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// 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.
#include "lib/jxl/dec_group.h"
#include <algorithm>
#include <cstdint>
#include <cstring>
#include <memory>
#include <utility>
#include "lib/jxl/chroma_from_luma.h"
#include "lib/jxl/frame_header.h"
#undef HWY_TARGET_INCLUDE
#define HWY_TARGET_INCLUDE "lib/jxl/dec_group.cc"
#include <hwy/foreach_target.h>
#include <hwy/highway.h>
#include "lib/jxl/ac_context.h"
#include "lib/jxl/ac_strategy.h"
#include "lib/jxl/base/bits.h"
#include "lib/jxl/base/common.h"
#include "lib/jxl/base/printf_macros.h"
#include "lib/jxl/base/rect.h"
#include "lib/jxl/base/status.h"
#include "lib/jxl/coeff_order.h"
#include "lib/jxl/common.h" // kMaxNumPasses
#include "lib/jxl/dec_cache.h"
#include "lib/jxl/dec_transforms-inl.h"
#include "lib/jxl/dec_xyb.h"
#include "lib/jxl/entropy_coder.h"
#include "lib/jxl/quant_weights.h"
#include "lib/jxl/quantizer-inl.h"
#include "lib/jxl/quantizer.h"
#ifndef LIB_JXL_DEC_GROUP_CC
#define LIB_JXL_DEC_GROUP_CC
namespace jxl {
struct AuxOut;
// Interface for reading groups for DecodeGroupImpl.
class GetBlock {
public:
virtual void StartRow(size_t by) = 0;
virtual Status LoadBlock(size_t bx, size_t by, const AcStrategy& acs,
size_t size, size_t log2_covered_blocks,
ACPtr block[3], ACType ac_type) = 0;
virtual ~GetBlock() {}
};
// Controls whether DecodeGroupImpl renders to pixels or not.
enum DrawMode {
// Render to pixels.
kDraw = 0,
// Don't render to pixels.
kDontDraw = 1,
};
} // namespace jxl
#endif // LIB_JXL_DEC_GROUP_CC
HWY_BEFORE_NAMESPACE();
namespace jxl {
namespace HWY_NAMESPACE {
// These templates are not found via ADL.
using hwy::HWY_NAMESPACE::AllFalse;
using hwy::HWY_NAMESPACE::Gt;
using hwy::HWY_NAMESPACE::Le;
using hwy::HWY_NAMESPACE::MaskFromVec;
using hwy::HWY_NAMESPACE::Or;
using hwy::HWY_NAMESPACE::Rebind;
using hwy::HWY_NAMESPACE::ShiftRight;
using D = HWY_FULL(float);
using DU = HWY_FULL(uint32_t);
using DI = HWY_FULL(int32_t);
using DI16 = Rebind<int16_t, DI>;
using DI16_FULL = HWY_CAPPED(int16_t, kDCTBlockSize);
constexpr D d;
constexpr DI di;
constexpr DI16 di16;
constexpr DI16_FULL di16_full;
// TODO(veluca): consider SIMDfying.
void Transpose8x8InPlace(int32_t* JXL_RESTRICT block) {
for (size_t x = 0; x < 8; x++) {
for (size_t y = x + 1; y < 8; y++) {
std::swap(block[y * 8 + x], block[x * 8 + y]);
}
}
}
template <ACType ac_type>
void DequantLane(Vec<D> scaled_dequant_x, Vec<D> scaled_dequant_y,
Vec<D> scaled_dequant_b,
const float* JXL_RESTRICT dequant_matrices, size_t size,
size_t k, Vec<D> x_cc_mul, Vec<D> b_cc_mul,
const float* JXL_RESTRICT biases, ACPtr qblock[3],
float* JXL_RESTRICT block) {
const auto x_mul = Mul(Load(d, dequant_matrices + k), scaled_dequant_x);
const auto y_mul =
Mul(Load(d, dequant_matrices + size + k), scaled_dequant_y);
const auto b_mul =
Mul(Load(d, dequant_matrices + 2 * size + k), scaled_dequant_b);
Vec<DI> quantized_x_int;
Vec<DI> quantized_y_int;
Vec<DI> quantized_b_int;
if (ac_type == ACType::k16) {
Rebind<int16_t, DI> di16;
quantized_x_int = PromoteTo(di, Load(di16, qblock[0].ptr16 + k));
quantized_y_int = PromoteTo(di, Load(di16, qblock[1].ptr16 + k));
quantized_b_int = PromoteTo(di, Load(di16, qblock[2].ptr16 + k));
} else {
quantized_x_int = Load(di, qblock[0].ptr32 + k);
quantized_y_int = Load(di, qblock[1].ptr32 + k);
quantized_b_int = Load(di, qblock[2].ptr32 + k);
}
const auto dequant_x_cc =
Mul(AdjustQuantBias(di, 0, quantized_x_int, biases), x_mul);
const auto dequant_y =
Mul(AdjustQuantBias(di, 1, quantized_y_int, biases), y_mul);
const auto dequant_b_cc =
Mul(AdjustQuantBias(di, 2, quantized_b_int, biases), b_mul);
const auto dequant_x = MulAdd(x_cc_mul, dequant_y, dequant_x_cc);
const auto dequant_b = MulAdd(b_cc_mul, dequant_y, dequant_b_cc);
Store(dequant_x, d, block + k);
Store(dequant_y, d, block + size + k);
Store(dequant_b, d, block + 2 * size + k);
}
template <ACType ac_type>
void DequantBlock(const AcStrategy& acs, float inv_global_scale, int quant,
float x_dm_multiplier, float b_dm_multiplier, Vec<D> x_cc_mul,
Vec<D> b_cc_mul, AcStrategyType kind, size_t size,
const Quantizer& quantizer, size_t covered_blocks,
const size_t* sbx,
const float* JXL_RESTRICT* JXL_RESTRICT dc_row,
size_t dc_stride, const float* JXL_RESTRICT biases,
ACPtr qblock[3], float* JXL_RESTRICT block,
float* JXL_RESTRICT scratch) {
const auto scaled_dequant_s = inv_global_scale / quant;
const auto scaled_dequant_x = Set(d, scaled_dequant_s * x_dm_multiplier);
const auto scaled_dequant_y = Set(d, scaled_dequant_s);
const auto scaled_dequant_b = Set(d, scaled_dequant_s * b_dm_multiplier);
const float* dequant_matrices = quantizer.DequantMatrix(kind, 0);
for (size_t k = 0; k < covered_blocks * kDCTBlockSize; k += Lanes(d)) {
DequantLane<ac_type>(scaled_dequant_x, scaled_dequant_y, scaled_dequant_b,
dequant_matrices, size, k, x_cc_mul, b_cc_mul, biases,
qblock, block);
}
for (size_t c = 0; c < 3; c++) {
LowestFrequenciesFromDC(acs.Strategy(), dc_row[c] + sbx[c], dc_stride,
block + c * size, scratch);
}
}
Status DecodeGroupImpl(const FrameHeader& frame_header,
GetBlock* JXL_RESTRICT get_block,
GroupDecCache* JXL_RESTRICT group_dec_cache,
PassesDecoderState* JXL_RESTRICT dec_state,
size_t thread, size_t group_idx,
RenderPipelineInput& render_pipeline_input,
jpeg::JPEGData* jpeg_data, DrawMode draw) {
// TODO(veluca): investigate cache usage in this function.
const Rect block_rect =
dec_state->shared->frame_dim.BlockGroupRect(group_idx);
const AcStrategyImage& ac_strategy = dec_state->shared->ac_strategy;
const size_t xsize_blocks = block_rect.xsize();
const size_t ysize_blocks = block_rect.ysize();
const size_t dc_stride = dec_state->shared->dc->PixelsPerRow();
const float inv_global_scale = dec_state->shared->quantizer.InvGlobalScale();
const YCbCrChromaSubsampling& cs = frame_header.chroma_subsampling;
const auto kJpegDctMin = Set(di16_full, -4095);
const auto kJpegDctMax = Set(di16_full, 4095);
size_t idct_stride[3];
for (size_t c = 0; c < 3; c++) {
idct_stride[c] = render_pipeline_input.GetBuffer(c).first->PixelsPerRow();
}
HWY_ALIGN int32_t scaled_qtable[64 * 3];
ACType ac_type = dec_state->coefficients->Type();
auto dequant_block = ac_type == ACType::k16 ? DequantBlock<ACType::k16>
: DequantBlock<ACType::k32>;
// Whether or not coefficients should be stored for future usage, and/or read
// from past usage.
bool accumulate = !dec_state->coefficients->IsEmpty();
// Offset of the current block in the group.
size_t offset = 0;
std::array<int, 3> jpeg_c_map;
bool jpeg_is_gray = false;
std::array<int, 3> dcoff = {};
// TODO(veluca): all of this should be done only once per image.
const ColorCorrelation& color_correlation = dec_state->shared->cmap.base();
if (jpeg_data) {
if (!color_correlation.IsJPEGCompatible()) {
return JXL_FAILURE("The CfL map is not JPEG-compatible");
}
jpeg_is_gray = (jpeg_data->components.size() == 1);
JXL_ENSURE(frame_header.color_transform != ColorTransform::kXYB);
jpeg_c_map = JpegOrder(frame_header.color_transform, jpeg_is_gray);
const std::vector<QuantEncoding>& qe =
dec_state->shared->matrices.encodings();
if (qe.empty() || qe[0].mode != QuantEncoding::Mode::kQuantModeRAW ||
std::abs(qe[0].qraw.qtable_den - 1.f / (8 * 255)) > 1e-8f) {
return JXL_FAILURE(
"Quantization table is not a JPEG quantization table.");
}
JXL_ENSURE(qe[0].qraw.qtable->size() == 3 * 8 * 8);
int* qtable = qe[0].qraw.qtable->data();
for (size_t c = 0; c < 3; c++) {
if (frame_header.color_transform == ColorTransform::kNone) {
dcoff[c] = 1024 / qtable[64 * c];
}
for (size_t i = 0; i < 64; i++) {
// Transpose the matrix, as it will be used on the transposed block.
int n = qtable[64 + i];
int d = qtable[64 * c + i];
if (n <= 0 || d <= 0 || n >= 65536 || d >= 65536) {
return JXL_FAILURE("Invalid JPEG quantization table");
}
scaled_qtable[64 * c + (i % 8) * 8 + (i / 8)] =
(1 << kCFLFixedPointPrecision) * n / d;
}
}
}
size_t hshift[3] = {cs.HShift(0), cs.HShift(1), cs.HShift(2)};
size_t vshift[3] = {cs.VShift(0), cs.VShift(1), cs.VShift(2)};
Rect r[3];
for (size_t i = 0; i < 3; i++) {
r[i] =
Rect(block_rect.x0() >> hshift[i], block_rect.y0() >> vshift[i],
block_rect.xsize() >> hshift[i], block_rect.ysize() >> vshift[i]);
if (!r[i].IsInside({0, 0, dec_state->shared->dc->Plane(i).xsize(),
dec_state->shared->dc->Plane(i).ysize()})) {
return JXL_FAILURE("Frame dimensions are too big for the image.");
}
}
for (size_t by = 0; by < ysize_blocks; ++by) {
get_block->StartRow(by);
size_t sby[3] = {by >> vshift[0], by >> vshift[1], by >> vshift[2]};
const int32_t* JXL_RESTRICT row_quant =
block_rect.ConstRow(dec_state->shared->raw_quant_field, by);
const float* JXL_RESTRICT dc_rows[3] = {
r[0].ConstPlaneRow(*dec_state->shared->dc, 0, sby[0]),
r[1].ConstPlaneRow(*dec_state->shared->dc, 1, sby[1]),
r[2].ConstPlaneRow(*dec_state->shared->dc, 2, sby[2]),
};
const size_t ty = (block_rect.y0() + by) / kColorTileDimInBlocks;
AcStrategyRow acs_row = ac_strategy.ConstRow(block_rect, by);
const int8_t* JXL_RESTRICT row_cmap[3] = {
dec_state->shared->cmap.ytox_map.ConstRow(ty),
nullptr,
dec_state->shared->cmap.ytob_map.ConstRow(ty),
};
float* JXL_RESTRICT idct_row[3];
int16_t* JXL_RESTRICT jpeg_row[3];
for (size_t c = 0; c < 3; c++) {
const auto& buffer = render_pipeline_input.GetBuffer(c);
idct_row[c] = buffer.second.Row(buffer.first, sby[c] * kBlockDim);
if (jpeg_data) {
auto& component = jpeg_data->components[jpeg_c_map[c]];
jpeg_row[c] =
component.coeffs.data() +
(component.width_in_blocks * (r[c].y0() + sby[c]) + r[c].x0()) *
kDCTBlockSize;
}
}
size_t bx = 0;
for (size_t tx = 0; tx < DivCeil(xsize_blocks, kColorTileDimInBlocks);
tx++) {
size_t abs_tx = tx + block_rect.x0() / kColorTileDimInBlocks;
auto x_cc_mul = Set(d, color_correlation.YtoXRatio(row_cmap[0][abs_tx]));
auto b_cc_mul = Set(d, color_correlation.YtoBRatio(row_cmap[2][abs_tx]));
// Increment bx by llf_x because those iterations would otherwise
// immediately continue (!IsFirstBlock). Reduces mispredictions.
for (; bx < xsize_blocks && bx < (tx + 1) * kColorTileDimInBlocks;) {
size_t sbx[3] = {bx >> hshift[0], bx >> hshift[1], bx >> hshift[2]};
AcStrategy acs = acs_row[bx];
const size_t llf_x = acs.covered_blocks_x();
// Can only happen in the second or lower rows of a varblock.
if (JXL_UNLIKELY(!acs.IsFirstBlock())) {
bx += llf_x;
continue;
}
const size_t log2_covered_blocks = acs.log2_covered_blocks();
const size_t covered_blocks = 1 << log2_covered_blocks;
const size_t size = covered_blocks * kDCTBlockSize;
ACPtr qblock[3];
if (accumulate) {
for (size_t c = 0; c < 3; c++) {
qblock[c] = dec_state->coefficients->PlaneRow(c, group_idx, offset);
}
} else {
// No point in reading from bitstream without accumulating and not
// drawing.
JXL_ENSURE(draw == kDraw);
if (ac_type == ACType::k16) {
memset(group_dec_cache->dec_group_qblock16, 0,
size * 3 * sizeof(int16_t));
for (size_t c = 0; c < 3; c++) {
qblock[c].ptr16 = group_dec_cache->dec_group_qblock16 + c * size;
}
} else {
memset(group_dec_cache->dec_group_qblock, 0,
size * 3 * sizeof(int32_t));
for (size_t c = 0; c < 3; c++) {
qblock[c].ptr32 = group_dec_cache->dec_group_qblock + c * size;
}
}
}
JXL_RETURN_IF_ERROR(get_block->LoadBlock(
bx, by, acs, size, log2_covered_blocks, qblock, ac_type));
offset += size;
if (draw == kDontDraw) {
bx += llf_x;
continue;
}
if (JXL_UNLIKELY(jpeg_data)) {
if (acs.Strategy() != AcStrategyType::DCT) {
return JXL_FAILURE(
"Can only decode to JPEG if only DCT-8 is used.");
}
HWY_ALIGN int32_t transposed_dct_y[64];
for (size_t c : {1, 0, 2}) {
// Propagate only Y for grayscale.
if (jpeg_is_gray && c != 1) {
continue;
}
if ((sbx[c] << hshift[c] != bx) || (sby[c] << vshift[c] != by)) {
continue;
}
int16_t* JXL_RESTRICT jpeg_pos =
jpeg_row[c] + sbx[c] * kDCTBlockSize;
// JPEG XL is transposed, JPEG is not.
auto* transposed_dct = qblock[c].ptr32;
Transpose8x8InPlace(transposed_dct);
// No CfL - no need to store the y block converted to integers.
if (!cs.Is444() ||
(row_cmap[0][abs_tx] == 0 && row_cmap[2][abs_tx] == 0)) {
for (size_t i = 0; i < 64; i += Lanes(d)) {
const auto ini = Load(di, transposed_dct + i);
const auto ini16 = DemoteTo(di16, ini);
StoreU(ini16, di16, jpeg_pos + i);
}
} else if (c == 1) {
// Y channel: save for restoring X/B, but nothing else to do.
for (size_t i = 0; i < 64; i += Lanes(d)) {
const auto ini = Load(di, transposed_dct + i);
Store(ini, di, transposed_dct_y + i);
const auto ini16 = DemoteTo(di16, ini);
StoreU(ini16, di16, jpeg_pos + i);
}
} else {
// transposed_dct_y contains the y channel block, transposed.
const auto scale =
Set(di, ColorCorrelation::RatioJPEG(row_cmap[c][abs_tx]));
const auto round = Set(di, 1 << (kCFLFixedPointPrecision - 1));
for (int i = 0; i < 64; i += Lanes(d)) {
auto in = Load(di, transposed_dct + i);
auto in_y = Load(di, transposed_dct_y + i);
auto qt = Load(di, scaled_qtable + c * size + i);
auto coeff_scale = ShiftRight<kCFLFixedPointPrecision>(
Add(Mul(qt, scale), round));
auto cfl_factor = ShiftRight<kCFLFixedPointPrecision>(
Add(Mul(in_y, coeff_scale), round));
StoreU(DemoteTo(di16, Add(in, cfl_factor)), di16, jpeg_pos + i);
}
}
jpeg_pos[0] =
Clamp1<float>(dc_rows[c][sbx[c]] - dcoff[c], -2047, 2047);
auto overflow = MaskFromVec(Set(di16_full, 0));
auto underflow = MaskFromVec(Set(di16_full, 0));
for (int i = 0; i < 64; i += Lanes(di16_full)) {
auto in = LoadU(di16_full, jpeg_pos + i);
overflow = Or(overflow, Gt(in, kJpegDctMax));
underflow = Or(underflow, Lt(in, kJpegDctMin));
}
if (!AllFalse(di16_full, Or(overflow, underflow))) {
return JXL_FAILURE("JPEG DCT coefficients out of range");
}
}
} else {
HWY_ALIGN float* const block = group_dec_cache->dec_group_block;
// Dequantize and add predictions.
dequant_block(
acs, inv_global_scale, row_quant[bx], dec_state->x_dm_multiplier,
dec_state->b_dm_multiplier, x_cc_mul, b_cc_mul, acs.Strategy(),
size, dec_state->shared->quantizer,
acs.covered_blocks_y() * acs.covered_blocks_x(), sbx, dc_rows,
dc_stride,
dec_state->output_encoding_info.opsin_params.quant_biases, qblock,
block, group_dec_cache->scratch_space);
for (size_t c : {1, 0, 2}) {
if ((sbx[c] << hshift[c] != bx) || (sby[c] << vshift[c] != by)) {
continue;
}
// IDCT
float* JXL_RESTRICT idct_pos = idct_row[c] + sbx[c] * kBlockDim;
TransformToPixels(acs.Strategy(), block + c * size, idct_pos,
idct_stride[c], group_dec_cache->scratch_space);
}
}
bx += llf_x;
}
}
}
return true;
}
// NOLINTNEXTLINE(google-readability-namespace-comments)
} // namespace HWY_NAMESPACE
} // namespace jxl
HWY_AFTER_NAMESPACE();
#if HWY_ONCE
namespace jxl {
namespace {
// Decode quantized AC coefficients of DCT blocks.
// LLF components in the output block will not be modified.
template <ACType ac_type, bool uses_lz77>
Status DecodeACVarBlock(size_t ctx_offset, size_t log2_covered_blocks,
int32_t* JXL_RESTRICT row_nzeros,
const int32_t* JXL_RESTRICT row_nzeros_top,
size_t nzeros_stride, size_t c, size_t bx, size_t by,
size_t lbx, AcStrategy acs,
const coeff_order_t* JXL_RESTRICT coeff_order,
BitReader* JXL_RESTRICT br,
ANSSymbolReader* JXL_RESTRICT decoder,
const std::vector<uint8_t>& context_map,
const uint8_t* qdc_row, const int32_t* qf_row,
const BlockCtxMap& block_ctx_map, ACPtr block,
size_t shift = 0) {
// Equal to number of LLF coefficients.
const size_t covered_blocks = 1 << log2_covered_blocks;
const size_t size = covered_blocks * kDCTBlockSize;
int32_t predicted_nzeros =
PredictFromTopAndLeft(row_nzeros_top, row_nzeros, bx, 32);
size_t ord = kStrategyOrder[acs.RawStrategy()];
const coeff_order_t* JXL_RESTRICT order =
&coeff_order[CoeffOrderOffset(ord, c)];
size_t block_ctx = block_ctx_map.Context(qdc_row[lbx], qf_row[bx], ord, c);
const int32_t nzero_ctx =
block_ctx_map.NonZeroContext(predicted_nzeros, block_ctx) + ctx_offset;
size_t nzeros =
decoder->ReadHybridUintInlined<uses_lz77>(nzero_ctx, br, context_map);
if (nzeros > size - covered_blocks) {
return JXL_FAILURE("Invalid AC: nzeros %" PRIuS " too large for %" PRIuS
" 8x8 blocks",
nzeros, covered_blocks);
}
for (size_t y = 0; y < acs.covered_blocks_y(); y++) {
for (size_t x = 0; x < acs.covered_blocks_x(); x++) {
row_nzeros[bx + x + y * nzeros_stride] =
(nzeros + covered_blocks - 1) >> log2_covered_blocks;
}
}
const size_t histo_offset =
ctx_offset + block_ctx_map.ZeroDensityContextsOffset(block_ctx);
size_t prev = (nzeros > size / 16 ? 0 : 1);
for (size_t k = covered_blocks; k < size && nzeros != 0; ++k) {
const size_t ctx =
histo_offset + ZeroDensityContext(nzeros, k, covered_blocks,
log2_covered_blocks, prev);
const size_t u_coeff =
decoder->ReadHybridUintInlined<uses_lz77>(ctx, br, context_map);
// Hand-rolled version of UnpackSigned, shifting before the conversion to
// signed integer to avoid undefined behavior of shifting negative numbers.
const size_t magnitude = u_coeff >> 1;
const size_t neg_sign = (~u_coeff) & 1;
const intptr_t coeff =
static_cast<intptr_t>((magnitude ^ (neg_sign - 1)) << shift);
if (ac_type == ACType::k16) {
block.ptr16[order[k]] += coeff;
} else {
block.ptr32[order[k]] += coeff;
}
prev = static_cast<size_t>(u_coeff != 0);
nzeros -= prev;
}
if (JXL_UNLIKELY(nzeros != 0)) {
return JXL_FAILURE("Invalid AC: nzeros at end of block is %" PRIuS
", should be 0. Block (%" PRIuS ", %" PRIuS
"), channel %" PRIuS,
nzeros, bx, by, c);
}
return true;
}
// Structs used by DecodeGroupImpl to get a quantized block.
// GetBlockFromBitstream uses ANS decoding (and thus keeps track of row
// pointers in row_nzeros), GetBlockFromEncoder simply reads the coefficient
// image provided by the encoder.
struct GetBlockFromBitstream : public GetBlock {
void StartRow(size_t by) override {
qf_row = rect.ConstRow(*qf, by);
for (size_t c = 0; c < 3; c++) {
size_t sby = by >> vshift[c];
quant_dc_row = quant_dc->ConstRow(rect.y0() + by) + rect.x0();
for (size_t i = 0; i < num_passes; i++) {
row_nzeros[i][c] = group_dec_cache->num_nzeroes[i].PlaneRow(c, sby);
row_nzeros_top[i][c] =
sby == 0
? nullptr
: group_dec_cache->num_nzeroes[i].ConstPlaneRow(c, sby - 1);
}
}
}
Status LoadBlock(size_t bx, size_t by, const AcStrategy& acs, size_t size,
size_t log2_covered_blocks, ACPtr block[3],
ACType ac_type) override {
;
for (size_t c : {1, 0, 2}) {
size_t sbx = bx >> hshift[c];
size_t sby = by >> vshift[c];
if (JXL_UNLIKELY((sbx << hshift[c] != bx) || (sby << vshift[c] != by))) {
continue;
}
for (size_t pass = 0; JXL_UNLIKELY(pass < num_passes); pass++) {
auto decode_ac_varblock =
decoders[pass].UsesLZ77()
? (ac_type == ACType::k16 ? DecodeACVarBlock<ACType::k16, 1>
: DecodeACVarBlock<ACType::k32, 1>)
: (ac_type == ACType::k16 ? DecodeACVarBlock<ACType::k16, 0>
: DecodeACVarBlock<ACType::k32, 0>);
JXL_RETURN_IF_ERROR(decode_ac_varblock(
ctx_offset[pass], log2_covered_blocks, row_nzeros[pass][c],
row_nzeros_top[pass][c], nzeros_stride, c, sbx, sby, bx, acs,
&coeff_orders[pass * coeff_order_size], readers[pass],
&decoders[pass], context_map[pass], quant_dc_row, qf_row,
*block_ctx_map, block[c], shift_for_pass[pass]));
}
}
return true;
}
Status Init(const FrameHeader& frame_header,
BitReader* JXL_RESTRICT* JXL_RESTRICT readers, size_t num_passes,
size_t group_idx, size_t histo_selector_bits, const Rect& rect,
GroupDecCache* JXL_RESTRICT group_dec_cache,
PassesDecoderState* dec_state, size_t first_pass) {
for (size_t i = 0; i < 3; i++) {
hshift[i] = frame_header.chroma_subsampling.HShift(i);
vshift[i] = frame_header.chroma_subsampling.VShift(i);
}
this->coeff_order_size = dec_state->shared->coeff_order_size;
this->coeff_orders =
dec_state->shared->coeff_orders.data() + first_pass * coeff_order_size;
this->context_map = dec_state->context_map.data() + first_pass;
this->readers = readers;
this->num_passes = num_passes;
this->shift_for_pass = frame_header.passes.shift + first_pass;
this->group_dec_cache = group_dec_cache;
this->rect = rect;
block_ctx_map = &dec_state->shared->block_ctx_map;
qf = &dec_state->shared->raw_quant_field;
quant_dc = &dec_state->shared->quant_dc;
for (size_t pass = 0; pass < num_passes; pass++) {
// Select which histogram set to use among those of the current pass.
size_t cur_histogram = 0;
if (histo_selector_bits != 0) {
cur_histogram = readers[pass]->ReadBits(histo_selector_bits);
}
if (cur_histogram >= dec_state->shared->num_histograms) {
return JXL_FAILURE("Invalid histogram selector");
}
ctx_offset[pass] = cur_histogram * block_ctx_map->NumACContexts();
JXL_ASSIGN_OR_RETURN(
decoders[pass],
ANSSymbolReader::Create(&dec_state->code[pass + first_pass],
readers[pass]));
}
nzeros_stride = group_dec_cache->num_nzeroes[0].PixelsPerRow();
for (size_t i = 0; i < num_passes; i++) {
JXL_ENSURE(
nzeros_stride ==
static_cast<size_t>(group_dec_cache->num_nzeroes[i].PixelsPerRow()));
}
return true;
}
const uint32_t* shift_for_pass = nullptr; // not owned
const coeff_order_t* JXL_RESTRICT coeff_orders;
size_t coeff_order_size;
const std::vector<uint8_t>* JXL_RESTRICT context_map;
ANSSymbolReader decoders[kMaxNumPasses];
BitReader* JXL_RESTRICT* JXL_RESTRICT readers;
size_t num_passes;
size_t ctx_offset[kMaxNumPasses];
size_t nzeros_stride;
int32_t* JXL_RESTRICT row_nzeros[kMaxNumPasses][3];
const int32_t* JXL_RESTRICT row_nzeros_top[kMaxNumPasses][3];
GroupDecCache* JXL_RESTRICT group_dec_cache;
const BlockCtxMap* block_ctx_map;
const ImageI* qf;
const ImageB* quant_dc;
const int32_t* qf_row;
const uint8_t* quant_dc_row;
Rect rect;
size_t hshift[3], vshift[3];
};
struct GetBlockFromEncoder : public GetBlock {
void StartRow(size_t by) override {}
Status LoadBlock(size_t bx, size_t by, const AcStrategy& acs, size_t size,
size_t log2_covered_blocks, ACPtr block[3],
ACType ac_type) override {
JXL_ENSURE(ac_type == ACType::k32);
for (size_t c = 0; c < 3; c++) {
// for each pass
for (size_t i = 0; i < quantized_ac->size(); i++) {
for (size_t k = 0; k < size; k++) {
// TODO(veluca): SIMD.
block[c].ptr32[k] +=
rows[i][c][offset + k] * (1 << shift_for_pass[i]);
}
}
}
offset += size;
return true;
}
static StatusOr<GetBlockFromEncoder> Create(
const std::vector<std::unique_ptr<ACImage>>& ac, size_t group_idx,
const uint32_t* shift_for_pass) {
GetBlockFromEncoder result(ac, group_idx, shift_for_pass);
// TODO(veluca): not supported with chroma subsampling.
for (size_t i = 0; i < ac.size(); i++) {
JXL_ENSURE(ac[i]->Type() == ACType::k32);
for (size_t c = 0; c < 3; c++) {
result.rows[i][c] = ac[i]->PlaneRow(c, group_idx, 0).ptr32;
}
}
return result;
}
const std::vector<std::unique_ptr<ACImage>>* JXL_RESTRICT quantized_ac;
size_t offset = 0;
const int32_t* JXL_RESTRICT rows[kMaxNumPasses][3];
const uint32_t* shift_for_pass = nullptr; // not owned
private:
GetBlockFromEncoder(const std::vector<std::unique_ptr<ACImage>>& ac,
size_t group_idx, const uint32_t* shift_for_pass)
: quantized_ac(&ac), shift_for_pass(shift_for_pass) {}
};
HWY_EXPORT(DecodeGroupImpl);
} // namespace
Status DecodeGroup(const FrameHeader& frame_header,
BitReader* JXL_RESTRICT* JXL_RESTRICT readers,
size_t num_passes, size_t group_idx,
PassesDecoderState* JXL_RESTRICT dec_state,
GroupDecCache* JXL_RESTRICT group_dec_cache, size_t thread,
RenderPipelineInput& render_pipeline_input,
jpeg::JPEGData* JXL_RESTRICT jpeg_data, size_t first_pass,
bool force_draw, bool dc_only, bool* should_run_pipeline) {
JxlMemoryManager* memory_manager = dec_state->memory_manager();
DrawMode draw =
(num_passes + first_pass == frame_header.passes.num_passes) || force_draw
? kDraw
: kDontDraw;
if (should_run_pipeline) {
*should_run_pipeline = draw != kDontDraw;
}
if (draw == kDraw && num_passes == 0 && first_pass == 0) {
JXL_RETURN_IF_ERROR(group_dec_cache->InitDCBufferOnce(memory_manager));
const YCbCrChromaSubsampling& cs = frame_header.chroma_subsampling;
for (size_t c : {0, 1, 2}) {
size_t hs = cs.HShift(c);
size_t vs = cs.VShift(c);
// We reuse filter_input_storage here as it is not currently in use.
const Rect src_rect_precs =
dec_state->shared->frame_dim.BlockGroupRect(group_idx);
const Rect src_rect =
Rect(src_rect_precs.x0() >> hs, src_rect_precs.y0() >> vs,
src_rect_precs.xsize() >> hs, src_rect_precs.ysize() >> vs);
const Rect copy_rect(kRenderPipelineXOffset, 2, src_rect.xsize(),
src_rect.ysize());
JXL_RETURN_IF_ERROR(
CopyImageToWithPadding(src_rect, dec_state->shared->dc->Plane(c), 2,
copy_rect, &group_dec_cache->dc_buffer));
// Mirrorpad. Interleaving left and right padding ensures that padding
// works out correctly even for images with DC size of 1.
for (size_t y = 0; y < src_rect.ysize() + 4; y++) {
size_t xend = kRenderPipelineXOffset +
(dec_state->shared->dc->Plane(c).xsize() >> hs) -
src_rect.x0();
for (size_t ix = 0; ix < 2; ix++) {
if (src_rect.x0() == 0) {
group_dec_cache->dc_buffer.Row(y)[kRenderPipelineXOffset - ix - 1] =
group_dec_cache->dc_buffer.Row(y)[kRenderPipelineXOffset + ix];
}
if (src_rect.x0() + src_rect.xsize() + 2 >=
(dec_state->shared->dc->xsize() >> hs)) {
group_dec_cache->dc_buffer.Row(y)[xend + ix] =
group_dec_cache->dc_buffer.Row(y)[xend - ix - 1];
}
}
}
const auto& buffer = render_pipeline_input.GetBuffer(c);
Rect dst_rect = buffer.second;
ImageF* upsampling_dst = buffer.first;
JXL_ENSURE(dst_rect.IsInside(*upsampling_dst));
RenderPipelineStage::RowInfo input_rows(1, std::vector<float*>(5));
RenderPipelineStage::RowInfo output_rows(1, std::vector<float*>(8));
for (size_t y = src_rect.y0(); y < src_rect.y0() + src_rect.ysize();
y++) {
for (ssize_t iy = 0; iy < 5; iy++) {
input_rows[0][iy] = group_dec_cache->dc_buffer.Row(
Mirror(static_cast<ssize_t>(y) + iy - 2,
dec_state->shared->dc->Plane(c).ysize() >> vs) +
2 - src_rect.y0());
}
for (size_t iy = 0; iy < 8; iy++) {
output_rows[0][iy] =
dst_rect.Row(upsampling_dst, ((y - src_rect.y0()) << 3) + iy) -
kRenderPipelineXOffset;
}
// Arguments set to 0/nullptr are not used.
JXL_RETURN_IF_ERROR(dec_state->upsampler8x->ProcessRow(
input_rows, output_rows,
/*xextra=*/0, src_rect.xsize(), 0, 0, thread));
}
}
return true;
}
size_t histo_selector_bits = 0;
if (dc_only) {
JXL_ENSURE(num_passes == 0);
} else {
JXL_ENSURE(dec_state->shared->num_histograms > 0);
histo_selector_bits = CeilLog2Nonzero(dec_state->shared->num_histograms);
}
auto get_block = jxl::make_unique<GetBlockFromBitstream>();
JXL_RETURN_IF_ERROR(get_block->Init(
frame_header, readers, num_passes, group_idx, histo_selector_bits,
dec_state->shared->frame_dim.BlockGroupRect(group_idx), group_dec_cache,
dec_state, first_pass));
JXL_RETURN_IF_ERROR(HWY_DYNAMIC_DISPATCH(DecodeGroupImpl)(
frame_header, get_block.get(), group_dec_cache, dec_state, thread,
group_idx, render_pipeline_input, jpeg_data, draw));
for (size_t pass = 0; pass < num_passes; pass++) {
if (!get_block->decoders[pass].CheckANSFinalState()) {
return JXL_FAILURE("ANS checksum failure.");
}
}
return true;
}
Status DecodeGroupForRoundtrip(const FrameHeader& frame_header,
const std::vector<std::unique_ptr<ACImage>>& ac,
size_t group_idx,
PassesDecoderState* JXL_RESTRICT dec_state,
GroupDecCache* JXL_RESTRICT group_dec_cache,
size_t thread,
RenderPipelineInput& render_pipeline_input,
jpeg::JPEGData* JXL_RESTRICT jpeg_data,
AuxOut* aux_out) {
JxlMemoryManager* memory_manager = dec_state->memory_manager();
JXL_ASSIGN_OR_RETURN(
GetBlockFromEncoder get_block,
GetBlockFromEncoder::Create(ac, group_idx, frame_header.passes.shift));
JXL_RETURN_IF_ERROR(group_dec_cache->InitOnce(
memory_manager,
/*num_passes=*/0,
/*used_acs=*/(1u << AcStrategy::kNumValidStrategies) - 1));
return HWY_DYNAMIC_DISPATCH(DecodeGroupImpl)(
frame_header, &get_block, group_dec_cache, dec_state, thread, group_idx,
render_pipeline_input, jpeg_data, kDraw);
}
} // namespace jxl
#endif // HWY_ONCE