncodeImageNoHuffman(bw, tmp_palette, &enc->hash_chain_,
+ &enc->refs_[0], palette_size, 1, /*quality=*/20,
+ low_effort, enc->pic_, percent_range, percent);
+}
+
+// -----------------------------------------------------------------------------
+// VP8LEncoder
+
+static VP8LEncoder* VP8LEncoderNew(const WebPConfig* const config,
+ const WebPPicture* const picture) {
+ VP8LEncoder* const enc = (VP8LEncoder*)WebPSafeCalloc(1ULL, sizeof(*enc));
+ if (enc == NULL) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return NULL;
+ }
+ enc->config_ = config;
+ enc->pic_ = picture;
+ enc->argb_content_ = kEncoderNone;
+
+ VP8LEncDspInit();
+
+ return enc;
+}
+
+static void VP8LEncoderDelete(VP8LEncoder* enc) {
+ if (enc != NULL) {
+ int i;
+ VP8LHashChainClear(&enc->hash_chain_);
+ for (i = 0; i < 4; ++i) VP8LBackwardRefsClear(&enc->refs_[i]);
+ ClearTransformBuffer(enc);
+ WebPSafeFree(enc);
+ }
+}
+
+// -----------------------------------------------------------------------------
+// Main call
+
+typedef struct {
+ const WebPConfig* config_;
+ const WebPPicture* picture_;
+ VP8LBitWriter* bw_;
+ VP8LEncoder* enc_;
+ int use_cache_;
+ CrunchConfig crunch_configs_[CRUNCH_CONFIGS_MAX];
+ int num_crunch_configs_;
+ int red_and_blue_always_zero_;
+ WebPAuxStats* stats_;
+} StreamEncodeContext;
+
+static int EncodeStreamHook(void* input, void* data2) {
+ StreamEncodeContext* const params = (StreamEncodeContext*)input;
+ const WebPConfig* const config = params->config_;
+ const WebPPicture* const picture = params->picture_;
+ VP8LBitWriter* const bw = params->bw_;
+ VP8LEncoder* const enc = params->enc_;
+ const int use_cache = params->use_cache_;
+ const CrunchConfig* const crunch_configs = params->crunch_configs_;
+ const int num_crunch_configs = params->num_crunch_configs_;
+ const int red_and_blue_always_zero = params->red_and_blue_always_zero_;
+#if !defined(WEBP_DISABLE_STATS)
+ WebPAuxStats* const stats = params->stats_;
+#endif
+ const int quality = (int)config->quality;
+ const int low_effort = (config->method == 0);
+#if (WEBP_NEAR_LOSSLESS == 1)
+ const int width = picture->width;
+#endif
+ const int height = picture->height;
+ const size_t byte_position = VP8LBitWriterNumBytes(bw);
+ int percent = 2; // for WebPProgressHook
+#if (WEBP_NEAR_LOSSLESS == 1)
+ int use_near_lossless = 0;
+#endif
+ int hdr_size = 0;
+ int data_size = 0;
+ int use_delta_palette = 0;
+ int idx;
+ size_t best_size = ~(size_t)0;
+ VP8LBitWriter bw_init = *bw, bw_best;
+ (void)data2;
+
+ if (!VP8LBitWriterInit(&bw_best, 0) ||
+ (num_crunch_configs > 1 && !VP8LBitWriterClone(bw, &bw_best))) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ for (idx = 0; idx < num_crunch_configs; ++idx) {
+ const int entropy_idx = crunch_configs[idx].entropy_idx_;
+ int remaining_percent = 97 / num_crunch_configs, percent_range;
+ enc->use_palette_ =
+ (entropy_idx == kPalette) || (entropy_idx == kPaletteAndSpatial);
+ enc->use_subtract_green_ =
+ (entropy_idx == kSubGreen) || (entropy_idx == kSpatialSubGreen);
+ enc->use_predict_ = (entropy_idx == kSpatial) ||
+ (entropy_idx == kSpatialSubGreen) ||
+ (entropy_idx == kPaletteAndSpatial);
+ // When using a palette, R/B==0, hence no need to test for cross-color.
+ if (low_effort || enc->use_palette_) {
+ enc->use_cross_color_ = 0;
+ } else {
+ enc->use_cross_color_ = red_and_blue_always_zero ? 0 : enc->use_predict_;
+ }
+ // Reset any parameter in the encoder that is set in the previous iteration.
+ enc->cache_bits_ = 0;
+ VP8LBackwardRefsClear(&enc->refs_[0]);
+ VP8LBackwardRefsClear(&enc->refs_[1]);
+
+#if (WEBP_NEAR_LOSSLESS == 1)
+ // Apply near-lossless preprocessing.
+ use_near_lossless = (config->near_lossless < 100) && !enc->use_palette_ &&
+ !enc->use_predict_;
+ if (use_near_lossless) {
+ if (!AllocateTransformBuffer(enc, width, height)) goto Error;
+ if ((enc->argb_content_ != kEncoderNearLossless) &&
+ !VP8ApplyNearLossless(picture, config->near_lossless, enc->argb_)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ enc->argb_content_ = kEncoderNearLossless;
+ } else {
+ enc->argb_content_ = kEncoderNone;
+ }
+#else
+ enc->argb_content_ = kEncoderNone;
+#endif
+
+ // Encode palette
+ if (enc->use_palette_) {
+ if (crunch_configs[idx].palette_sorting_type_ == kSortedDefault) {
+ // Nothing to do, we have already sorted the palette.
+ memcpy(enc->palette_, enc->palette_sorted_,
+ enc->palette_size_ * sizeof(*enc->palette_));
+ } else if (crunch_configs[idx].palette_sorting_type_ == kMinimizeDelta) {
+ PaletteSortMinimizeDeltas(enc->palette_sorted_, enc->palette_size_,
+ enc->palette_);
+ } else {
+ assert(crunch_configs[idx].palette_sorting_type_ == kModifiedZeng);
+ if (!PaletteSortModifiedZeng(enc->pic_, enc->palette_sorted_,
+ enc->palette_size_, enc->palette_)) {
+ goto Error;
+ }
+ }
+ percent_range = remaining_percent / 4;
+ if (!EncodePalette(bw, low_effort, enc, percent_range, &percent)) {
+ goto Error;
+ }
+ remaining_percent -= percent_range;
+ if (!MapImageFromPalette(enc, use_delta_palette)) goto Error;
+ // If using a color cache, do not have it bigger than the number of
+ // colors.
+ if (use_cache && enc->palette_size_ < (1 << MAX_COLOR_CACHE_BITS)) {
+ enc->cache_bits_ = BitsLog2Floor(enc->palette_size_) + 1;
+ }
+ }
+ if (!use_delta_palette) {
+ // In case image is not packed.
+ if (enc->argb_content_ != kEncoderNearLossless &&
+ enc->argb_content_ != kEncoderPalette) {
+ if (!MakeInputImageCopy(enc)) goto Error;
+ }
+
+ // -----------------------------------------------------------------------
+ // Apply transforms and write transform data.
+
+ if (enc->use_subtract_green_) {
+ ApplySubtractGreen(enc, enc->current_width_, height, bw);
+ }
+
+ if (enc->use_predict_) {
+ percent_range = remaining_percent / 3;
+ if (!ApplyPredictFilter(enc, enc->current_width_, height, quality,
+ low_effort, enc->use_subtract_green_, bw,
+ percent_range, &percent)) {
+ goto Error;
+ }
+ remaining_percent -= percent_range;
+ }
+
+ if (enc->use_cross_color_) {
+ percent_range = remaining_percent / 2;
+ if (!ApplyCrossColorFilter(enc, enc->current_width_, height, quality,
+ low_effort, bw, percent_range, &percent)) {
+ goto Error;
+ }
+ remaining_percent -= percent_range;
+ }
+ }
+
+ VP8LPutBits(bw, !TRANSFORM_PRESENT, 1); // No more transforms.
+
+ // -------------------------------------------------------------------------
+ // Encode and write the transformed image.
+ if (!EncodeImageInternal(
+ bw, enc->argb_, &enc->hash_chain_, enc->refs_, enc->current_width_,
+ height, quality, low_effort, use_cache, &crunch_configs[idx],
+ &enc->cache_bits_, enc->histo_bits_, byte_position, &hdr_size,
+ &data_size, picture, remaining_percent, &percent)) {
+ goto Error;
+ }
+
+ // If we are better than what we already have.
+ if (VP8LBitWriterNumBytes(bw) < best_size) {
+ best_size = VP8LBitWriterNumBytes(bw);
+ // Store the BitWriter.
+ VP8LBitWriterSwap(bw, &bw_best);
+#if !defined(WEBP_DISABLE_STATS)
+ // Update the stats.
+ if (stats != NULL) {
+ stats->lossless_features = 0;
+ if (enc->use_predict_) stats->lossless_features |= 1;
+ if (enc->use_cross_color_) stats->lossless_features |= 2;
+ if (enc->use_subtract_green_) stats->lossless_features |= 4;
+ if (enc->use_palette_) stats->lossless_features |= 8;
+ stats->histogram_bits = enc->histo_bits_;
+ stats->transform_bits = enc->transform_bits_;
+ stats->cache_bits = enc->cache_bits_;
+ stats->palette_size = enc->palette_size_;
+ stats->lossless_size = (int)(best_size - byte_position);
+ stats->lossless_hdr_size = hdr_size;
+ stats->lossless_data_size = data_size;
+ }
+#endif
+ }
+ // Reset the bit writer for the following iteration if any.
+ if (num_crunch_configs > 1) VP8LBitWriterReset(&bw_init, bw);
+ }
+ VP8LBitWriterSwap(&bw_best, bw);
+
+ Error:
+ VP8LBitWriterWipeOut(&bw_best);
+ // The hook should return false in case of error.
+ return (params->picture_->error_code == VP8_ENC_OK);
+}
+
+int VP8LEncodeStream(const WebPConfig* const config,
+ const WebPPicture* const picture,
+ VP8LBitWriter* const bw_main, int use_cache) {
+ VP8LEncoder* const enc_main = VP8LEncoderNew(config, picture);
+ VP8LEncoder* enc_side = NULL;
+ CrunchConfig crunch_configs[CRUNCH_CONFIGS_MAX];
+ int num_crunch_configs_main, num_crunch_configs_side = 0;
+ int idx;
+ int red_and_blue_always_zero = 0;
+ WebPWorker worker_main, worker_side;
+ StreamEncodeContext params_main, params_side;
+ // The main thread uses picture->stats, the side thread uses stats_side.
+ WebPAuxStats stats_side;
+ VP8LBitWriter bw_side;
+ WebPPicture picture_side;
+ const WebPWorkerInterface* const worker_interface = WebPGetWorkerInterface();
+ int ok_main;
+
+ if (enc_main == NULL || !VP8LBitWriterInit(&bw_side, 0)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ VP8LEncoderDelete(enc_main);
+ return 0;
+ }
+
+ // Avoid "garbage value" error from Clang's static analysis tool.
+ WebPPictureInit(&picture_side);
+
+ // Analyze image (entropy, num_palettes etc)
+ if (!EncoderAnalyze(enc_main, crunch_configs, &num_crunch_configs_main,
+ &red_and_blue_always_zero) ||
+ !EncoderInit(enc_main)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ // Split the configs between the main and side threads (if any).
+ if (config->thread_level > 0) {
+ num_crunch_configs_side = num_crunch_configs_main / 2;
+ for (idx = 0; idx < num_crunch_configs_side; ++idx) {
+ params_side.crunch_configs_[idx] =
+ crunch_configs[num_crunch_configs_main - num_crunch_configs_side +
+ idx];
+ }
+ params_side.num_crunch_configs_ = num_crunch_configs_side;
+ }
+ num_crunch_configs_main -= num_crunch_configs_side;
+ for (idx = 0; idx < num_crunch_configs_main; ++idx) {
+ params_main.crunch_configs_[idx] = crunch_configs[idx];
+ }
+ params_main.num_crunch_configs_ = num_crunch_configs_main;
+
+ // Fill in the parameters for the thread workers.
+ {
+ const int params_size = (num_crunch_configs_side > 0) ? 2 : 1;
+ for (idx = 0; idx < params_size; ++idx) {
+ // Create the parameters for each worker.
+ WebPWorker* const worker = (idx == 0) ? &worker_main : &worker_side;
+ StreamEncodeContext* const param =
+ (idx == 0) ? &params_main : &params_side;
+ param->config_ = config;
+ param->use_cache_ = use_cache;
+ param->red_and_blue_always_zero_ = red_and_blue_always_zero;
+ if (idx == 0) {
+ param->picture_ = picture;
+ param->stats_ = picture->stats;
+ param->bw_ = bw_main;
+ param->enc_ = enc_main;
+ } else {
+ // Create a side picture (error_code is not thread-safe).
+ if (!WebPPictureView(picture, /*left=*/0, /*top=*/0, picture->width,
+ picture->height, &picture_side)) {
+ assert(0);
+ }
+ picture_side.progress_hook = NULL; // Progress hook is not thread-safe.
+ param->picture_ = &picture_side; // No need to free a view afterwards.
+ param->stats_ = (picture->stats == NULL) ? NULL : &stats_side;
+ // Create a side bit writer.
+ if (!VP8LBitWriterClone(bw_main, &bw_side)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ param->bw_ = &bw_side;
+ // Create a side encoder.
+ enc_side = VP8LEncoderNew(config, &picture_side);
+ if (enc_side == NULL || !EncoderInit(enc_side)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+ // Copy the values that were computed for the main encoder.
+ enc_side->histo_bits_ = enc_main->histo_bits_;
+ enc_side->transform_bits_ = enc_main->transform_bits_;
+ enc_side->palette_size_ = enc_main->palette_size_;
+ memcpy(enc_side->palette_, enc_main->palette_,
+ sizeof(enc_main->palette_));
+ memcpy(enc_side->palette_sorted_, enc_main->palette_sorted_,
+ sizeof(enc_main->palette_sorted_));
+ param->enc_ = enc_side;
+ }
+ // Create the workers.
+ worker_interface->Init(worker);
+ worker->data1 = param;
+ worker->data2 = NULL;
+ worker->hook = EncodeStreamHook;
+ }
+ }
+
+ // Start the second thread if needed.
+ if (num_crunch_configs_side != 0) {
+ if (!worker_interface->Reset(&worker_side)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+#if !defined(WEBP_DISABLE_STATS)
+ // This line is here and not in the param initialization above to remove a
+ // Clang static analyzer warning.
+ if (picture->stats != NULL) {
+ memcpy(&stats_side, picture->stats, sizeof(stats_side));
+ }
+#endif
+ worker_interface->Launch(&worker_side);
+ }
+ // Execute the main thread.
+ worker_interface->Execute(&worker_main);
+ ok_main = worker_interface->Sync(&worker_main);
+ worker_interface->End(&worker_main);
+ if (num_crunch_configs_side != 0) {
+ // Wait for the second thread.
+ const int ok_side = worker_interface->Sync(&worker_side);
+ worker_interface->End(&worker_side);
+ if (!ok_main || !ok_side) {
+ if (picture->error_code == VP8_ENC_OK) {
+ assert(picture_side.error_code != VP8_ENC_OK);
+ WebPEncodingSetError(picture, picture_side.error_code);
+ }
+ goto Error;
+ }
+ if (VP8LBitWriterNumBytes(&bw_side) < VP8LBitWriterNumBytes(bw_main)) {
+ VP8LBitWriterSwap(bw_main, &bw_side);
+#if !defined(WEBP_DISABLE_STATS)
+ if (picture->stats != NULL) {
+ memcpy(picture->stats, &stats_side, sizeof(*picture->stats));
+ }
+#endif
+ }
+ }
+
+ Error:
+ VP8LBitWriterWipeOut(&bw_side);
+ VP8LEncoderDelete(enc_main);
+ VP8LEncoderDelete(enc_side);
+ return (picture->error_code == VP8_ENC_OK);
+}
+
+#undef CRUNCH_CONFIGS_MAX
+#undef CRUNCH_SUBCONFIGS_MAX
+
+int VP8LEncodeImage(const WebPConfig* const config,
+ const WebPPicture* const picture) {
+ int width, height;
+ int has_alpha;
+ size_t coded_size;
+ int percent = 0;
+ int initial_size;
+ VP8LBitWriter bw;
+
+ if (picture == NULL) return 0;
+
+ if (config == NULL || picture->argb == NULL) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER);
+ return 0;
+ }
+
+ width = picture->width;
+ height = picture->height;
+ // Initialize BitWriter with size corresponding to 16 bpp to photo images and
+ // 8 bpp for graphical images.
+ initial_size = (config->image_hint == WEBP_HINT_GRAPH) ?
+ width * height : width * height * 2;
+ if (!VP8LBitWriterInit(&bw, initial_size)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ if (!WebPReportProgress(picture, 1, &percent)) {
+ UserAbort:
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_USER_ABORT);
+ goto Error;
+ }
+ // Reset stats (for pure lossless coding)
+ if (picture->stats != NULL) {
+ WebPAuxStats* const stats = picture->stats;
+ memset(stats, 0, sizeof(*stats));
+ stats->PSNR[0] = 99.f;
+ stats->PSNR[1] = 99.f;
+ stats->PSNR[2] = 99.f;
+ stats->PSNR[3] = 99.f;
+ stats->PSNR[4] = 99.f;
+ }
+
+ // Write image size.
+ if (!WriteImageSize(picture, &bw)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ has_alpha = WebPPictureHasTransparency(picture);
+ // Write the non-trivial Alpha flag and lossless version.
+ if (!WriteRealAlphaAndVersion(&bw, has_alpha)) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ goto Error;
+ }
+
+ if (!WebPReportProgress(picture, 2, &percent)) goto UserAbort;
+
+ // Encode main image stream.
+ if (!VP8LEncodeStream(config, picture, &bw, 1 /*use_cache*/)) goto Error;
+
+ if (!WebPReportProgress(picture, 99, &percent)) goto UserAbort;
+
+ // Finish the RIFF chunk.
+ if (!WriteImage(picture, &bw, &coded_size)) goto Error;
+
+ if (!WebPReportProgress(picture, 100, &percent)) goto UserAbort;
+
+#if !defined(WEBP_DISABLE_STATS)
+ // Save size.
+ if (picture->stats != NULL) {
+ picture->stats->coded_size += (int)coded_size;
+ picture->stats->lossless_size = (int)coded_size;
+ }
+#endif
+
+ if (picture->extra_info != NULL) {
+ const int mb_w = (width + 15) >> 4;
+ const int mb_h = (height + 15) >> 4;
+ memset(picture->extra_info, 0, mb_w * mb_h * sizeof(*picture->extra_info));
+ }
+
+ Error:
+ if (bw.error_) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ }
+ VP8LBitWriterWipeOut(&bw);
+ return (picture->error_code == VP8_ENC_OK);
+}
+
+//------------------------------------------------------------------------------
diff --git a/media/libwebp/src/enc/vp8li_enc.h b/media/libwebp/src/enc/vp8li_enc.h
new file mode 100644
index 0000000000..3d35e1612d
--- /dev/null
+++ b/media/libwebp/src/enc/vp8li_enc.h
@@ -0,0 +1,126 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Lossless encoder: internal header.
+//
+// Author: Vikas Arora (vikaas.arora@gmail.com)
+
+#ifndef WEBP_ENC_VP8LI_ENC_H_
+#define WEBP_ENC_VP8LI_ENC_H_
+
+#ifdef HAVE_CONFIG_H
+#include "src/webp/config.h"
+#endif
+// Either WEBP_NEAR_LOSSLESS is defined as 0 in config.h when compiling to
+// disable near-lossless, or it is enabled by default.
+#ifndef WEBP_NEAR_LOSSLESS
+#define WEBP_NEAR_LOSSLESS 1
+#endif
+
+#include "src/enc/backward_references_enc.h"
+#include "src/enc/histogram_enc.h"
+#include "src/utils/bit_writer_utils.h"
+#include "src/webp/encode.h"
+#include "src/webp/format_constants.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// maximum value of transform_bits_ in VP8LEncoder.
+#define MAX_TRANSFORM_BITS 6
+
+typedef enum {
+ kEncoderNone = 0,
+ kEncoderARGB,
+ kEncoderNearLossless,
+ kEncoderPalette
+} VP8LEncoderARGBContent;
+
+typedef struct {
+ const WebPConfig* config_; // user configuration and parameters
+ const WebPPicture* pic_; // input picture.
+
+ uint32_t* argb_; // Transformed argb image data.
+ VP8LEncoderARGBContent argb_content_; // Content type of the argb buffer.
+ uint32_t* argb_scratch_; // Scratch memory for argb rows
+ // (used for prediction).
+ uint32_t* transform_data_; // Scratch memory for transform data.
+ uint32_t* transform_mem_; // Currently allocated memory.
+ size_t transform_mem_size_; // Currently allocated memory size.
+
+ int current_width_; // Corresponds to packed image width.
+
+ // Encoding parameters derived from quality parameter.
+ int histo_bits_;
+ int transform_bits_; // <= MAX_TRANSFORM_BITS.
+ int cache_bits_; // If equal to 0, don't use color cache.
+
+ // Encoding parameters derived from image characteristics.
+ int use_cross_color_;
+ int use_subtract_green_;
+ int use_predict_;
+ int use_palette_;
+ int palette_size_;
+ uint32_t palette_[MAX_PALETTE_SIZE];
+ // Sorted version of palette_ for cache purposes.
+ uint32_t palette_sorted_[MAX_PALETTE_SIZE];
+
+ // Some 'scratch' (potentially large) objects.
+ struct VP8LBackwardRefs refs_[4]; // Backward Refs array for temporaries.
+ VP8LHashChain hash_chain_; // HashChain data for constructing
+ // backward references.
+} VP8LEncoder;
+
+//------------------------------------------------------------------------------
+// internal functions. Not public.
+
+// Encodes the picture.
+// Returns 0 if config or picture is NULL or picture doesn't have valid argb
+// input.
+int VP8LEncodeImage(const WebPConfig* const config,
+ const WebPPicture* const picture);
+
+// Encodes the main image stream using the supplied bit writer.
+// If 'use_cache' is false, disables the use of color cache.
+// Returns false in case of error (stored in picture->error_code).
+int VP8LEncodeStream(const WebPConfig* const config,
+ const WebPPicture* const picture, VP8LBitWriter* const bw,
+ int use_cache);
+
+#if (WEBP_NEAR_LOSSLESS == 1)
+// in near_lossless.c
+// Near lossless preprocessing in RGB color-space.
+int VP8ApplyNearLossless(const WebPPicture* const picture, int quality,
+ uint32_t* const argb_dst);
+#endif
+
+//------------------------------------------------------------------------------
+// Image transforms in predictor.c.
+
+// pic and percent are for progress.
+// Returns false in case of error (stored in pic->error_code).
+int VP8LResidualImage(int width, int height, int bits, int low_effort,
+ uint32_t* const argb, uint32_t* const argb_scratch,
+ uint32_t* const image, int near_lossless, int exact,
+ int used_subtract_green, const WebPPicture* const pic,
+ int percent_range, int* const percent);
+
+int VP8LColorSpaceTransform(int width, int height, int bits, int quality,
+ uint32_t* const argb, uint32_t* image,
+ const WebPPicture* const pic, int percent_range,
+ int* const percent);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // WEBP_ENC_VP8LI_ENC_H_
diff --git a/media/libwebp/src/enc/webp_enc.c b/media/libwebp/src/enc/webp_enc.c
new file mode 100644
index 0000000000..9620e05070
--- /dev/null
+++ b/media/libwebp/src/enc/webp_enc.c
@@ -0,0 +1,408 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebP encoder: main entry point
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#include "src/enc/cost_enc.h"
+#include "src/enc/vp8i_enc.h"
+#include "src/enc/vp8li_enc.h"
+#include "src/utils/utils.h"
+
+// #define PRINT_MEMORY_INFO
+
+#ifdef PRINT_MEMORY_INFO
+#include <stdio.h>
+#endif
+
+//------------------------------------------------------------------------------
+
+int WebPGetEncoderVersion(void) {
+ return (ENC_MAJ_VERSION << 16) | (ENC_MIN_VERSION << 8) | ENC_REV_VERSION;
+}
+
+//------------------------------------------------------------------------------
+// VP8Encoder
+//------------------------------------------------------------------------------
+
+static void ResetSegmentHeader(VP8Encoder* const enc) {
+ VP8EncSegmentHeader* const hdr = &enc->segment_hdr_;
+ hdr->num_segments_ = enc->config_->segments;
+ hdr->update_map_ = (hdr->num_segments_ > 1);
+ hdr->size_ = 0;
+}
+
+static void ResetFilterHeader(VP8Encoder* const enc) {
+ VP8EncFilterHeader* const hdr = &enc->filter_hdr_;
+ hdr->simple_ = 1;
+ hdr->level_ = 0;
+ hdr->sharpness_ = 0;
+ hdr->i4x4_lf_delta_ = 0;
+}
+
+static void ResetBoundaryPredictions(VP8Encoder* const enc) {
+ // init boundary values once for all
+ // Note: actually, initializing the preds_[] is only needed for intra4.
+ int i;
+ uint8_t* const top = enc->preds_ - enc->preds_w_;
+ uint8_t* const left = enc->preds_ - 1;
+ for (i = -1; i < 4 * enc->mb_w_; ++i) {
+ top[i] = B_DC_PRED;
+ }
+ for (i = 0; i < 4 * enc->mb_h_; ++i) {
+ left[i * enc->preds_w_] = B_DC_PRED;
+ }
+ enc->nz_[-1] = 0; // constant
+}
+
+// Mapping from config->method_ to coding tools used.
+//-------------------+---+---+---+---+---+---+---+
+// Method | 0 | 1 | 2 | 3 |(4)| 5 | 6 |
+//-------------------+---+---+---+---+---+---+---+
+// fast probe | x | | | x | | | |
+//-------------------+---+---+---+---+---+---+---+
+// dynamic proba | ~ | x | x | x | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+// fast mode analysis|[x]|[x]| | | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+// basic rd-opt | | | | x | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+// disto-refine i4/16| x | x | x | | | | |
+//-------------------+---+---+---+---+---+---+---+
+// disto-refine uv | | x | x | | | | |
+//-------------------+---+---+---+---+---+---+---+
+// rd-opt i4/16 | | | ~ | x | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+// token buffer (opt)| | | | x | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+// Trellis | | | | | | x |Ful|
+//-------------------+---+---+---+---+---+---+---+
+// full-SNS | | | | | x | x | x |
+//-------------------+---+---+---+---+---+---+---+
+
+static void MapConfigToTools(VP8Encoder* const enc) {
+ const WebPConfig* const config = enc->config_;
+ const int method = config->method;
+ const int limit = 100 - config->partition_limit;
+ enc->method_ = method;
+ enc->rd_opt_level_ = (method >= 6) ? RD_OPT_TRELLIS_ALL
+ : (method >= 5) ? RD_OPT_TRELLIS
+ : (method >= 3) ? RD_OPT_BASIC
+ : RD_OPT_NONE;
+ enc->max_i4_header_bits_ =
+ 256 * 16 * 16 * // upper bound: up to 16bit per 4x4 block
+ (limit * limit) / (100 * 100); // ... modulated with a quadratic curve.
+
+ // partition0 = 512k max.
+ enc->mb_header_limit_ =
+ (score_t)256 * 510 * 8 * 1024 / (enc->mb_w_ * enc->mb_h_);
+
+ enc->thread_level_ = config->thread_level;
+
+ enc->do_search_ = (config->target_size > 0 || config->target_PSNR > 0);
+ if (!config->low_memory) {
+#if !defined(DISABLE_TOKEN_BUFFER)
+ enc->use_tokens_ = (enc->rd_opt_level_ >= RD_OPT_BASIC); // need rd stats
+#endif
+ if (enc->use_tokens_) {
+ enc->num_parts_ = 1; // doesn't work with multi-partition
+ }
+ }
+}
+
+// Memory scaling with dimensions:
+// memory (bytes) ~= 2.25 * w + 0.0625 * w * h
+//
+// Typical memory footprint (614x440 picture)
+// encoder: 22111
+// info: 4368
+// preds: 17741
+// top samples: 1263
+// non-zero: 175
+// lf-stats: 0
+// total: 45658
+// Transient object sizes:
+// VP8EncIterator: 3360
+// VP8ModeScore: 872
+// VP8SegmentInfo: 732
+// VP8EncProba: 18352
+// LFStats: 2048
+// Picture size (yuv): 419328
+
+static VP8Encoder* InitVP8Encoder(const WebPConfig* const config,
+ WebPPicture* const picture) {
+ VP8Encoder* enc;
+ const int use_filter =
+ (config->filter_strength > 0) || (config->autofilter > 0);
+ const int mb_w = (picture->width + 15) >> 4;
+ const int mb_h = (picture->height + 15) >> 4;
+ const int preds_w = 4 * mb_w + 1;
+ const int preds_h = 4 * mb_h + 1;
+ const size_t preds_size = preds_w * preds_h * sizeof(*enc->preds_);
+ const int top_stride = mb_w * 16;
+ const size_t nz_size = (mb_w + 1) * sizeof(*enc->nz_) + WEBP_ALIGN_CST;
+ const size_t info_size = mb_w * mb_h * sizeof(*enc->mb_info_);
+ const size_t samples_size =
+ 2 * top_stride * sizeof(*enc->y_top_) // top-luma/u/v
+ + WEBP_ALIGN_CST; // align all
+ const size_t lf_stats_size =
+ config->autofilter ? sizeof(*enc->lf_stats_) + WEBP_ALIGN_CST : 0;
+ const size_t top_derr_size =
+ (config->quality <= ERROR_DIFFUSION_QUALITY || config->pass > 1) ?
+ mb_w * sizeof(*enc->top_derr_) : 0;
+ uint8_t* mem;
+ const uint64_t size = (uint64_t)sizeof(*enc) // main struct
+ + WEBP_ALIGN_CST // cache alignment
+ + info_size // modes info
+ + preds_size // prediction modes
+ + samples_size // top/left samples
+ + top_derr_size // top diffusion error
+ + nz_size // coeff context bits
+ + lf_stats_size; // autofilter stats
+
+#ifdef PRINT_MEMORY_INFO
+ printf("===================================\n");
+ printf("Memory used:\n"
+ " encoder: %ld\n"
+ " info: %ld\n"
+ " preds: %ld\n"
+ " top samples: %ld\n"
+ " top diffusion: %ld\n"
+ " non-zero: %ld\n"
+ " lf-stats: %ld\n"
+ " total: %ld\n",
+ sizeof(*enc) + WEBP_ALIGN_CST, info_size,
+ preds_size, samples_size, top_derr_size, nz_size, lf_stats_size, size);
+ printf("Transient object sizes:\n"
+ " VP8EncIterator: %ld\n"
+ " VP8ModeScore: %ld\n"
+ " VP8SegmentInfo: %ld\n"
+ " VP8EncProba: %ld\n"
+ " LFStats: %ld\n",
+ sizeof(VP8EncIterator), sizeof(VP8ModeScore),
+ sizeof(VP8SegmentInfo), sizeof(VP8EncProba),
+ sizeof(LFStats));
+ printf("Picture size (yuv): %ld\n",
+ mb_w * mb_h * 384 * sizeof(uint8_t));
+ printf("===================================\n");
+#endif
+ mem = (uint8_t*)WebPSafeMalloc(size, sizeof(*mem));
+ if (mem == NULL) {
+ WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY);
+ return NULL;
+ }
+ enc = (VP8Encoder*)mem;
+ mem = (uint8_t*)WEBP_ALIGN(mem + sizeof(*enc));
+ memset(enc, 0, sizeof(*enc));
+ enc->num_parts_ = 1 << config->partitions;
+ enc->mb_w_ = mb_w;
+ enc->mb_h_ = mb_h;
+ enc->preds_w_ = preds_w;
+ enc->mb_info_ = (VP8MBInfo*)mem;
+ mem += info_size;
+ enc->preds_ = mem + 1 + enc->preds_w_;
+ mem += preds_size;
+ enc->nz_ = 1 + (uint32_t*)WEBP_ALIGN(mem);
+ mem += nz_size;
+ enc->lf_stats_ = lf_stats_size ? (LFStats*)WEBP_ALIGN(mem) : NULL;
+ mem += lf_stats_size;
+
+ // top samples (all 16-aligned)
+ mem = (uint8_t*)WEBP_ALIGN(mem);
+ enc->y_top_ = mem;
+ enc->uv_top_ = enc->y_top_ + top_stride;
+ mem += 2 * top_stride;
+ enc->top_derr_ = top_derr_size ? (DError*)mem : NULL;
+ mem += top_derr_size;
+ assert(mem <= (uint8_t*)enc + size);
+
+ enc->config_ = config;
+ enc->profile_ = use_filter ? ((config->filter_type == 1) ? 0 : 1) : 2;
+ enc->pic_ = picture;
+ enc->percent_ = 0;
+
+ MapConfigToTools(enc);
+ VP8EncDspInit();
+ VP8DefaultProbas(enc);
+ ResetSegmentHeader(enc);
+ ResetFilterHeader(enc);
+ ResetBoundaryPredictions(enc);
+ VP8EncDspCostInit();
+ VP8EncInitAlpha(enc);
+
+ // lower quality means smaller output -> we modulate a little the page
+ // size based on quality. This is just a crude 1rst-order prediction.
+ {
+ const float scale = 1.f + config->quality * 5.f / 100.f; // in [1,6]
+ VP8TBufferInit(&enc->tokens_, (int)(mb_w * mb_h * 4 * scale));
+ }
+ return enc;
+}
+
+static int DeleteVP8Encoder(VP8Encoder* enc) {
+ int ok = 1;
+ if (enc != NULL) {
+ ok = VP8EncDeleteAlpha(enc);
+ VP8TBufferClear(&enc->tokens_);
+ WebPSafeFree(enc);
+ }
+ return ok;
+}
+
+//------------------------------------------------------------------------------
+
+#if !defined(WEBP_DISABLE_STATS)
+static double GetPSNR(uint64_t err, uint64_t size) {
+ return (err > 0 && size > 0) ? 10. * log10(255. * 255. * size / err) : 99.;
+}
+
+static void FinalizePSNR(const VP8Encoder* const enc) {
+ WebPAuxStats* stats = enc->pic_->stats;
+ const uint64_t size = enc->sse_count_;
+ const uint64_t* const sse = enc->sse_;
+ stats->PSNR[0] = (float)GetPSNR(sse[0], size);
+ stats->PSNR[1] = (float)GetPSNR(sse[1], size / 4);
+ stats->PSNR[2] = (float)GetPSNR(sse[2], size / 4);
+ stats->PSNR[3] = (float)GetPSNR(sse[0] + sse[1] + sse[2], size * 3 / 2);
+ stats->PSNR[4] = (float)GetPSNR(sse[3], size);
+}
+#endif // !defined(WEBP_DISABLE_STATS)
+
+static void StoreStats(VP8Encoder* const enc) {
+#if !defined(WEBP_DISABLE_STATS)
+ WebPAuxStats* const stats = enc->pic_->stats;
+ if (stats != NULL) {
+ int i, s;
+ for (i = 0; i < NUM_MB_SEGMENTS; ++i) {
+ stats->segment_level[i] = enc->dqm_[i].fstrength_;
+ stats->segment_quant[i] = enc->dqm_[i].quant_;
+ for (s = 0; s <= 2; ++s) {
+ stats->residual_bytes[s][i] = enc->residual_bytes_[s][i];
+ }
+ }
+ FinalizePSNR(enc);
+ stats->coded_size = enc->coded_size_;
+ for (i = 0; i < 3; ++i) {
+ stats->block_count[i] = enc->block_count_[i];
+ }
+ }
+#else // defined(WEBP_DISABLE_STATS)
+ WebPReportProgress(enc->pic_, 100, &enc->percent_); // done!
+#endif // !defined(WEBP_DISABLE_STATS)
+}
+
+int WebPEncodingSetError(const WebPPicture* const pic,
+ WebPEncodingError error) {
+ assert((int)error < VP8_ENC_ERROR_LAST);
+ assert((int)error >= VP8_ENC_OK);
+ ((WebPPicture*)pic)->error_code = error;
+ return 0;
+}
+
+int WebPReportProgress(const WebPPicture* const pic,
+ int percent, int* const percent_store) {
+ if (percent_store != NULL && percent != *percent_store) {
+ *percent_store = percent;
+ if (pic->progress_hook && !pic->progress_hook(percent, pic)) {
+ // user abort requested
+ WebPEncodingSetError(pic, VP8_ENC_ERROR_USER_ABORT);
+ return 0;
+ }
+ }
+ return 1; // ok
+}
+//------------------------------------------------------------------------------
+
+int WebPEncode(const WebPConfig* config, WebPPicture* pic) {
+ int ok = 0;
+ if (pic == NULL) return 0;
+
+ WebPEncodingSetError(pic, VP8_ENC_OK); // all ok so far
+ if (config == NULL) { // bad params
+ return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
+ }
+ if (!WebPValidateConfig(config)) {
+ return WebPEncodingSetError(pic, VP8_ENC_ERROR_INVALID_CONFIGURATION);
+ }
+ if (!WebPValidatePicture(pic)) return 0;
+ if (pic->width > WEBP_MAX_DIMENSION || pic->height > WEBP_MAX_DIMENSION) {
+ return WebPEncodingSetError(pic, VP8_ENC_ERROR_BAD_DIMENSION);
+ }
+
+ if (pic->stats != NULL) memset(pic->stats, 0, sizeof(*pic->stats));
+
+ if (!config->lossless) {
+ VP8Encoder* enc = NULL;
+
+ if (pic->use_argb || pic->y == NULL || pic->u == NULL || pic->v == NULL) {
+ // Make sure we have YUVA samples.
+ if (config->use_sharp_yuv || (config->preprocessing & 4)) {
+ if (!WebPPictureSharpARGBToYUVA(pic)) {
+ return 0;
+ }
+ } else {
+ float dithering = 0.f;
+ if (config->preprocessing & 2) {
+ const float x = config->quality / 100.f;
+ const float x2 = x * x;
+ // slowly decreasing from max dithering at low quality (q->0)
+ // to 0.5 dithering amplitude at high quality (q->100)
+ dithering = 1.0f + (0.5f - 1.0f) * x2 * x2;
+ }
+ if (!WebPPictureARGBToYUVADithered(pic, WEBP_YUV420, dithering)) {
+ return 0;
+ }
+ }
+ }
+
+ if (!config->exact) {
+ WebPCleanupTransparentArea(pic);
+ }
+
+ enc = InitVP8Encoder(config, pic);
+ if (enc == NULL) return 0; // pic->error is already set.
+ // Note: each of the tasks below account for 20% in the progress report.
+ ok = VP8EncAnalyze(enc);
+
+ // Analysis is done, proceed to actual coding.
+ ok = ok && VP8EncStartAlpha(enc); // possibly done in parallel
+ if (!enc->use_tokens_) {
+ ok = ok && VP8EncLoop(enc);
+ } else {
+ ok = ok && VP8EncTokenLoop(enc);
+ }
+ ok = ok && VP8EncFinishAlpha(enc);
+
+ ok = ok && VP8EncWrite(enc);
+ StoreStats(enc);
+ if (!ok) {
+ VP8EncFreeBitWriters(enc);
+ }
+ ok &= DeleteVP8Encoder(enc); // must always be called, even if !ok
+ } else {
+ // Make sure we have ARGB samples.
+ if (pic->argb == NULL && !WebPPictureYUVAToARGB(pic)) {
+ return 0;
+ }
+
+ if (!config->exact) {
+ WebPReplaceTransparentPixels(pic, 0x000000);
+ }
+
+ ok = VP8LEncodeImage(config, pic); // Sets pic->error in case of problem.
+ }
+
+ return ok;
+}