diff options
Diffstat (limited to 'third_party/jpeg-xl/lib/jxl/epf.cc')
| -rw-r--r-- | third_party/jpeg-xl/lib/jxl/epf.cc | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/epf.cc b/third_party/jpeg-xl/lib/jxl/epf.cc new file mode 100644 index 0000000000..7288ed9ca6 --- /dev/null +++ b/third_party/jpeg-xl/lib/jxl/epf.cc @@ -0,0 +1,146 @@ +// Copyright (c) the JPEG XL Project Authors. All rights reserved. +// +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Edge-preserving smoothing: weighted average based on L1 patch similarity. + +#include "lib/jxl/epf.h" + +#include <math.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <algorithm> +#include <atomic> +#include <numeric> // std::accumulate +#include <vector> + +#include "lib/jxl/ac_strategy.h" +#include "lib/jxl/base/compiler_specific.h" +#include "lib/jxl/base/data_parallel.h" +#include "lib/jxl/base/status.h" +#include "lib/jxl/common.h" +#include "lib/jxl/convolve.h" +#include "lib/jxl/dec_cache.h" +#include "lib/jxl/image.h" +#include "lib/jxl/image_bundle.h" +#include "lib/jxl/image_ops.h" +#include "lib/jxl/loop_filter.h" +#include "lib/jxl/quant_weights.h" +#include "lib/jxl/quantizer.h" + +namespace jxl { + +// Mirror n floats starting at *p and store them before p. +JXL_INLINE void LeftMirror(float* p, size_t n) { + for (size_t i = 0; i < n; i++) { + *(p - 1 - i) = p[i]; + } +} + +// Mirror n floats starting at *(p - n) and store them at *p. +JXL_INLINE void RightMirror(float* p, size_t n) { + for (size_t i = 0; i < n; i++) { + p[i] = *(p - 1 - i); + } +} + +void ComputeSigma(const Rect& block_rect, PassesDecoderState* state) { + const LoopFilter& lf = state->shared->frame_header.loop_filter; + JXL_CHECK(lf.epf_iters > 0); + const AcStrategyImage& ac_strategy = state->shared->ac_strategy; + const float quant_scale = state->shared->quantizer.Scale(); + + const size_t sigma_stride = state->sigma.PixelsPerRow(); + const size_t sharpness_stride = state->shared->epf_sharpness.PixelsPerRow(); + + for (size_t by = 0; by < block_rect.ysize(); ++by) { + float* JXL_RESTRICT sigma_row = block_rect.Row(&state->sigma, by); + const uint8_t* JXL_RESTRICT sharpness_row = + block_rect.ConstRow(state->shared->epf_sharpness, by); + AcStrategyRow acs_row = ac_strategy.ConstRow(block_rect, by); + const int32_t* const JXL_RESTRICT row_quant = + block_rect.ConstRow(state->shared->raw_quant_field, by); + + for (size_t bx = 0; bx < block_rect.xsize(); bx++) { + AcStrategy acs = acs_row[bx]; + size_t llf_x = acs.covered_blocks_x(); + if (!acs.IsFirstBlock()) continue; + // quant_scale is smaller for low quality. + // quant_scale is roughly 0.08 / butteraugli score. + // + // row_quant is smaller for low quality. + // row_quant is a quantization multiplier of form 1.0 / + // row_quant[bx] + // + // lf.epf_quant_mul is a parameter in the format + // kInvSigmaNum is a constant + float sigma_quant = + lf.epf_quant_mul / (quant_scale * row_quant[bx] * kInvSigmaNum); + for (size_t iy = 0; iy < acs.covered_blocks_y(); iy++) { + for (size_t ix = 0; ix < acs.covered_blocks_x(); ix++) { + float sigma = + sigma_quant * + lf.epf_sharp_lut[sharpness_row[bx + ix + iy * sharpness_stride]]; + // Avoid infinities. + sigma = std::min(-1e-4f, sigma); // TODO(veluca): remove this. + sigma_row[bx + ix + kSigmaPadding + + (iy + kSigmaPadding) * sigma_stride] = 1.0f / sigma; + } + } + // TODO(veluca): remove this padding. + // Left padding with mirroring. + if (bx + block_rect.x0() == 0) { + for (size_t iy = 0; iy < acs.covered_blocks_y(); iy++) { + LeftMirror( + sigma_row + kSigmaPadding + (iy + kSigmaPadding) * sigma_stride, + kSigmaBorder); + } + } + // Right padding with mirroring. + if (bx + block_rect.x0() + llf_x == + state->shared->frame_dim.xsize_blocks) { + for (size_t iy = 0; iy < acs.covered_blocks_y(); iy++) { + RightMirror(sigma_row + kSigmaPadding + bx + llf_x + + (iy + kSigmaPadding) * sigma_stride, + kSigmaBorder); + } + } + // Offsets for row copying, in blocks. + size_t offset_before = bx + block_rect.x0() == 0 ? 1 : bx + kSigmaPadding; + size_t offset_after = + bx + block_rect.x0() + llf_x == state->shared->frame_dim.xsize_blocks + ? kSigmaPadding + llf_x + bx + kSigmaBorder + : kSigmaPadding + llf_x + bx; + size_t num = offset_after - offset_before; + // Above + if (by + block_rect.y0() == 0) { + for (size_t iy = 0; iy < kSigmaBorder; iy++) { + memcpy( + sigma_row + offset_before + + (kSigmaPadding - 1 - iy) * sigma_stride, + sigma_row + offset_before + (kSigmaPadding + iy) * sigma_stride, + num * sizeof(*sigma_row)); + } + } + // Below + if (by + block_rect.y0() + acs.covered_blocks_y() == + state->shared->frame_dim.ysize_blocks) { + for (size_t iy = 0; iy < kSigmaBorder; iy++) { + memcpy( + sigma_row + offset_before + + sigma_stride * (acs.covered_blocks_y() + kSigmaPadding + iy), + sigma_row + offset_before + + sigma_stride * + (acs.covered_blocks_y() + kSigmaPadding - 1 - iy), + num * sizeof(*sigma_row)); + } + } + } + } +} + +} // namespace jxl |