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-rw-r--r--media/libwebp/src/enc/frame_enc.c899
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diff --git a/media/libwebp/src/enc/frame_enc.c b/media/libwebp/src/enc/frame_enc.c
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+// 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
+
+//------------------------------------------------------------------------------