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android / platform / external / libgav1 / 9dadefb1d9dc55ab51287663bd5bb1eee145a01c / . / libgav1 / src / tile / tile.cc
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// Copyright 2019 The libgav1 Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "src/tile.h"
#include <algorithm>
#include <array>
#include <cassert>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <memory>
#include <new>
#include <numeric>
#include <type_traits>
#include <utility>
#include "src/frame_scratch_buffer.h"
#include "src/motion_vector.h"
#include "src/reconstruction.h"
#include "src/utils/bit_mask_set.h"
#include "src/utils/common.h"
#include "src/utils/constants.h"
#include "src/utils/logging.h"
#include "src/utils/segmentation.h"
#include "src/utils/stack.h"
namespace libgav1 {
namespace {
// Import all the constants in the anonymous namespace.
#include "src/quantizer_tables.inc"
#include "src/scan_tables.inc"
// Precision bits when scaling reference frames.
constexpr int kReferenceScaleShift = 14;
// Range above kNumQuantizerBaseLevels which the exponential golomb coding
// process is activated.
constexpr int kQuantizerCoefficientBaseRange = 12;
constexpr int kNumQuantizerBaseLevels = 2;
constexpr int kCoeffBaseRangeMaxIterations =
kQuantizerCoefficientBaseRange / (kCoeffBaseRangeSymbolCount - 1);
constexpr int kEntropyContextLeft = 0;
constexpr int kEntropyContextTop = 1;
constexpr uint8_t kAllZeroContextsByTopLeft[5][5] = {{1, 2, 2, 2, 3},
{2, 4, 4, 4, 5},
{2, 4, 4, 4, 5},
{2, 4, 4, 4, 5},
{3, 5, 5, 5, 6}};
// The space complexity of DFS is O(branching_factor * max_depth). For the
// parameter tree, branching_factor = 4 (there could be up to 4 children for
// every node) and max_depth (excluding the root) = 5 (to go from a 128x128
// block all the way to a 4x4 block). The worse-case stack size is 16, by
// counting the number of 'o' nodes in the diagram:
//
// | 128x128 The highest level (corresponding to the
// | root of the tree) has no node in the stack.
// |-----------------+
// | | | |
// | o o o 64x64
// |
// |-----------------+
// | | | |
// | o o o 32x32 Higher levels have three nodes in the stack,
// | because we pop one node off the stack before
// |-----------------+ pushing its four children onto the stack.
// | | | |
// | o o o 16x16
// |
// |-----------------+
// | | | |
// | o o o 8x8
// |
// |-----------------+
// | | | |
// o o o o 4x4 Only the lowest level has four nodes in the
// stack.
constexpr int kDfsStackSize = 16;
// Mask indicating whether the transform sets contain a particular transform
// type. If |tx_type| is present in |tx_set|, then the |tx_type|th LSB is set.
constexpr BitMaskSet kTransformTypeInSetMask[kNumTransformSets] = {
BitMaskSet(0x1), BitMaskSet(0xE0F), BitMaskSet(0x20F),
BitMaskSet(0xFFFF), BitMaskSet(0xFFF), BitMaskSet(0x201)};
constexpr PredictionMode
kFilterIntraModeToIntraPredictor[kNumFilterIntraPredictors] = {
kPredictionModeDc, kPredictionModeVertical, kPredictionModeHorizontal,
kPredictionModeD157, kPredictionModeDc};
// Mask used to determine the index for mode_deltas lookup.
constexpr BitMaskSet kPredictionModeDeltasMask(
kPredictionModeNearestMv, kPredictionModeNearMv, kPredictionModeNewMv,
kPredictionModeNearestNearestMv, kPredictionModeNearNearMv,
kPredictionModeNearestNewMv, kPredictionModeNewNearestMv,
kPredictionModeNearNewMv, kPredictionModeNewNearMv,
kPredictionModeNewNewMv);
// This is computed as:
// min(transform_width_log2, 5) + min(transform_height_log2, 5) - 4.
constexpr uint8_t kEobMultiSizeLookup[kNumTransformSizes] = {
0, 1, 2, 1, 2, 3, 4, 2, 3, 4, 5, 5, 4, 5, 6, 6, 5, 6, 6};
/* clang-format off */
constexpr uint8_t kCoeffBaseContextOffset[kNumTransformSizes][5][5] = {
{{0, 1, 6, 6, 0}, {1, 6, 6, 21, 0}, {6, 6, 21, 21, 0}, {6, 21, 21, 21, 0},
{0, 0, 0, 0, 0}},
{{0, 11, 11, 11, 0}, {11, 11, 11, 11, 0}, {6, 6, 21, 21, 0},
{6, 21, 21, 21, 0}, {21, 21, 21, 21, 0}},
{{0, 11, 11, 11, 0}, {11, 11, 11, 11, 0}, {6, 6, 21, 21, 0},
{6, 21, 21, 21, 0}, {21, 21, 21, 21, 0}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {0, 0, 0, 0, 0}},
{{0, 1, 6, 6, 21}, {1, 6, 6, 21, 21}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 11, 11, 11, 11}, {11, 11, 11, 11, 11}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 11, 11, 11, 11}, {11, 11, 11, 11, 11}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {0, 0, 0, 0, 0}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {16, 16, 21, 21, 21}},
{{0, 1, 6, 6, 21}, {1, 6, 6, 21, 21}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 11, 11, 11, 11}, {11, 11, 11, 11, 11}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 11, 11, 11, 11}, {11, 11, 11, 11, 11}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {16, 16, 21, 21, 21}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {16, 16, 21, 21, 21}},
{{0, 1, 6, 6, 21}, {1, 6, 6, 21, 21}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 11, 11, 11, 11}, {11, 11, 11, 11, 11}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {16, 16, 21, 21, 21}},
{{0, 16, 6, 6, 21}, {16, 16, 6, 21, 21}, {16, 16, 21, 21, 21},
{16, 16, 21, 21, 21}, {16, 16, 21, 21, 21}},
{{0, 1, 6, 6, 21}, {1, 6, 6, 21, 21}, {6, 6, 21, 21, 21},
{6, 21, 21, 21, 21}, {21, 21, 21, 21, 21}}};
/* clang-format on */
// Extended the table size from 3 to 16 by repeating the last element to avoid
// the clips to row or column indices.
constexpr uint8_t kCoeffBasePositionContextOffset[16] = {
26, 31, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36};
constexpr PredictionMode kInterIntraToIntraMode[kNumInterIntraModes] = {
kPredictionModeDc, kPredictionModeVertical, kPredictionModeHorizontal,
kPredictionModeSmooth};
// Number of horizontal luma samples before intra block copy can be used.
constexpr int kIntraBlockCopyDelayPixels = 256;
// Number of 64 by 64 blocks before intra block copy can be used.
constexpr int kIntraBlockCopyDelay64x64Blocks = kIntraBlockCopyDelayPixels / 64;
// Index [i][j] corresponds to the transform size of width 1 << (i + 2) and
// height 1 << (j + 2).
constexpr TransformSize k4x4SizeToTransformSize[5][5] = {
{kTransformSize4x4, kTransformSize4x8, kTransformSize4x16,
kNumTransformSizes, kNumTransformSizes},
{kTransformSize8x4, kTransformSize8x8, kTransformSize8x16,
kTransformSize8x32, kNumTransformSizes},
{kTransformSize16x4, kTransformSize16x8, kTransformSize16x16,
kTransformSize16x32, kTransformSize16x64},
{kNumTransformSizes, kTransformSize32x8, kTransformSize32x16,
kTransformSize32x32, kTransformSize32x64},
{kNumTransformSizes, kNumTransformSizes, kTransformSize64x16,
kTransformSize64x32, kTransformSize64x64}};
// Defined in section 9.3 of the spec.
constexpr TransformType kModeToTransformType[kIntraPredictionModesUV] = {
kTransformTypeDctDct, kTransformTypeDctAdst, kTransformTypeAdstDct,
kTransformTypeDctDct, kTransformTypeAdstAdst, kTransformTypeDctAdst,
kTransformTypeAdstDct, kTransformTypeAdstDct, kTransformTypeDctAdst,
kTransformTypeAdstAdst, kTransformTypeDctAdst, kTransformTypeAdstDct,
kTransformTypeAdstAdst, kTransformTypeDctDct};
// Defined in section 5.11.47 of the spec. This array does not contain an entry
// for kTransformSetDctOnly, so the first dimension needs to be
// |kNumTransformSets| - 1.
constexpr TransformType kInverseTransformTypeBySet[kNumTransformSets - 1][16] =
{{kTransformTypeIdentityIdentity, kTransformTypeDctDct,
kTransformTypeIdentityDct, kTransformTypeDctIdentity,
kTransformTypeAdstAdst, kTransformTypeDctAdst, kTransformTypeAdstDct},
{kTransformTypeIdentityIdentity, kTransformTypeDctDct,
kTransformTypeAdstAdst, kTransformTypeDctAdst, kTransformTypeAdstDct},
{kTransformTypeIdentityIdentity, kTransformTypeIdentityDct,
kTransformTypeDctIdentity, kTransformTypeIdentityAdst,
kTransformTypeAdstIdentity, kTransformTypeIdentityFlipadst,
kTransformTypeFlipadstIdentity, kTransformTypeDctDct,
kTransformTypeDctAdst, kTransformTypeAdstDct, kTransformTypeDctFlipadst,
kTransformTypeFlipadstDct, kTransformTypeAdstAdst,
kTransformTypeFlipadstFlipadst, kTransformTypeFlipadstAdst,
kTransformTypeAdstFlipadst},
{kTransformTypeIdentityIdentity, kTransformTypeIdentityDct,
kTransformTypeDctIdentity, kTransformTypeDctDct, kTransformTypeDctAdst,
kTransformTypeAdstDct, kTransformTypeDctFlipadst,
kTransformTypeFlipadstDct, kTransformTypeAdstAdst,
kTransformTypeFlipadstFlipadst, kTransformTypeFlipadstAdst,
kTransformTypeAdstFlipadst},
{kTransformTypeIdentityIdentity, kTransformTypeDctDct}};
// Replaces all occurrences of 64x* and *x64 with 32x* and *x32 respectively.
constexpr TransformSize kAdjustedTransformSize[kNumTransformSizes] = {
kTransformSize4x4, kTransformSize4x8, kTransformSize4x16,
kTransformSize8x4, kTransformSize8x8, kTransformSize8x16,
kTransformSize8x32, kTransformSize16x4, kTransformSize16x8,
kTransformSize16x16, kTransformSize16x32, kTransformSize16x32,
kTransformSize32x8, kTransformSize32x16, kTransformSize32x32,
kTransformSize32x32, kTransformSize32x16, kTransformSize32x32,
kTransformSize32x32};
// This is the same as Max_Tx_Size_Rect array in the spec but with *x64 and 64*x
// transforms replaced with *x32 and 32x* respectively.
constexpr TransformSize kUVTransformSize[kMaxBlockSizes] = {
kTransformSize4x4, kTransformSize4x8, kTransformSize4x16,
kTransformSize8x4, kTransformSize8x8, kTransformSize8x16,
kTransformSize8x32, kTransformSize16x4, kTransformSize16x8,
kTransformSize16x16, kTransformSize16x32, kTransformSize16x32,
kTransformSize32x8, kTransformSize32x16, kTransformSize32x32,
kTransformSize32x32, kTransformSize32x16, kTransformSize32x32,
kTransformSize32x32, kTransformSize32x32, kTransformSize32x32,
kTransformSize32x32};
// ith entry of this array is computed as:
// DivideBy2(TransformSizeToSquareTransformIndex(kTransformSizeSquareMin[i]) +
// TransformSizeToSquareTransformIndex(kTransformSizeSquareMax[i]) +
// 1)
constexpr uint8_t kTransformSizeContext[kNumTransformSizes] = {
0, 1, 1, 1, 1, 2, 2, 1, 2, 2, 3, 3, 2, 3, 3, 4, 3, 4, 4};
constexpr int8_t kSgrProjDefaultMultiplier[2] = {-32, 31};
constexpr int8_t kWienerDefaultFilter[kNumWienerCoefficients] = {3, -7, 15};
// Maps compound prediction modes into single modes. For e.g.
// kPredictionModeNearestNewMv will map to kPredictionModeNearestMv for index 0
// and kPredictionModeNewMv for index 1. It is used to simplify the logic in
// AssignMv (and avoid duplicate code). This is section 5.11.30. in the spec.
constexpr PredictionMode
kCompoundToSinglePredictionMode[kNumCompoundInterPredictionModes][2] = {
{kPredictionModeNearestMv, kPredictionModeNearestMv},
{kPredictionModeNearMv, kPredictionModeNearMv},
{kPredictionModeNearestMv, kPredictionModeNewMv},
{kPredictionModeNewMv, kPredictionModeNearestMv},
{kPredictionModeNearMv, kPredictionModeNewMv},
{kPredictionModeNewMv, kPredictionModeNearMv},
{kPredictionModeGlobalMv, kPredictionModeGlobalMv},
{kPredictionModeNewMv, kPredictionModeNewMv},
};
PredictionMode GetSinglePredictionMode(int index, PredictionMode y_mode) {
if (y_mode < kPredictionModeNearestNearestMv) {
return y_mode;
}
const int lookup_index = y_mode - kPredictionModeNearestNearestMv;
assert(lookup_index >= 0);
return kCompoundToSinglePredictionMode[lookup_index][index];
}
// log2(dqDenom) in section 7.12.3 of the spec. We use the log2 value because
// dqDenom is always a power of two and hence right shift can be used instead of
// division.
constexpr uint8_t kQuantizationShift[kNumTransformSizes] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 2, 1, 2, 2};
// Returns the minimum of |length| or |max|-|start|. This is used to clamp array
// indices when accessing arrays whose bound is equal to |max|.
int GetNumElements(int length, int start, int max) {
return std::min(length, max - start);
}
template <typename T>
void SetBlockValues(int rows, int columns, T value, T* dst, ptrdiff_t stride) {
// Specialize all columns cases (values in kTransformWidth4x4[]) for better
// performance.
switch (columns) {
case 1:
MemSetBlock<T>(rows, 1, value, dst, stride);
break;
case 2:
MemSetBlock<T>(rows, 2, value, dst, stride);
break;
case 4:
MemSetBlock<T>(rows, 4, value, dst, stride);
break;
case 8:
MemSetBlock<T>(rows, 8, value, dst, stride);
break;
default:
assert(columns == 16);
MemSetBlock<T>(rows, 16, value, dst, stride);
break;
}
}
void SetTransformType(const Tile::Block& block, int x4, int y4, int w4, int h4,
TransformType tx_type,
TransformType transform_types[32][32]) {
const int y_offset = y4 - block.row4x4;
const int x_offset = x4 - block.column4x4;
TransformType* const dst = &transform_types[y_offset][x_offset];
SetBlockValues<TransformType>(h4, w4, tx_type, dst, 32);
}
void StoreMotionFieldMvs(ReferenceFrameType reference_frame_to_store,
const MotionVector& mv_to_store, ptrdiff_t stride,
int rows, int columns,
ReferenceFrameType* reference_frame_row_start,
MotionVector* mv) {
static_assert(sizeof(*reference_frame_row_start) == sizeof(int8_t), "");
do {
// Don't switch the following two memory setting functions.
// Some ARM CPUs are quite sensitive to the order.
memset(reference_frame_row_start, reference_frame_to_store, columns);
std::fill(mv, mv + columns, mv_to_store);
reference_frame_row_start += stride;
mv += stride;
} while (--rows != 0);
}
// Inverse transform process assumes that the quantized coefficients are stored
// as a virtual 2d array of size |tx_width| x tx_height. If transform width is
// 64, then this assumption is broken because the scan order used for populating
// the coefficients for such transforms is the same as the one used for
// corresponding transform with width 32 (e.g. the scan order used for 64x16 is
// the same as the one used for 32x16). So we must restore the coefficients to
// their correct positions and clean the positions they occupied.
template <typename ResidualType>
void MoveCoefficientsForTxWidth64(int clamped_tx_height, int tx_width,
ResidualType* residual) {
if (tx_width != 64) return;
const int rows = clamped_tx_height - 2;
auto* src = residual + 32 * rows;
residual += 64 * rows;
// Process 2 rows in each loop in reverse order to avoid overwrite.
int x = rows >> 1;
do {
// The 2 rows can be processed in order.
memcpy(residual, src, 32 * sizeof(src[0]));
memcpy(residual + 64, src + 32, 32 * sizeof(src[0]));
memset(src + 32, 0, 32 * sizeof(src[0]));
src -= 64;
residual -= 128;
} while (--x);
// Process the second row. The first row is already correct.
memcpy(residual + 64, src + 32, 32 * sizeof(src[0]));
memset(src + 32, 0, 32 * sizeof(src[0]));
}
void GetClampParameters(const Tile::Block& block, int min[2], int max[2]) {
// 7.10.2.14 (part 1). (also contains implementations of 5.11.53
// and 5.11.54).
constexpr int kMvBorder4x4 = 4;
const int row_border = kMvBorder4x4 + block.height4x4;
const int column_border = kMvBorder4x4 + block.width4x4;
const int macroblocks_to_top_edge = -block.row4x4;
const int macroblocks_to_bottom_edge =
block.tile.frame_header().rows4x4 - block.height4x4 - block.row4x4;
const int macroblocks_to_left_edge = -block.column4x4;
const int macroblocks_to_right_edge =
block.tile.frame_header().columns4x4 - block.width4x4 - block.column4x4;
min[0] = MultiplyBy32(macroblocks_to_top_edge - row_border);
min[1] = MultiplyBy32(macroblocks_to_left_edge - column_border);
max[0] = MultiplyBy32(macroblocks_to_bottom_edge + row_border);
max[1] = MultiplyBy32(macroblocks_to_right_edge + column_border);
}
// Section 8.3.2 in the spec, under coeff_base_eob.
int GetCoeffBaseContextEob(TransformSize tx_size, int index) {
if (index == 0) return 0;
const TransformSize adjusted_tx_size = kAdjustedTransformSize[tx_size];
const int tx_width_log2 = kTransformWidthLog2[adjusted_tx_size];
const int tx_height = kTransformHeight[adjusted_tx_size];
if (index <= DivideBy8(tx_height << tx_width_log2)) return 1;
if (index <= DivideBy4(tx_height << tx_width_log2)) return 2;
return 3;
}
// Section 8.3.2 in the spec, under coeff_br. Optimized for end of block based
// on the fact that {0, 1}, {1, 0}, {1, 1}, {0, 2} and {2, 0} will all be 0 in
// the end of block case.
int GetCoeffBaseRangeContextEob(int adjusted_tx_width_log2, int pos,
TransformClass tx_class) {
if (pos == 0) return 0;
const int tx_width = 1 << adjusted_tx_width_log2;
const int row = pos >> adjusted_tx_width_log2;
const int column = pos & (tx_width - 1);
// This return statement is equivalent to:
// return ((tx_class == kTransformClass2D && (row | column) < 2) ||
// (tx_class == kTransformClassHorizontal && column == 0) ||
// (tx_class == kTransformClassVertical && row == 0))
// ? 7
// : 14;
return 14 >> ((static_cast<int>(tx_class == kTransformClass2D) &
static_cast<int>((row | column) < 2)) |
(tx_class & static_cast<int>(column == 0)) |
((tx_class >> 1) & static_cast<int>(row == 0)));
}
} // namespace
Tile::Tile(int tile_number, const uint8_t* const data, size_t size,
const ObuSequenceHeader& sequence_header,
const ObuFrameHeader& frame_header,
RefCountedBuffer* const current_frame, const DecoderState& state,
FrameScratchBuffer* const frame_scratch_buffer,
const WedgeMaskArray& wedge_masks,
SymbolDecoderContext* const saved_symbol_decoder_context,
const SegmentationMap* prev_segment_ids,
PostFilter* const post_filter, const dsp::Dsp* const dsp,
ThreadPool* const thread_pool,
BlockingCounterWithStatus* const pending_tiles, bool frame_parallel,
bool use_intra_prediction_buffer)
: number_(tile_number),
row_(number_ / frame_header.tile_info.tile_columns),
column_(number_ % frame_header.tile_info.tile_columns),
data_(data),
size_(size),
read_deltas_(false),
subsampling_x_{0, sequence_header.color_config.subsampling_x,
sequence_header.color_config.subsampling_x},
subsampling_y_{0, sequence_header.color_config.subsampling_y,
sequence_header.color_config.subsampling_y},
current_quantizer_index_(frame_header.quantizer.base_index),
sequence_header_(sequence_header),
frame_header_(frame_header),
reference_frame_sign_bias_(state.reference_frame_sign_bias),
reference_frames_(state.reference_frame),
motion_field_(frame_scratch_buffer->motion_field),
reference_order_hint_(state.reference_order_hint),
wedge_masks_(wedge_masks),
reader_(data_, size_, frame_header_.enable_cdf_update),
symbol_decoder_context_(frame_scratch_buffer->symbol_decoder_context),
saved_symbol_decoder_context_(saved_symbol_decoder_context),
prev_segment_ids_(prev_segment_ids),
dsp_(*dsp),
post_filter_(*post_filter),
block_parameters_holder_(frame_scratch_buffer->block_parameters_holder),
quantizer_(sequence_header_.color_config.bitdepth,
&frame_header_.quantizer),
residual_size_((sequence_header_.color_config.bitdepth == 8)
? sizeof(int16_t)
: sizeof(int32_t)),
intra_block_copy_lag_(
frame_header_.allow_intrabc
? (sequence_header_.use_128x128_superblock ? 3 : 5)
: 1),
current_frame_(*current_frame),
cdef_index_(frame_scratch_buffer->cdef_index),
inter_transform_sizes_(frame_scratch_buffer->inter_transform_sizes),
thread_pool_(thread_pool),
residual_buffer_pool_(frame_scratch_buffer->residual_buffer_pool.get()),
tile_scratch_buffer_pool_(
&frame_scratch_buffer->tile_scratch_buffer_pool),
pending_tiles_(pending_tiles),
frame_parallel_(frame_parallel),
use_intra_prediction_buffer_(use_intra_prediction_buffer),
intra_prediction_buffer_(
use_intra_prediction_buffer_
? &frame_scratch_buffer->intra_prediction_buffers.get()[row_]
: nullptr) {
row4x4_start_ = frame_header.tile_info.tile_row_start[row_];
row4x4_end_ = frame_header.tile_info.tile_row_start[row_ + 1];
column4x4_start_ = frame_header.tile_info.tile_column_start[column_];
column4x4_end_ = frame_header.tile_info.tile_column_start[column_ + 1];
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
const int block_width4x4_log2 = k4x4HeightLog2[SuperBlockSize()];
superblock_rows_ =
(row4x4_end_ - row4x4_start_ + block_width4x4 - 1) >> block_width4x4_log2;
superblock_columns_ =
(column4x4_end_ - column4x4_start_ + block_width4x4 - 1) >>
block_width4x4_log2;
// If |split_parse_and_decode_| is true, we do the necessary setup for
// splitting the parsing and the decoding steps. This is done in the following
// two cases:
// 1) If there is multi-threading within a tile (this is done if
// |thread_pool_| is not nullptr and if there are at least as many
// superblock columns as |intra_block_copy_lag_|).
// 2) If |frame_parallel| is true.
split_parse_and_decode_ = (thread_pool_ != nullptr &&
superblock_columns_ > intra_block_copy_lag_) ||
frame_parallel;
if (frame_parallel_) {
reference_frame_progress_cache_.fill(INT_MIN);
}
memset(delta_lf_, 0, sizeof(delta_lf_));
delta_lf_all_zero_ = true;
const YuvBuffer& buffer = post_filter_.frame_buffer();
for (int plane = 0; plane < PlaneCount(); ++plane) {
// Verify that the borders are big enough for Reconstruct(). max_tx_length
// is the maximum value of tx_width and tx_height for the plane.
const int max_tx_length = (plane == kPlaneY) ? 64 : 32;
// Reconstruct() may overwrite on the right. Since the right border of a
// row is followed in memory by the left border of the next row, the
// number of extra pixels to the right of a row is at least the sum of the
// left and right borders.
//
// Note: This assertion actually checks the sum of the left and right
// borders of post_filter_.GetUnfilteredBuffer(), which is a horizontally
// and vertically shifted version of |buffer|. Since the sum of the left and
// right borders is not changed by the shift, we can just check the sum of
// the left and right borders of |buffer|.
assert(buffer.left_border(plane) + buffer.right_border(plane) >=
max_tx_length - 1);
// Reconstruct() may overwrite on the bottom. We need an extra border row
// on the bottom because we need the left border of that row.
//
// Note: This assertion checks the bottom border of
// post_filter_.GetUnfilteredBuffer(). So we need to calculate the vertical
// shift that the PostFilter constructor applied to |buffer| and reduce the
// bottom border by that amount.
#ifndef NDEBUG
const int vertical_shift = static_cast<int>(
(post_filter_.GetUnfilteredBuffer(plane) - buffer.data(plane)) /
buffer.stride(plane));
const int bottom_border = buffer.bottom_border(plane) - vertical_shift;
assert(bottom_border >= max_tx_length);
#endif
// In AV1, a transform block of height H starts at a y coordinate that is
// a multiple of H. If a transform block at the bottom of the frame has
// height H, then Reconstruct() will write up to the row with index
// Align(buffer.height(plane), H) - 1. Therefore the maximum number of
// rows Reconstruct() may write to is
// Align(buffer.height(plane), max_tx_length).
buffer_[plane].Reset(Align(buffer.height(plane), max_tx_length),
buffer.stride(plane),
post_filter_.GetUnfilteredBuffer(plane));
const int plane_height =
RightShiftWithRounding(frame_header_.height, subsampling_y_[plane]);
deblock_row_limit_[plane] =
std::min(frame_header_.rows4x4, DivideBy4(plane_height + 3)
<< subsampling_y_[plane]);
const int plane_width =
RightShiftWithRounding(frame_header_.width, subsampling_x_[plane]);
deblock_column_limit_[plane] =
std::min(frame_header_.columns4x4, DivideBy4(plane_width + 3)
<< subsampling_x_[plane]);
}
}
bool Tile::Init() {
assert(coefficient_levels_.size() == dc_categories_.size());
for (size_t i = 0; i < coefficient_levels_.size(); ++i) {
const int contexts_per_plane = (i == kEntropyContextLeft)
? frame_header_.rows4x4
: frame_header_.columns4x4;
if (!coefficient_levels_[i].Reset(PlaneCount(), contexts_per_plane)) {
LIBGAV1_DLOG(ERROR, "coefficient_levels_[%zu].Reset() failed.", i);
return false;
}
if (!dc_categories_[i].Reset(PlaneCount(), contexts_per_plane)) {
LIBGAV1_DLOG(ERROR, "dc_categories_[%zu].Reset() failed.", i);
return false;
}
}
if (split_parse_and_decode_) {
assert(residual_buffer_pool_ != nullptr);
if (!residual_buffer_threaded_.Reset(superblock_rows_, superblock_columns_,
/*zero_initialize=*/false)) {
LIBGAV1_DLOG(ERROR, "residual_buffer_threaded_.Reset() failed.");
return false;
}
} else {
// Add 32 * |kResidualPaddingVertical| padding to avoid bottom boundary
// checks when parsing quantized coefficients.
residual_buffer_ = MakeAlignedUniquePtr<uint8_t>(
32, (4096 + 32 * kResidualPaddingVertical) * residual_size_);
if (residual_buffer_ == nullptr) {
LIBGAV1_DLOG(ERROR, "Allocation of residual_buffer_ failed.");
return false;
}
prediction_parameters_.reset(new (std::nothrow) PredictionParameters());
if (prediction_parameters_ == nullptr) {
LIBGAV1_DLOG(ERROR, "Allocation of prediction_parameters_ failed.");
return false;
}
}
if (frame_header_.use_ref_frame_mvs) {
assert(sequence_header_.enable_order_hint);
SetupMotionField(frame_header_, current_frame_, reference_frames_,
row4x4_start_, row4x4_end_, column4x4_start_,
column4x4_end_, &motion_field_);
}
ResetLoopRestorationParams();
return true;
}
template <ProcessingMode processing_mode, bool save_symbol_decoder_context>
bool Tile::ProcessSuperBlockRow(int row4x4,
TileScratchBuffer* const scratch_buffer) {
if (row4x4 < row4x4_start_ || row4x4 >= row4x4_end_) return true;
assert(scratch_buffer != nullptr);
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
for (int column4x4 = column4x4_start_; column4x4 < column4x4_end_;
column4x4 += block_width4x4) {
if (!ProcessSuperBlock(row4x4, column4x4, block_width4x4, scratch_buffer,
processing_mode)) {
LIBGAV1_DLOG(ERROR, "Error decoding super block row: %d column: %d",
row4x4, column4x4);
return false;
}
}
if (save_symbol_decoder_context && row4x4 + block_width4x4 >= row4x4_end_) {
SaveSymbolDecoderContext();
}
if (processing_mode == kProcessingModeDecodeOnly ||
processing_mode == kProcessingModeParseAndDecode) {
PopulateIntraPredictionBuffer(row4x4);
}
return true;
}
// Used in frame parallel mode. The symbol decoder context need not be saved in
// this case since it was done when parsing was complete.
template bool Tile::ProcessSuperBlockRow<kProcessingModeDecodeOnly, false>(
int row4x4, TileScratchBuffer* scratch_buffer);
// Used in non frame parallel mode.
template bool Tile::ProcessSuperBlockRow<kProcessingModeParseAndDecode, true>(
int row4x4, TileScratchBuffer* scratch_buffer);
void Tile::SaveSymbolDecoderContext() {
if (frame_header_.enable_frame_end_update_cdf &&
number_ == frame_header_.tile_info.context_update_id) {
*saved_symbol_decoder_context_ = symbol_decoder_context_;
}
}
bool Tile::ParseAndDecode() {
// If this is the main thread, we build the loop filter bit masks when parsing
// so that it happens in the current thread. This ensures that the main thread
// does as much work as possible.
if (split_parse_and_decode_) {
if (!ThreadedParseAndDecode()) return false;
SaveSymbolDecoderContext();
return true;
}
std::unique_ptr<TileScratchBuffer> scratch_buffer =
tile_scratch_buffer_pool_->Get();
if (scratch_buffer == nullptr) {
pending_tiles_->Decrement(false);
LIBGAV1_DLOG(ERROR, "Failed to get scratch buffer.");
return false;
}
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
for (int row4x4 = row4x4_start_; row4x4 < row4x4_end_;
row4x4 += block_width4x4) {
if (!ProcessSuperBlockRow<kProcessingModeParseAndDecode, true>(
row4x4, scratch_buffer.get())) {
pending_tiles_->Decrement(false);
return false;
}
}
tile_scratch_buffer_pool_->Release(std::move(scratch_buffer));
pending_tiles_->Decrement(true);
return true;
}
bool Tile::Parse() {
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
std::unique_ptr<TileScratchBuffer> scratch_buffer =
tile_scratch_buffer_pool_->Get();
if (scratch_buffer == nullptr) {
LIBGAV1_DLOG(ERROR, "Failed to get scratch buffer.");
return false;
}
for (int row4x4 = row4x4_start_; row4x4 < row4x4_end_;
row4x4 += block_width4x4) {
if (!ProcessSuperBlockRow<kProcessingModeParseOnly, false>(
row4x4, scratch_buffer.get())) {
return false;
}
}
tile_scratch_buffer_pool_->Release(std::move(scratch_buffer));
SaveSymbolDecoderContext();
return true;
}
bool Tile::Decode(
std::mutex* const mutex, int* const superblock_row_progress,
std::condition_variable* const superblock_row_progress_condvar) {
const int block_width4x4 = sequence_header_.use_128x128_superblock ? 32 : 16;
const int block_width4x4_log2 =
sequence_header_.use_128x128_superblock ? 5 : 4;
std::unique_ptr<TileScratchBuffer> scratch_buffer =
tile_scratch_buffer_pool_->Get();
if (scratch_buffer == nullptr) {
LIBGAV1_DLOG(ERROR, "Failed to get scratch buffer.");
return false;
}
for (int row4x4 = row4x4_start_, index = row4x4_start_ >> block_width4x4_log2;
row4x4 < row4x4_end_; row4x4 += block_width4x4, ++index) {
if (!ProcessSuperBlockRow<kProcessingModeDecodeOnly, false>(
row4x4, scratch_buffer.get())) {
return false;
}
if (post_filter_.DoDeblock()) {
// Apply vertical deblock filtering for all the columns in this tile
// except for the first 64 columns.
post_filter_.ApplyDeblockFilter(
kLoopFilterTypeVertical, row4x4,
column4x4_start_ + kNum4x4InLoopFilterUnit, column4x4_end_,
block_width4x4);
// If this is the first superblock row of the tile, then we cannot apply
// horizontal deblocking here since we don't know if the top row is
// available. So it will be done by the calling thread in that case.
if (row4x4 != row4x4_start_) {
// Apply horizontal deblock filtering for all the columns in this tile
// except for the first and the last 64 columns.
// Note about the last tile of each row: For the last tile,
// column4x4_end may not be a multiple of 16. In that case it is still
// okay to simply subtract 16 since ApplyDeblockFilter() will only do
// the filters in increments of 64 columns (or 32 columns for chroma
// with subsampling).
post_filter_.ApplyDeblockFilter(
kLoopFilterTypeHorizontal, row4x4,
column4x4_start_ + kNum4x4InLoopFilterUnit,
column4x4_end_ - kNum4x4InLoopFilterUnit, block_width4x4);
}
}
bool notify;
{
std::unique_lock<std::mutex> lock(*mutex);
notify = ++superblock_row_progress[index] ==
frame_header_.tile_info.tile_columns;
}
if (notify) {
// We are done decoding this superblock row. Notify the post filtering
// thread.
superblock_row_progress_condvar[index].notify_one();
}
}
tile_scratch_buffer_pool_->Release(std::move(scratch_buffer));
return true;
}
bool Tile::ThreadedParseAndDecode() {
{
std::lock_guard<std::mutex> lock(threading_.mutex);
if (!threading_.sb_state.Reset(superblock_rows_, superblock_columns_)) {
pending_tiles_->Decrement(false);
LIBGAV1_DLOG(ERROR, "threading.sb_state.Reset() failed.");
return false;
}
// Account for the parsing job.
++threading_.pending_jobs;
}
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
// Begin parsing.
std::unique_ptr<TileScratchBuffer> scratch_buffer =
tile_scratch_buffer_pool_->Get();
if (scratch_buffer == nullptr) {
pending_tiles_->Decrement(false);
LIBGAV1_DLOG(ERROR, "Failed to get scratch buffer.");
return false;
}
for (int row4x4 = row4x4_start_, row_index = 0; row4x4 < row4x4_end_;
row4x4 += block_width4x4, ++row_index) {
for (int column4x4 = column4x4_start_, column_index = 0;
column4x4 < column4x4_end_;
column4x4 += block_width4x4, ++column_index) {
if (!ProcessSuperBlock(row4x4, column4x4, block_width4x4,
scratch_buffer.get(), kProcessingModeParseOnly)) {
std::lock_guard<std::mutex> lock(threading_.mutex);
threading_.abort = true;
break;
}
std::unique_lock<std::mutex> lock(threading_.mutex);
if (threading_.abort) break;
threading_.sb_state[row_index][column_index] = kSuperBlockStateParsed;
// Schedule the decoding of this superblock if it is allowed.
if (CanDecode(row_index, column_index)) {
++threading_.pending_jobs;
threading_.sb_state[row_index][column_index] =
kSuperBlockStateScheduled;
lock.unlock();
thread_pool_->Schedule(
[this, row_index, column_index, block_width4x4]() {
DecodeSuperBlock(row_index, column_index, block_width4x4);
});
}
}
std::lock_guard<std::mutex> lock(threading_.mutex);
if (threading_.abort) break;
}
tile_scratch_buffer_pool_->Release(std::move(scratch_buffer));
// We are done parsing. We can return here since the calling thread will make
// sure that it waits for all the superblocks to be decoded.
//
// Finish using |threading_| before |pending_tiles_->Decrement()| because the
// Tile object could go out of scope as soon as |pending_tiles_->Decrement()|
// is called.
threading_.mutex.lock();
const bool no_pending_jobs = (--threading_.pending_jobs == 0);
const bool job_succeeded = !threading_.abort;
threading_.mutex.unlock();
if (no_pending_jobs) {
// We are done parsing and decoding this tile.
pending_tiles_->Decrement(job_succeeded);
}
return job_succeeded;
}
bool Tile::CanDecode(int row_index, int column_index) const {
assert(row_index >= 0);
assert(column_index >= 0);
// If |threading_.sb_state[row_index][column_index]| is not equal to
// kSuperBlockStateParsed, then return false. This is ok because if
// |threading_.sb_state[row_index][column_index]| is equal to:
// kSuperBlockStateNone - then the superblock is not yet parsed.
// kSuperBlockStateScheduled - then the superblock is already scheduled for
// decode.
// kSuperBlockStateDecoded - then the superblock has already been decoded.
if (row_index >= superblock_rows_ || column_index >= superblock_columns_ ||
threading_.sb_state[row_index][column_index] != kSuperBlockStateParsed) {
return false;
}
// First superblock has no dependencies.
if (row_index == 0 && column_index == 0) {
return true;
}
// Superblocks in the first row only depend on the superblock to the left of
// it.
if (row_index == 0) {
return threading_.sb_state[0][column_index - 1] == kSuperBlockStateDecoded;
}
// All other superblocks depend on superblock to the left of it (if one
// exists) and superblock to the top right with a lag of
// |intra_block_copy_lag_| (if one exists).
const int top_right_column_index =
std::min(column_index + intra_block_copy_lag_, superblock_columns_ - 1);
return threading_.sb_state[row_index - 1][top_right_column_index] ==
kSuperBlockStateDecoded &&
(column_index == 0 ||
threading_.sb_state[row_index][column_index - 1] ==
kSuperBlockStateDecoded);
}
void Tile::DecodeSuperBlock(int row_index, int column_index,
int block_width4x4) {
const int row4x4 = row4x4_start_ + (row_index * block_width4x4);
const int column4x4 = column4x4_start_ + (column_index * block_width4x4);
std::unique_ptr<TileScratchBuffer> scratch_buffer =
tile_scratch_buffer_pool_->Get();
bool ok = scratch_buffer != nullptr;
if (ok) {
ok = ProcessSuperBlock(row4x4, column4x4, block_width4x4,
scratch_buffer.get(), kProcessingModeDecodeOnly);
tile_scratch_buffer_pool_->Release(std::move(scratch_buffer));
}
std::unique_lock<std::mutex> lock(threading_.mutex);
if (ok) {
threading_.sb_state[row_index][column_index] = kSuperBlockStateDecoded;
// Candidate rows and columns that we could potentially begin the decoding
// (if it is allowed to do so). The candidates are:
// 1) The superblock to the bottom-left of the current superblock with a
// lag of |intra_block_copy_lag_| (or the beginning of the next superblock
// row in case there are less than |intra_block_copy_lag_| superblock
// columns in the Tile).
// 2) The superblock to the right of the current superblock.
const int candidate_row_indices[] = {row_index + 1, row_index};
const int candidate_column_indices[] = {
std::max(0, column_index - intra_block_copy_lag_), column_index + 1};
for (size_t i = 0; i < std::extent<decltype(candidate_row_indices)>::value;
++i) {
const int candidate_row_index = candidate_row_indices[i];
const int candidate_column_index = candidate_column_indices[i];
if (!CanDecode(candidate_row_index, candidate_column_index)) {
continue;
}
++threading_.pending_jobs;
threading_.sb_state[candidate_row_index][candidate_column_index] =
kSuperBlockStateScheduled;
lock.unlock();
thread_pool_->Schedule([this, candidate_row_index, candidate_column_index,
block_width4x4]() {
DecodeSuperBlock(candidate_row_index, candidate_column_index,
block_width4x4);
});
lock.lock();
}
} else {
threading_.abort = true;
}
// Finish using |threading_| before |pending_tiles_->Decrement()| because the
// Tile object could go out of scope as soon as |pending_tiles_->Decrement()|
// is called.
const bool no_pending_jobs = (--threading_.pending_jobs == 0);
const bool job_succeeded = !threading_.abort;
lock.unlock();
if (no_pending_jobs) {
// We are done parsing and decoding this tile.
pending_tiles_->Decrement(job_succeeded);
}
}
void Tile::PopulateIntraPredictionBuffer(int row4x4) {
const int block_width4x4 = kNum4x4BlocksWide[SuperBlockSize()];
if (!use_intra_prediction_buffer_ || row4x4 + block_width4x4 >= row4x4_end_) {
return;
}
const size_t pixel_size =
(sequence_header_.color_config.bitdepth == 8 ? sizeof(uint8_t)
: sizeof(uint16_t));
for (int plane = 0; plane < PlaneCount(); ++plane) {
const int row_to_copy =
(MultiplyBy4(row4x4 + block_width4x4) >> subsampling_y_[plane]) - 1;
const size_t pixels_to_copy =
(MultiplyBy4(column4x4_end_ - column4x4_start_) >>
subsampling_x_[plane]) *
pixel_size;
const size_t column_start =
MultiplyBy4(column4x4_start_) >> subsampling_x_[plane];
void* start;
#if LIBGAV1_MAX_BITDEPTH >= 10
if (sequence_header_.color_config.bitdepth > 8) {
Array2DView<uint16_t> buffer(
buffer_[plane].rows(), buffer_[plane].columns() / sizeof(uint16_t),
reinterpret_cast<uint16_t*>(&buffer_[plane][0][0]));
start = &buffer[row_to_copy][column_start];
} else // NOLINT
#endif
{
start = &buffer_[plane][row_to_copy][column_start];
}
memcpy((*intra_prediction_buffer_)[plane].get() + column_start * pixel_size,
start, pixels_to_copy);
}
}
int Tile::GetTransformAllZeroContext(const Block& block, Plane plane,
TransformSize tx_size, int x4, int y4,
int w4, int h4) {
const int max_x4x4 = frame_header_.columns4x4 >> subsampling_x_[plane];
const int max_y4x4 = frame_header_.rows4x4 >> subsampling_y_[plane];
const int tx_width = kTransformWidth[tx_size];
const int tx_height = kTransformHeight[tx_size];
const BlockSize plane_size = block.residual_size[plane];
const int block_width = kBlockWidthPixels[plane_size];
const int block_height = kBlockHeightPixels[plane_size];
int top = 0;
int left = 0;
const int num_top_elements = GetNumElements(w4, x4, max_x4x4);
const int num_left_elements = GetNumElements(h4, y4, max_y4x4);
if (plane == kPlaneY) {
if (block_width == tx_width && block_height == tx_height) return 0;
const uint8_t* coefficient_levels =
&coefficient_levels_[kEntropyContextTop][plane][x4];
for (int i = 0; i < num_top_elements; ++i) {
top = std::max(top, static_cast<int>(coefficient_levels[i]));
}
coefficient_levels = &coefficient_levels_[kEntropyContextLeft][plane][y4];
for (int i = 0; i < num_left_elements; ++i) {
left = std::max(left, static_cast<int>(coefficient_levels[i]));
}
assert(top <= 4);
assert(left <= 4);
// kAllZeroContextsByTopLeft is pre-computed based on the logic in the spec
// for top and left.
return kAllZeroContextsByTopLeft[top][left];
}
const uint8_t* coefficient_levels =
&coefficient_levels_[kEntropyContextTop][plane][x4];
const int8_t* dc_categories = &dc_categories_[kEntropyContextTop][plane][x4];
for (int i = 0; i < num_top_elements; ++i) {
top |= coefficient_levels[i];
top |= dc_categories[i];
}
coefficient_levels = &coefficient_levels_[kEntropyContextLeft][plane][y4];
dc_categories = &dc_categories_[kEntropyContextLeft][plane][y4];
for (int i = 0; i < num_left_elements; ++i) {
left |= coefficient_levels[i];
left |= dc_categories[i];
}
return static_cast<int>(top != 0) + static_cast<int>(left != 0) + 7 +
3 * static_cast<int>(block_width * block_height >
tx_width * tx_height);
}
TransformSet Tile::GetTransformSet(TransformSize tx_size, bool is_inter) const {
const TransformSize tx_size_square_min = kTransformSizeSquareMin[tx_size];
const TransformSize tx_size_square_max = kTransformSizeSquareMax[tx_size];
if (tx_size_square_max == kTransformSize64x64) return kTransformSetDctOnly;
if (is_inter) {
if (frame_header_.reduced_tx_set ||
tx_size_square_max == kTransformSize32x32) {
return kTransformSetInter3;
}
if (tx_size_square_min == kTransformSize16x16) return kTransformSetInter2;
return kTransformSetInter1;
}
if (tx_size_square_max == kTransformSize32x32) return kTransformSetDctOnly;
if (frame_header_.reduced_tx_set ||
tx_size_square_min == kTransformSize16x16) {
return kTransformSetIntra2;
}
return kTransformSetIntra1;
}
TransformType Tile::ComputeTransformType(const Block& block, Plane plane,
TransformSize tx_size, int block_x,
int block_y) {
const BlockParameters& bp = *block.bp;
const TransformSize tx_size_square_max = kTransformSizeSquareMax[tx_size];
if (frame_header_.segmentation.lossless[bp.segment_id] ||
tx_size_square_max == kTransformSize64x64) {
return kTransformTypeDctDct;
}
if (plane == kPlaneY) {
return transform_types_[block_y - block.row4x4][block_x - block.column4x4];
}
const TransformSet tx_set = GetTransformSet(tx_size, bp.is_inter);
TransformType tx_type;
if (bp.is_inter) {
const int x4 =
std::max(block.column4x4, block_x << subsampling_x_[kPlaneU]);
const int y4 = std::max(block.row4x4, block_y << subsampling_y_[kPlaneU]);
tx_type = transform_types_[y4 - block.row4x4][x4 - block.column4x4];
} else {
tx_type = kModeToTransformType[bp.uv_mode];
}
return kTransformTypeInSetMask[tx_set].Contains(tx_type)
? tx_type
: kTransformTypeDctDct;
}
void Tile::ReadTransformType(const Block& block, int x4, int y4,
TransformSize tx_size) {
BlockParameters& bp = *block.bp;
const TransformSet tx_set = GetTransformSet(tx_size, bp.is_inter);
TransformType tx_type = kTransformTypeDctDct;
if (tx_set != kTransformSetDctOnly &&
frame_header_.segmentation.qindex[bp.segment_id] > 0) {
const int cdf_index = SymbolDecoderContext::TxTypeIndex(tx_set);
const int cdf_tx_size_index =
TransformSizeToSquareTransformIndex(kTransformSizeSquareMin[tx_size]);
uint16_t* cdf;
if (bp.is_inter) {
cdf = symbol_decoder_context_
.inter_tx_type_cdf[cdf_index][cdf_tx_size_index];
} else {
const PredictionMode intra_direction =
block.bp->prediction_parameters->use_filter_intra
? kFilterIntraModeToIntraPredictor[block.bp->prediction_parameters
->filter_intra_mode]
: bp.y_mode;
cdf =
symbol_decoder_context_
.intra_tx_type_cdf[cdf_index][cdf_tx_size_index][intra_direction];
}
tx_type = static_cast<TransformType>(
reader_.ReadSymbol(cdf, kNumTransformTypesInSet[tx_set]));
// This array does not contain an entry for kTransformSetDctOnly, so the
// first dimension needs to be offset by 1.
tx_type = kInverseTransformTypeBySet[tx_set - 1][tx_type];
}
SetTransformType(block, x4, y4, kTransformWidth4x4[tx_size],
kTransformHeight4x4[tx_size], tx_type, transform_types_);
}
// Section 8.3.2 in the spec, under coeff_base and coeff_br.
// Bottom boundary checks are avoided by the padded rows.
// For a coefficient near the right boundary, the two right neighbors and the
// one bottom-right neighbor may be out of boundary. We don't check the right
// boundary for them, because the out of boundary neighbors project to positions
// above the diagonal line which goes through the current coefficient and these
// positions are still all 0s according to the diagonal scan order.
template <typename ResidualType>
void Tile::ReadCoeffBase2D(
const uint16_t* scan, PlaneType plane_type, TransformSize tx_size,
int clamped_tx_size_context, int adjusted_tx_width_log2, int eob,
uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1],
ResidualType* const quantized_buffer) {
const int tx_width = 1 << adjusted_tx_width_log2;
int i = eob - 2;
do {
constexpr auto threshold = static_cast<ResidualType>(3);
const uint16_t pos = scan[i];
const int row = pos >> adjusted_tx_width_log2;
const int column = pos & (tx_width - 1);
auto* const quantized = &quantized_buffer[pos];
int context;
if (pos == 0) {
context = 0;
} else {
context = std::min(
4, DivideBy2(
1 + (std::min(quantized[1], threshold) + // {0, 1}
std::min(quantized[tx_width], threshold) + // {1, 0}
std::min(quantized[tx_width + 1], threshold) + // {1, 1}
std::min(quantized[2], threshold) + // {0, 2}
std::min(quantized[MultiplyBy2(tx_width)],
threshold)))); // {2, 0}
context += kCoeffBaseContextOffset[tx_size][std::min(row, 4)]
[std::min(column, 4)];
}
int level =
reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]);
if (level > kNumQuantizerBaseLevels) {
// No need to clip quantized values to COEFF_BASE_RANGE + NUM_BASE_LEVELS
// + 1, because we clip the overall output to 6 and the unclipped
// quantized values will always result in an output of greater than 6.
context = std::min(6, DivideBy2(1 + quantized[1] + // {0, 1}
quantized[tx_width] + // {1, 0}
quantized[tx_width + 1])); // {1, 1}
if (pos != 0) {
context += 14 >> static_cast<int>((row | column) < 2);
}
level += ReadCoeffBaseRange(clamped_tx_size_context, context, plane_type);
}
quantized[0] = level;
} while (--i >= 0);
}
// Section 8.3.2 in the spec, under coeff_base and coeff_br.
// Bottom boundary checks are avoided by the padded rows.
// For a coefficient near the right boundary, the four right neighbors may be
// out of boundary. We don't do the boundary check for the first three right
// neighbors, because even for the transform blocks with smallest width 4, the
// first three out of boundary neighbors project to positions left of the
// current coefficient and these positions are still all 0s according to the
// column scan order. However, when transform block width is 4 and the current
// coefficient is on the right boundary, its fourth right neighbor projects to
// the under position on the same column, which could be nonzero. Therefore, we
// must skip the fourth right neighbor. To make it simple, for any coefficient,
// we always do the boundary check for its fourth right neighbor.
template <typename ResidualType>
void Tile::ReadCoeffBaseHorizontal(
const uint16_t* scan, PlaneType plane_type, TransformSize /*tx_size*/,
int clamped_tx_size_context, int adjusted_tx_width_log2, int eob,
uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1],
ResidualType* const quantized_buffer) {
const int tx_width = 1 << adjusted_tx_width_log2;
int i = eob - 2;
do {
constexpr auto threshold = static_cast<ResidualType>(3);
const uint16_t pos = scan[i];
const int column = pos & (tx_width - 1);
auto* const quantized = &quantized_buffer[pos];
int context = std::min(
4,
DivideBy2(1 +
(std::min(quantized[1], threshold) + // {0, 1}
std::min(quantized[tx_width], threshold) + // {1, 0}
std::min(quantized[2], threshold) + // {0, 2}
std::min(quantized[3], threshold) + // {0, 3}
std::min(quantized[4],
static_cast<ResidualType>(
(column + 4 < tx_width) ? 3 : 0))))); // {0, 4}
context += kCoeffBasePositionContextOffset[column];
int level =
reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]);
if (level > kNumQuantizerBaseLevels) {
// No need to clip quantized values to COEFF_BASE_RANGE + NUM_BASE_LEVELS
// + 1, because we clip the overall output to 6 and the unclipped
// quantized values will always result in an output of greater than 6.
context = std::min(6, DivideBy2(1 + quantized[1] + // {0, 1}
quantized[tx_width] + // {1, 0}
quantized[2])); // {0, 2}
if (pos != 0) {
context += 14 >> static_cast<int>(column == 0);
}
level += ReadCoeffBaseRange(clamped_tx_size_context, context, plane_type);
}
quantized[0] = level;
} while (--i >= 0);
}
// Section 8.3.2 in the spec, under coeff_base and coeff_br.
// Bottom boundary checks are avoided by the padded rows.
// Right boundary check is performed explicitly.
template <typename ResidualType>
void Tile::ReadCoeffBaseVertical(
const uint16_t* scan, PlaneType plane_type, TransformSize /*tx_size*/,
int clamped_tx_size_context, int adjusted_tx_width_log2, int eob,
uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1],
ResidualType* const quantized_buffer) {
const int tx_width = 1 << adjusted_tx_width_log2;
int i = eob - 2;
do {
constexpr auto threshold = static_cast<ResidualType>(3);
const uint16_t pos = scan[i];
const int row = pos >> adjusted_tx_width_log2;
const int column = pos & (tx_width - 1);
auto* const quantized = &quantized_buffer[pos];
const int quantized_column1 = (column + 1 < tx_width) ? quantized[1] : 0;
int context =
std::min(4, DivideBy2(1 + (std::min(quantized_column1, 3) + // {0, 1}
std::min(quantized[tx_width],
threshold) + // {1, 0}
std::min(quantized[MultiplyBy2(tx_width)],
threshold) + // {2, 0}
std::min(quantized[tx_width * 3],
threshold) + // {3, 0}
std::min(quantized[MultiplyBy4(tx_width)],
threshold)))); // {4, 0}
context += kCoeffBasePositionContextOffset[row];
int level =
reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]);
if (level > kNumQuantizerBaseLevels) {
// No need to clip quantized values to COEFF_BASE_RANGE + NUM_BASE_LEVELS
// + 1, because we clip the overall output to 6 and the unclipped
// quantized values will always result in an output of greater than 6.
int context =
std::min(6, DivideBy2(1 + quantized_column1 + // {0, 1}
quantized[tx_width] + // {1, 0}
quantized[MultiplyBy2(tx_width)])); // {2, 0}
if (pos != 0) {
context += 14 >> static_cast<int>(row == 0);
}
level += ReadCoeffBaseRange(clamped_tx_size_context, context, plane_type);
}
quantized[0] = level;
} while (--i >= 0);
}
int Tile::GetDcSignContext(int x4, int y4, int w4, int h4, Plane plane) {
const int max_x4x4 = frame_header_.columns4x4 >> subsampling_x_[plane];
const int8_t* dc_categories = &dc_categories_[kEntropyContextTop][plane][x4];
// Set dc_sign to 8-bit long so that std::accumulate() saves sign extension.
int8_t dc_sign = std::accumulate(
dc_categories, dc_categories + GetNumElements(w4, x4, max_x4x4), 0);
const int max_y4x4 = frame_header_.rows4x4 >> subsampling_y_[plane];
dc_categories = &dc_categories_[kEntropyContextLeft][plane][y4];
dc_sign = std::accumulate(
dc_categories, dc_categories + GetNumElements(h4, y4, max_y4x4), dc_sign);
// This return statement is equivalent to:
// if (dc_sign < 0) return 1;
// if (dc_sign > 0) return 2;
// return 0;
// And it is better than:
// return static_cast<int>(dc_sign != 0) + static_cast<int>(dc_sign > 0);
return static_cast<int>(dc_sign < 0) +
MultiplyBy2(static_cast<int>(dc_sign > 0));
}
void Tile::SetEntropyContexts(int x4, int y4, int w4, int h4, Plane plane,
uint8_t coefficient_level, int8_t dc_category) {
const int max_x4x4 = frame_header_.columns4x4 >> subsampling_x_[plane];
const int num_top_elements = GetNumElements(w4, x4, max_x4x4);
memset(&coefficient_levels_[kEntropyContextTop][plane][x4], coefficient_level,
num_top_elements);
memset(&dc_categories_[kEntropyContextTop][plane][x4], dc_category,
num_top_elements);
const int max_y4x4 = frame_header_.rows4x4 >> subsampling_y_[plane];
const int num_left_elements = GetNumElements(h4, y4, max_y4x4);
memset(&coefficient_levels_[kEntropyContextLeft][plane][y4],
coefficient_level, num_left_elements);
memset(&dc_categories_[kEntropyContextLeft][plane][y4], dc_category,
num_left_elements);
}
void Tile::ScaleMotionVector(const MotionVector& mv, const Plane plane,
const int reference_frame_index, const int x,
const int y, int* const start_x,
int* const start_y, int* const step_x,
int* const step_y) {
const int reference_upscaled_width =
(reference_frame_index == -1)
? frame_header_.upscaled_width
: reference_frames_[reference_frame_index]->upscaled_width();
const int reference_height =
(reference_frame_index == -1)
? frame_header_.height
: reference_frames_[reference_frame_index]->frame_height();
assert(2 * frame_header_.width >= reference_upscaled_width &&
2 * frame_header_.height >= reference_height &&
frame_header_.width <= 16 * reference_upscaled_width &&
frame_header_.height <= 16 * reference_height);
const bool is_scaled_x = reference_upscaled_width != frame_header_.width;
const bool is_scaled_y = reference_height != frame_header_.height;
const int half_sample = 1 << (kSubPixelBits - 1);
int orig_x = (x << kSubPixelBits) + ((2 * mv.mv[1]) >> subsampling_x_[plane]);
int orig_y = (y << kSubPixelBits) + ((2 * mv.mv[0]) >> subsampling_y_[plane]);
const int rounding_offset =
DivideBy2(1 << (kScaleSubPixelBits - kSubPixelBits));
if (is_scaled_x) {
const int scale_x = ((reference_upscaled_width << kReferenceScaleShift) +
DivideBy2(frame_header_.width)) /
frame_header_.width;
*step_x = RightShiftWithRoundingSigned(
scale_x, kReferenceScaleShift - kScaleSubPixelBits);
orig_x += half_sample;
// When frame size is 4k and above, orig_x can be above 16 bits, scale_x can
// be up to 15 bits. So we use int64_t to hold base_x.
const int64_t base_x = static_cast<int64_t>(orig_x) * scale_x -
(half_sample << kReferenceScaleShift);
*start_x =
RightShiftWithRoundingSigned(
base_x, kReferenceScaleShift + kSubPixelBits - kScaleSubPixelBits) +
rounding_offset;
} else {
*step_x = 1 << kScaleSubPixelBits;
*start_x = LeftShift(orig_x, 6) + rounding_offset;
}
if (is_scaled_y) {
const int scale_y = ((reference_height << kReferenceScaleShift) +
DivideBy2(frame_header_.height)) /
frame_header_.height;
*step_y = RightShiftWithRoundingSigned(
scale_y, kReferenceScaleShift - kScaleSubPixelBits);
orig_y += half_sample;
const int64_t base_y = static_cast<int64_t>(orig_y) * scale_y -
(half_sample << kReferenceScaleShift);
*start_y =
RightShiftWithRoundingSigned(
base_y, kReferenceScaleShift + kSubPixelBits - kScaleSubPixelBits) +
rounding_offset;
} else {
*step_y = 1 << kScaleSubPixelBits;
*start_y = LeftShift(orig_y, 6) + rounding_offset;
}
}
template <typename ResidualType, bool is_dc_coefficient>
bool Tile::ReadSignAndApplyDequantization(
const uint16_t* const scan, int i, int q_value,
const uint8_t* const quantizer_matrix, int shift, int max_value,
uint16_t* const dc_sign_cdf, int8_t* const dc_category,
int* const coefficient_level, ResidualType* residual_buffer) {
const int pos = is_dc_coefficient ? 0 : scan[i];
// If residual_buffer[pos] is zero, then the rest of the function has no
// effect.
int level = residual_buffer[pos];
if (level == 0) return true;
const int sign = is_dc_coefficient
? static_cast<int>(reader_.ReadSymbol(dc_sign_cdf))
: reader_.ReadBit();
if (level > kNumQuantizerBaseLevels + kQuantizerCoefficientBaseRange) {
int length = 0;
bool golomb_length_bit = false;
do {
golomb_length_bit = static_cast<bool>(reader_.ReadBit());
++length;
if (length > 20) {
LIBGAV1_DLOG(ERROR, "Invalid golomb_length %d", length);
return false;
}
} while (!golomb_length_bit);
int x = 1;
for (int i = length - 2; i >= 0; --i) {
x = (x << 1) | reader_.ReadBit();
}
level += x - 1;
}
if (is_dc_coefficient) {
*dc_category = (sign != 0) ? -1 : 1;
}
level &= 0xfffff;
*coefficient_level += level;
// Apply dequantization. Step 1 of section 7.12.3 in the spec.
int q = q_value;
if (quantizer_matrix != nullptr) {
q = RightShiftWithRounding(q * quantizer_matrix[pos], 5);
}
// The intermediate multiplication can exceed 32 bits, so it has to be
// performed by promoting one of the values to int64_t.
int32_t dequantized_value = (static_cast<int64_t>(q) * level) & 0xffffff;
dequantized_value >>= shift;
// At this point:
// * |dequantized_value| is always non-negative.
// * |sign| can be either 0 or 1.
// * min_value = -(max_value + 1).
// We need to apply the following:
// dequantized_value = sign ? -dequantized_value : dequantized_value;
// dequantized_value = Clip3(dequantized_value, min_value, max_value);
//
// Note that -x == ~(x - 1).
//
// Now, The above two lines can be done with a std::min and xor as follows:
dequantized_value = std::min(dequantized_value - sign, max_value) ^ -sign;
residual_buffer[pos] = dequantized_value;
return true;
}
int Tile::ReadCoeffBaseRange(int clamped_tx_size_context, int cdf_context,
int plane_type) {
int level = 0;
for (int j = 0; j < kCoeffBaseRangeMaxIterations; ++j) {
const int coeff_base_range = reader_.ReadSymbol<kCoeffBaseRangeSymbolCount>(
symbol_decoder_context_.coeff_base_range_cdf[clamped_tx_size_context]
[plane_type][cdf_context]);
level += coeff_base_range;
if (coeff_base_range < (kCoeffBaseRangeSymbolCount - 1)) break;
}
return level;
}
template <typename ResidualType>
int Tile::ReadTransformCoefficients(const Block& block, Plane plane,
int start_x, int start_y,
TransformSize tx_size,
TransformType* const tx_type) {
const int x4 = DivideBy4(start_x);
const int y4 = DivideBy4(start_y);
const int w4 = kTransformWidth4x4[tx_size];
const int h4 = kTransformHeight4x4[tx_size];
const int tx_size_context = kTransformSizeContext[tx_size];
int context =
GetTransformAllZeroContext(block, plane, tx_size, x4, y4, w4, h4);
const bool all_zero = reader_.ReadSymbol(
symbol_decoder_context_.all_zero_cdf[tx_size_context][context]);
if (all_zero) {
if (plane == kPlaneY) {
SetTransformType(block, x4, y4, w4, h4, kTransformTypeDctDct,
transform_types_);
}
SetEntropyContexts(x4, y4, w4, h4, plane, 0, 0);
// This is not used in this case, so it can be set to any value.
*tx_type = kNumTransformTypes;
return 0;
}
const int tx_width = kTransformWidth[tx_size];
const int tx_height = kTransformHeight[tx_size];
const TransformSize adjusted_tx_size = kAdjustedTransformSize[tx_size];
const int adjusted_tx_width_log2 = kTransformWidthLog2[adjusted_tx_size];
const int tx_padding =
(1 << adjusted_tx_width_log2) * kResidualPaddingVertical;
auto* residual = reinterpret_cast<ResidualType*>(*block.residual);
// Clear padding to avoid bottom boundary checks when parsing quantized
// coefficients.
memset(residual, 0, (tx_width * tx_height + tx_padding) * residual_size_);
const int clamped_tx_height = std::min(tx_height, 32);
if (plane == kPlaneY) {
ReadTransformType(block, x4, y4, tx_size);
}
BlockParameters& bp = *block.bp;
*tx_type = ComputeTransformType(block, plane, tx_size, x4, y4);
const int eob_multi_size = kEobMultiSizeLookup[tx_size];
const PlaneType plane_type = GetPlaneType(plane);
const TransformClass tx_class = GetTransformClass(*tx_type);
context = static_cast<int>(tx_class != kTransformClass2D);
uint16_t* cdf;
switch (eob_multi_size) {
case 0:
cdf = symbol_decoder_context_.eob_pt_16_cdf[plane_type][context];
break;
case 1:
cdf = symbol_decoder_context_.eob_pt_32_cdf[plane_type][context];
break;
case 2:
cdf = symbol_decoder_context_.eob_pt_64_cdf[plane_type][context];
break;
case 3:
cdf = symbol_decoder_context_.eob_pt_128_cdf[plane_type][context];
break;
case 4:
cdf = symbol_decoder_context_.eob_pt_256_cdf[plane_type][context];
break;
case 5:
cdf = symbol_decoder_context_.eob_pt_512_cdf[plane_type];
break;
case 6:
default:
cdf = symbol_decoder_context_.eob_pt_1024_cdf[plane_type];
break;
}
const int eob_pt =
1 + reader_.ReadSymbol(cdf, kEobPt16SymbolCount + eob_multi_size);
int eob = (eob_pt < 2) ? eob_pt : ((1 << (eob_pt - 2)) + 1);
if (eob_pt >= 3) {
context = eob_pt - 3;
const bool eob_extra = reader_.ReadSymbol(
symbol_decoder_context_
.eob_extra_cdf[tx_size_context][plane_type][context]);
if (eob_extra) eob += 1 << (eob_pt - 3);
for (int i = 1; i < eob_pt - 2; ++i) {
assert(eob_pt - i >= 3);
assert(eob_pt <= kEobPt1024SymbolCount);
if (static_cast<bool>(reader_.ReadBit())) {
eob += 1 << (eob_pt - i - 3);
}
}
}
const uint16_t* scan = kScan[tx_class][tx_size];
const int clamped_tx_size_context = std::min(tx_size_context, 3);
// Read the last coefficient.
{
context = GetCoeffBaseContextEob(tx_size, eob - 1);
const uint16_t pos = scan[eob - 1];
int level =
1 + reader_.ReadSymbol(
symbol_decoder_context_
.coeff_base_eob_cdf[tx_size_context][plane_type][context],
kCoeffBaseEobSymbolCount);
if (level > kNumQuantizerBaseLevels) {
level += ReadCoeffBaseRange(
clamped_tx_size_context,
GetCoeffBaseRangeContextEob(adjusted_tx_width_log2, pos, tx_class),
plane_type);
}
residual[pos] = level;
}
if (eob > 1) {
// Read all the other coefficients.
// Lookup used to call the right variant of ReadCoeffBase*() based on the
// transform class.
static constexpr void (Tile::*kGetCoeffBaseFunc[])(
const uint16_t* scan, PlaneType plane_type, TransformSize tx_size,
int clamped_tx_size_context, int adjusted_tx_width_log2, int eob,
uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1],
ResidualType* quantized_buffer) = {
&Tile::ReadCoeffBase2D<ResidualType>,
&Tile::ReadCoeffBaseHorizontal<ResidualType>,
&Tile::ReadCoeffBaseVertical<ResidualType>};
(this->*kGetCoeffBaseFunc[tx_class])(
scan, plane_type, tx_size, clamped_tx_size_context,
adjusted_tx_width_log2, eob,
symbol_decoder_context_.coeff_base_cdf[tx_size_context][plane_type],
residual);
}
const int max_value = (1 << (7 + sequence_header_.color_config.bitdepth)) - 1;
const int current_quantizer_index = GetQIndex(
frame_header_.segmentation, bp.segment_id, current_quantizer_index_);
const int dc_q_value = quantizer_.GetDcValue(plane, current_quantizer_index);
const int ac_q_value = quantizer_.GetAcValue(plane, current_quantizer_index);
const int shift = kQuantizationShift[tx_size];
const uint8_t* const quantizer_matrix =
(frame_header_.quantizer.use_matrix &&
*tx_type < kTransformTypeIdentityIdentity &&
!frame_header_.segmentation.lossless[bp.segment_id] &&
frame_header_.quantizer.matrix_level[plane] < 15)
? &kQuantizerMatrix[frame_header_.quantizer.matrix_level[plane]]
[plane_type][kQuantizerMatrixOffset[tx_size]]
: nullptr;
int coefficient_level = 0;
int8_t dc_category = 0;
uint16_t* const dc_sign_cdf =
(residual[0] != 0)
? symbol_decoder_context_.dc_sign_cdf[plane_type][GetDcSignContext(
x4, y4, w4, h4, plane)]
: nullptr;
assert(scan[0] == 0);
if (!ReadSignAndApplyDequantization<ResidualType, /*is_dc_coefficient=*/true>(
scan, 0, dc_q_value, quantizer_matrix, shift, max_value, dc_sign_cdf,
&dc_category, &coefficient_level, residual)) {
return -1;
}
if (eob > 1) {
int i = 1;
do {
if (!ReadSignAndApplyDequantization<ResidualType,
/*is_dc_coefficient=*/false>(
scan, i, ac_q_value, quantizer_matrix, shift, max_value, nullptr,
nullptr, &coefficient_level, residual)) {
return -1;
}
} while (++i < eob);
MoveCoefficientsForTxWidth64(clamped_tx_height, tx_width, residual);
}
SetEntropyContexts(x4, y4, w4, h4, plane, std::min(4, coefficient_level),
dc_category);
if (split_parse_and_decode_) {
*block.residual += tx_width * tx_height * residual_size_;
}
return eob;
}
// CALL_BITDEPTH_FUNCTION is a macro that calls the appropriate template
// |function| depending on the value of |sequence_header_.color_config.bitdepth|
// with the variadic arguments.
#if LIBGAV1_MAX_BITDEPTH >= 10
#define CALL_BITDEPTH_FUNCTION(function, ...) \
do { \
if (sequence_header_.color_config.bitdepth > 8) { \
function<uint16_t>(__VA_ARGS__); \
} else { \
function<uint8_t>(__VA_ARGS__); \
} \
} while (false)
#else
#define CALL_BITDEPTH_FUNCTION(function, ...) \
do { \
function<uint8_t>(__VA_ARGS__); \
} while (false)
#endif
bool Tile::TransformBlock(const Block& block, Plane plane, int base_x,
int base_y, TransformSize tx_size, int x, int y,
ProcessingMode mode) {
BlockParameters& bp = *block.bp;
const int subsampling_x = subsampling_x_[plane];
const int subsampling_y = subsampling_y_[plane];
const int start_x = base_x + MultiplyBy4(x);
const int start_y = base_y + MultiplyBy4(y);
const int max_x = MultiplyBy4(frame_header_.columns4x4) >> subsampling_x;
const int max_y = MultiplyBy4(frame_header_.rows4x4) >> subsampling_y;
if (start_x >= max_x || start_y >= max_y) return true;
const int row = DivideBy4(start_y << subsampling_y);
const int column = DivideBy4(start_x << subsampling_x);
const int mask = sequence_header_.use_128x128_superblock ? 31 : 15;
const int sub_block_row4x4 = row & mask;
const int sub_block_column4x4 = column & mask;
const int step_x = kTransformWidth4x4[tx_size];
const int step_y = kTransformHeight4x4[tx_size];
const bool do_decode = mode == kProcessingModeDecodeOnly ||
mode == kProcessingModeParseAndDecode;
if (do_decode && !bp.is_inter) {
if (bp.palette_mode_info.size[GetPlaneType(plane)] > 0) {
CALL_BITDEPTH_FUNCTION(PalettePrediction, block, plane, start_x, start_y,
x, y, tx_size);
} else {
const PredictionMode mode =
(plane == kPlaneY)
? bp.y_mode
: (bp.uv_mode == kPredictionModeChromaFromLuma ? kPredictionModeDc
: bp.uv_mode);
const int tr_row4x4 = (sub_block_row4x4 >> subsampling_y);
const int tr_column4x4 =
(sub_block_column4x4 >> subsampling_x) + step_x + 1;
const int bl_row4x4 = (sub_block_row4x4 >> subsampling_y) + step_y + 1;
const int bl_column4x4 = (sub_block_column4x4 >> subsampling_x);
const bool has_left = x > 0 || block.left_available[plane];
const bool has_top = y > 0 || block.top_available[plane];
CALL_BITDEPTH_FUNCTION(
IntraPrediction, block, plane, start_x, start_y, has_left, has_top,
block.scratch_buffer->block_decoded[plane][tr_row4x4][tr_column4x4],
block.scratch_buffer->block_decoded[plane][bl_row4x4][bl_column4x4],
mode, tx_size);
if (plane != kPlaneY && bp.uv_mode == kPredictionModeChromaFromLuma) {
CALL_BITDEPTH_FUNCTION(ChromaFromLumaPrediction, block, plane, start_x,
start_y, tx_size);
}
}
if (plane == kPlaneY) {
block.bp->prediction_parameters->max_luma_width =
start_x + MultiplyBy4(step_x);
block.bp->prediction_parameters->max_luma_height =
start_y + MultiplyBy4(step_y);
block.scratch_buffer->cfl_luma_buffer_valid = false;
}
}
if (!bp.skip) {
const int sb_row_index = SuperBlockRowIndex(block.row4x4);
const int sb_column_index = SuperBlockColumnIndex(block.column4x4);
if (mode == kProcessingModeDecodeOnly) {
TransformParameterQueue& tx_params =
*residual_buffer_threaded_[sb_row_index][sb_column_index]
->transform_parameters();
ReconstructBlock(block, plane, start_x, start_y, tx_size,
tx_params.Type(), tx_params.NonZeroCoeffCount());
tx_params.Pop();
} else {
TransformType tx_type;
int non_zero_coeff_count;
#if LIBGAV1_MAX_BITDEPTH >= 10
if (sequence_header_.color_config.bitdepth > 8) {
non_zero_coeff_count = ReadTransformCoefficients<int32_t>(
block, plane, start_x, start_y, tx_size, &tx_type);
} else // NOLINT
#endif
{
non_zero_coeff_count = ReadTransformCoefficients<int16_t>(
block, plane, start_x, start_y, tx_size, &tx_type);
}
if (non_zero_coeff_count < 0) return false;
if (mode == kProcessingModeParseAndDecode) {
ReconstructBlock(block, plane, start_x, start_y, tx_size, tx_type,
non_zero_coeff_count);
} else {
assert(mode == kProcessingModeParseOnly);
residual_buffer_threaded_[sb_row_index][sb_column_index]
->transform_parameters()
->Push(non_zero_coeff_count, tx_type);
}
}
}
if (do_decode) {
bool* block_decoded =
&block.scratch_buffer
->block_decoded[plane][(sub_block_row4x4 >> subsampling_y) + 1]
[(sub_block_column4x4 >> subsampling_x) + 1];
SetBlockValues<bool>(step_y, step_x, true, block_decoded,
TileScratchBuffer::kBlockDecodedStride);
}
return true;
}
bool Tile::TransformTree(const Block& block, int start_x, int start_y,
BlockSize plane_size, ProcessingMode mode) {
assert(plane_size <= kBlock64x64);
// Branching factor is 4; Maximum Depth is 4; So the maximum stack size
// required is (4 - 1) * 4 + 1 = 13.
Stack<TransformTreeNode, 13> stack;
// It is okay to cast BlockSize to TransformSize here since the enum are
// equivalent for all BlockSize values <= kBlock64x64.
stack.Push(TransformTreeNode(start_x, start_y,
static_cast<TransformSize>(plane_size)));
do {
TransformTreeNode node = stack.Pop();
const int row = DivideBy4(node.y);
const int column = DivideBy4(node.x);
if (row >= frame_header_.rows4x4 || column >= frame_header_.columns4x4) {
continue;
}
const TransformSize inter_tx_size = inter_transform_sizes_[row][column];
const int width = kTransformWidth[node.tx_size];
const int height = kTransformHeight[node.tx_size];
if (width <= kTransformWidth[inter_tx_size] &&
height <= kTransformHeight[inter_tx_size]) {
if (!TransformBlock(block, kPlaneY, node.x, node.y, node.tx_size, 0, 0,
mode)) {
return false;
}
continue;
}
// The split transform size look up gives the right transform size that we
// should push in the stack.
// if (width > height) => transform size whose width is half.
// if (width < height) => transform size whose height is half.
// if (width == height) => transform size whose width and height are half.
const TransformSize split_tx_size = kSplitTransformSize[node.tx_size];
const int half_width = DivideBy2(width);
if (width > height) {
stack.Push(TransformTreeNode(node.x + half_width, node.y, split_tx_size));
stack.Push(TransformTreeNode(node.x, node.y, split_tx_size));
continue;
}
const int half_height = DivideBy2(height);
if (width < height) {
stack.Push(
TransformTreeNode(node.x, node.y + half_height, split_tx_size));
stack.Push(TransformTreeNode(node.x, node.y, split_tx_size));
continue;
}
stack.Push(TransformTreeNode(node.x + half_width, node.y + half_height,
split_tx_size));
stack.Push(TransformTreeNode(node.x, node.y + half_height, split_tx_size));
stack.Push(TransformTreeNode(node.x + half_width, node.y, split_tx_size));
stack.Push(TransformTreeNode(node.x, node.y, split_tx_size));
} while (!stack.Empty());
return true;
}
void Tile::ReconstructBlock(const Block& block, Plane plane, int start_x,
int start_y, TransformSize tx_size,
TransformType tx_type, int non_zero_coeff_count) {
// Reconstruction process. Steps 2 and 3 of Section 7.12.3 in the spec.
assert(non_zero_coeff_count >= 0);
if (non_zero_coeff_count == 0) return;
#if LIBGAV1_MAX_BITDEPTH >= 10
if (sequence_header_.color_config.bitdepth > 8) {
Array2DView<uint16_t> buffer(
buffer_[plane].rows(), buffer_[plane].columns() / sizeof(uint16_t),
reinterpret_cast<uint16_t*>(&buffer_[plane][0][0]));
Reconstruct(dsp_, tx_type, tx_size,
frame_header_.segmentation.lossless[block.bp->segment_id],
reinterpret_cast<int32_t*>(*block.residual), start_x, start_y,
&buffer, non_zero_coeff_count);
} else // NOLINT
#endif
{
Reconstruct(dsp_, tx_type, tx_size,
frame_header_.segmentation.lossless[block.bp->segment_id],
reinterpret_cast<int16_t*>(*block.residual), start_x, start_y,
&buffer_[plane], non_zero_coeff_count);
}
if (split_parse_and_decode_) {
*block.residual +=
kTransformWidth[tx_size] * kTransformHeight[tx_size] * residual_size_;
}
}
bool Tile::Residual(const Block& block, ProcessingMode mode) {
const int width_chunks = std::max(1, block.width >> 6);
const int height_chunks = std::max(1, block.height >> 6);
const BlockSize size_chunk4x4 =
(width_chunks > 1 || height_chunks > 1) ? kBlock64x64 : block.size;
const BlockParameters& bp = *block.bp;
for (int chunk_y = 0; chunk_y < height_chunks; ++chunk_y) {
for (int chunk_x = 0; chunk_x < width_chunks; ++chunk_x) {
for (int plane = 0; plane < (block.HasChroma() ? PlaneCount() : 1);
++plane) {
const int subsampling_x = subsampling_x_[plane];
const int subsampling_y = subsampling_y_[plane];
// For Y Plane, when lossless is true |bp.transform_size| is always
// kTransformSize4x4. So we can simply use |bp.transform_size| here as
// the Y plane's transform size (part of Section 5.11.37 in the spec).
const TransformSize tx_size =
(plane == kPlaneY) ? bp.transform_size : bp.uv_transform_size;
const BlockSize plane_size =
kPlaneResidualSize[size_chunk4x4][subsampling_x][subsampling_y];
assert(plane_size != kBlockInvalid);
if (bp.is_inter &&
!frame_header_.segmentation.lossless[bp.segment_id] &&
plane == kPlaneY) {
const int row_chunk4x4 = block.row4x4 + MultiplyBy16(chunk_y);
const int column_chunk4x4 = block.column4x4 + MultiplyBy16(chunk_x);
const int base_x = MultiplyBy4(column_chunk4x4 >> subsampling_x);
const int base_y = MultiplyBy4(row_chunk4x4 >> subsampling_y);
if (!TransformTree(block, base_x, base_y, plane_size, mode)) {
return false;
}
} else {
const int base_x = MultiplyBy4(block.column4x4 >> subsampling_x);
const int base_y = MultiplyBy4(block.row4x4 >> subsampling_y);
const int step_x = kTransformWidth4x4[tx_size];
const int step_y = kTransformHeight4x4[tx_size];
const int num4x4_wide = kNum4x4BlocksWide[plane_size];
const int num4x4_high = kNum4x4BlocksHigh[plane_size];
for (int y = 0; y < num4x4_high; y += step_y) {
for (int x = 0; x < num4x4_wide; x += step_x) {
if (!TransformBlock(
block, static_cast<Plane>(plane), base_x, base_y, tx_size,
x + (MultiplyBy16(chunk_x) >> subsampling_x),
y + (MultiplyBy16(chunk_y) >> subsampling_y), mode)) {
return false;
}
}
}
}
}
}
}
return true;
}
// The purpose of this function is to limit the maximum size of motion vectors
// and also, if use_intra_block_copy is true, to additionally constrain the
// motion vector so that the data is fetched from parts of the tile that have
// already been decoded and are not too close to the current block (in order to
// make a pipelined decoder implementation feasible).
bool Tile::IsMvValid(const Block& block, bool is_compound) const {
const BlockParameters& bp = *block.bp;
for (int i = 0; i < 1 + static_cast<int>(is_compound); ++i) {
for (int mv_component : bp.mv.mv[i].mv) {
if (std::abs(mv_component) >= (1 << 14)) {
return false;
}
}
}
if (!block.bp->prediction_parameters->use_intra_block_copy) {
return true;
}
if ((bp.mv.mv[0].mv32 & 0x00070007) != 0) {
return false;
}
const int delta_row = bp.mv.mv[0].mv[0] >> 3;
const int delta_column = bp.mv.mv[0].mv[1] >> 3;
int src_top_edge = MultiplyBy4(block.row4x4) + delta_row;
int src_left_edge = MultiplyBy4(block.column4x4) + delta_column;
const int src_bottom_edge = src_top_edge + block.height;
const int src_right_edge = src_left_edge + block.width;
if (block.HasChroma()) {
if (block.width < 8 && subsampling_x_[kPlaneU] != 0) {
src_left_edge -= 4;
}
if (block.height < 8 && subsampling_y_[kPlaneU] != 0) {
src_top_edge -= 4;
}
}
if (src_top_edge < MultiplyBy4(row4x4_start_) ||
src_left_edge < MultiplyBy4(column4x4_start_) ||
src_bottom_edge > MultiplyBy4(row4x4_end_) ||
src_right_edge > MultiplyBy4(column4x4_end_)) {
return false;
}
// sb_height_log2 = use_128x128_superblock ? log2(128) : log2(64)
const int sb_height_log2 =
6 + static_cast<int>(sequence_header_.use_128x128_superblock);
const int active_sb_row = MultiplyBy4(block.row4x4) >> sb_height_log2;
const int active_64x64_block_column = MultiplyBy4(block.column4x4) >> 6;
const int src_sb_row = (src_bottom_edge - 1) >> sb_height_log2;
const int src_64x64_block_column = (src_right_edge - 1) >> 6;
const int total_64x64_blocks_per_row =
((column4x4_end_ - column4x4_start_ - 1) >> 4) + 1;
const int active_64x64_block =
active_sb_row * total_64x64_blocks_per_row + active_64x64_block_column;
const int src_64x64_block =
src_sb_row * total_64x64_blocks_per_row + src_64x64_block_column;
if (src_64x64_block >= active_64x64_block - kIntraBlockCopyDelay64x64Blocks) {
return false;
}
// Wavefront constraint: use only top left area of frame for reference.
if (src_sb_row > active_sb_row) return false;
const int gradient =
1 + kIntraBlockCopyDelay64x64Blocks +
static_cast<int>(sequence_header_.use_128x128_superblock);
const int wavefront_offset = gradient * (active_sb_row - src_sb_row);
return src_64x64_block_column < active_64x64_block_column -
kIntraBlockCopyDelay64x64Blocks +
wavefront_offset;
}
bool Tile::AssignInterMv(const Block& block, bool is_compound) {
int min[2];
int max[2];
GetClampParameters(block, min, max);
BlockParameters& bp = *block.bp;
const PredictionParameters& prediction_parameters = *bp.prediction_parameters;
if (is_compound) {
for (int i = 0; i < 2; ++i) {
const PredictionMode mode = GetSinglePredictionMode(i, bp.y_mode);
MotionVector predicted_mv;
if (mode == kPredictionModeGlobalMv) {
predicted_mv = prediction_parameters.global_mv[i];
} else {
const int ref_mv_index = (mode == kPredictionModeNearestMv ||
(mode == kPredictionModeNewMv &&
prediction_parameters.ref_mv_count <= 1))
? 0
: prediction_parameters.ref_mv_index;
predicted_mv = prediction_parameters.reference_mv(ref_mv_index, i);
if (ref_mv_index < prediction_parameters.ref_mv_count) {
predicted_mv.mv[0] = Clip3(predicted_mv.mv[0], min[0], max[0]);
predicted_mv.mv[1] = Clip3(predicted_mv.mv[1], min[1], max[1]);
}
}
if (mode == kPredictionModeNewMv) {
ReadMotionVector(block, i);
bp.mv.mv[i].mv[0] += predicted_mv.mv[0];
bp.mv.mv[i].mv[1] += predicted_mv.mv[1];
} else {
bp.mv.mv[i] = predicted_mv;
}
}
} else {
const PredictionMode mode = GetSinglePredictionMode(0, bp.y_mode);
MotionVector predicted_mv;
if (mode == kPredictionModeGlobalMv) {
predicted_mv = prediction_parameters.global_mv[0];
} else {
const int ref_mv_index = (mode == kPredictionModeNearestMv ||
(mode == kPredictionModeNewMv &&
prediction_parameters.ref_mv_count <= 1))
? 0
: prediction_parameters.ref_mv_index;
predicted_mv = prediction_parameters.reference_mv(ref_mv_index);
if (ref_mv_index < prediction_parameters.ref_mv_count) {
predicted_mv.mv[0] = Clip3(predicted_mv.mv[0], min[0], max[0]);
predicted_mv.mv[1] = Clip3(predicted_mv.mv[1], min[1], max[1]);
}
}
if (mode == kPredictionModeNewMv) {
ReadMotionVector(block, 0);
bp.mv.mv[0].mv[0] += predicted_mv.mv[0];
bp.mv.mv[0].mv[1] += predicted_mv.mv[1];
} else {
bp.mv.mv[0] = predicted_mv;
}
}
return IsMvValid(block, is_compound);
}
bool Tile::AssignIntraMv(const Block& block) {
// TODO(linfengz): Check if the clamping process is necessary.
int min[2];
int max[2];
GetClampParameters(block, min, max);
BlockParameters& bp = *block.bp;
const PredictionParameters& prediction_parameters = *bp.prediction_parameters;
const MotionVector& ref_mv_0 = prediction_parameters.reference_mv(0);
ReadMotionVector(block, 0);
if (ref_mv_0.mv32 == 0) {
const MotionVector& ref_mv_1 = prediction_parameters.reference_mv(1);
if (ref_mv_1.mv32 == 0) {
const int super_block_size4x4 = kNum4x4BlocksHigh[SuperBlockSize()];
if (block.row4x4 - super_block_size4x4 < row4x4_start_) {
bp.mv.mv[0].mv[1] -= MultiplyBy32(super_block_size4x4);
bp.mv.mv[0].mv[1] -= MultiplyBy8(kIntraBlockCopyDelayPixels);
} else {
bp.mv.mv[0].mv[0] -= MultiplyBy32(super_block_size4x4);
}
} else {
bp.mv.mv[0].mv[0] += Clip3(ref_mv_1.mv[0], min[0], max[0]);
bp.mv.mv[0].mv[1] += Clip3(ref_mv_1.mv[1], min[0], max[0]);
}
} else {
bp.mv.mv[0].mv[0] += Clip3(ref_mv_0.mv[0], min[0], max[0]);
bp.mv.mv[0].mv[1] += Clip3(ref_mv_0.mv[1], min[1], max[1]);
}
return IsMvValid(block, /*is_compound=*/false);
}
void Tile::ResetEntropyContext(const Block& block) {
for (int plane = 0; plane < (block.HasChroma() ? PlaneCount() : 1); ++plane) {
const int subsampling_x = subsampling_x_[plane];
const int start_x = block.column4x4 >> subsampling_x;
const int end_x =
std::min((block.column4x4 + block.width4x4) >> subsampling_x,
frame_header_.columns4x4);
memset(&coefficient_levels_[kEntropyContextTop][plane][start_x], 0,
end_x - start_x);
memset(&dc_categories_[kEntropyContextTop][plane][start_x], 0,
end_x - start_x);
const int subsampling_y = subsampling_y_[plane];
const int start_y = block.row4x4 >> subsampling_y;
const int end_y =
std::min((block.row4x4 + block.height4x4) >> subsampling_y,
frame_header_.rows4x4);
memset(&coefficient_levels_[kEntropyContextLeft][plane][start_y], 0,
end_y - start_y);
memset(&dc_categories_[kEntropyContextLeft][plane][start_y], 0,
end_y - start_y);
}
}
bool Tile::ComputePrediction(const Block& block) {
const BlockParameters& bp = *block.bp;
if (!bp.is_inter) return true;
const int mask =
(1 << (4 + static_cast<int>(sequence_header_.use_128x128_superblock))) -
1;
const int sub_block_row4x4 = block.row4x4 & mask;
const int sub_block_column4x4 = block.column4x4 & mask;
const int plane_count = block.HasChroma() ? PlaneCount() : 1;
// Returns true if this block applies local warping. The state is determined
// in the Y plane and carried for use in the U/V planes.
// But the U/V planes will not apply warping when the block size is smaller
// than 8x8, even if this variable is true.
bool is_local_valid = false;
// Local warping parameters, similar usage as is_local_valid.
GlobalMotion local_warp_params;
int plane = 0;
do {
const int8_t subsampling_x = subsampling_x_[plane];
const int8_t subsampling_y = subsampling_y_[plane];
const BlockSize plane_size = block.residual_size[plane];
const int block_width4x4 = kNum4x4BlocksWide[plane_size];
const int block_height4x4 = kNum4x4BlocksHigh[plane_size];
const int block_width = MultiplyBy4(block_width4x4);
const int block_height = MultiplyBy4(block_height4x4);
const int base_x = MultiplyBy4(block.column4x4 >> subsampling_x);
const int base_y = MultiplyBy4(block.row4x4 >> subsampling_y);
if (bp.reference_frame[1] == kReferenceFrameIntra) {
const int tr_row4x4 = sub_block_row4x4 >> subsampling_y;
const int tr_column4x4 =
(sub_block_column4x4 >> subsampling_x) + block_width4x4 + 1;
const int bl_row4x4 =
(sub_block_row4x4 >> subsampling_y) + block_height4x4;
const int bl_column4x4 = (sub_block_column4x4 >> subsampling_x) + 1;
const TransformSize tx_size =
k4x4SizeToTransformSize[k4x4WidthLog2[plane_size]]
[k4x4HeightLog2[plane_size]];
const bool has_left = block.left_available[plane];
const bool has_top = block.top_available[plane];
CALL_BITDEPTH_FUNCTION(
IntraPrediction, block, static_cast<Plane>(plane), base_x, base_y,
has_left, has_top,
block.scratch_buffer->block_decoded[plane][tr_row4x4][tr_column4x4],
block.scratch_buffer->block_decoded[plane][bl_row4x4][bl_column4x4],
kInterIntraToIntraMode[block.bp->prediction_parameters
->inter_intra_mode],
tx_size);
}
int candidate_row = block.row4x4;
int candidate_column = block.column4x4;
bool some_use_intra = bp.reference_frame[0] == kReferenceFrameIntra;
if (!some_use_intra && plane != 0) {
candidate_row = (candidate_row >> subsampling_y) << subsampling_y;
candidate_column = (candidate_column >> subsampling_x) << subsampling_x;
if (candidate_row != block.row4x4) {
// Top block.
const BlockParameters& bp_top =
*block_parameters_holder_.Find(candidate_row, block.column4x4);
some_use_intra = bp_top.reference_frame[0] == kReferenceFrameIntra;
if (!some_use_intra && candidate_column != block.column4x4) {
// Top-left block.
const BlockParameters& bp_top_left =
*block_parameters_holder_.Find(candidate_row, candidate_column);
some_use_intra =
bp_top_left.reference_frame[0] == kReferenceFrameIntra;
}
}
if (!some_use_intra && candidate_column != block.column4x4) {
// Left block.
const BlockParameters& bp_left =
*block_parameters_holder_.Find(block.row4x4, candidate_column);
some_use_intra = bp_left.reference_frame[0] == kReferenceFrameIntra;
}
}
int prediction_width;
int prediction_height;
if (some_use_intra) {
candidate_row = block.row4x4;
candidate_column = block.column4x4;
prediction_width = block_width;
prediction_height = block_height;
} else {
prediction_width = block.width >> subsampling_x;
prediction_height = block.height >> subsampling_y;
}
int r = 0;
int y = 0;
do {
int c = 0;
int x = 0;
do {
if (!InterPrediction(block, static_cast<Plane>(plane), base_x + x,
base_y + y, prediction_width, prediction_height,
candidate_row + r, candidate_column + c,
&is_local_valid, &local_warp_params)) {
return false;
}
++c;
x += prediction_width;
} while (x < block_width);
++r;
y += prediction_height;
} while (y < block_height);
} while (++plane < plane_count);
return true;
}
#undef CALL_BITDEPTH_FUNCTION
void Tile::PopulateDeblockFilterLevel(const Block& block) {
if (!post_filter_.DoDeblock()) return;
BlockParameters& bp = *block.bp;
const int mode_id =
static_cast<int>(kPredictionModeDeltasMask.Contains(bp.y_mode));
for (int i = 0; i < kFrameLfCount; ++i) {
if (delta_lf_all_zero_) {
bp.deblock_filter_level[i] = post_filter_.GetZeroDeltaDeblockFilterLevel(
bp.segment_id, i, bp.reference_frame[0], mode_id);
} else {
bp.deblock_filter_level[i] =
deblock_filter_levels_[bp.segment_id][i][bp.reference_frame[0]]
[mode_id];
}
}
}
bool Tile::ProcessBlock(int row4x4, int column4x4, BlockSize block_size,
ParameterTree* const tree,
TileScratchBuffer* const scratch_buffer,
ResidualPtr* residual) {
// Do not process the block if the starting point is beyond the visible frame.
// This is equivalent to the has_row/has_column check in the
// decode_partition() section of the spec when partition equals
// kPartitionHorizontal or kPartitionVertical.
if (row4x4 >= frame_header_.rows4x4 ||
column4x4 >= frame_header_.columns4x4) {
return true;
}
BlockParameters& bp = *tree->parameters();
block_parameters_holder_.FillCache(row4x4, column4x4, block_size, &bp);
Block block(*this, block_size, row4x4, column4x4, scratch_buffer, residual);
bp.size = block_size;
bp.prediction_parameters =
split_parse_and_decode_ ? std::unique_ptr<PredictionParameters>(
new (std::nothrow) PredictionParameters())
: std::move(prediction_parameters_);
if (bp.prediction_parameters == nullptr) return false;
if (!DecodeModeInfo(block)) return false;
bp.is_global_mv_block = (bp.y_mode == kPredictionModeGlobalMv ||
bp.y_mode == kPredictionModeGlobalGlobalMv) &&
!IsBlockDimension4(bp.size);
PopulateDeblockFilterLevel(block);
if (!ReadPaletteTokens(block)) return false;
DecodeTransformSize(block);
// Part of Section 5.11.37 in the spec (implemented as a simple lookup).
bp.uv_transform_size = frame_header_.segmentation.lossless[bp.segment_id]
? kTransformSize4x4
: kUVTransformSize[block.residual_size[kPlaneU]];
if (bp.skip) ResetEntropyContext(block);
if (split_parse_and_decode_) {
if (!Residual(block, kProcessingModeParseOnly)) return false;
} else {
if (!ComputePrediction(block) ||
!Residual(block, kProcessingModeParseAndDecode)) {
return false;
}
}
// If frame_header_.segmentation.enabled is false, bp.segment_id is 0 for all
// blocks. We don't need to call save bp.segment_id in the current frame
// because the current frame's segmentation map will be cleared to all 0s.
//
// If frame_header_.segmentation.enabled is true and
// frame_header_.segmentation.update_map is false, we will copy the previous
// frame's segmentation map to the current frame. So we don't need to call
// save bp.segment_id in the current frame.
if (frame_header_.segmentation.enabled &&
frame_header_.segmentation.update_map) {
const int x_limit = std::min(frame_header_.columns4x4 - column4x4,
static_cast<int>(block.width4x4));
const int y_limit = std::min(frame_header_.rows4x4 - row4x4,
static_cast<int>(block.height4x4));
current_frame_.segmentation_map()->FillBlock(row4x4, column4x4, x_limit,
y_limit, bp.segment_id);
}
StoreMotionFieldMvsIntoCurrentFrame(block);
if (!split_parse_and_decode_) {
prediction_parameters_ = std::move(bp.prediction_parameters);
}
return true;
}
bool Tile::DecodeBlock(ParameterTree* const tree,
TileScratchBuffer* const scratch_buffer,
ResidualPtr* residual) {
const int row4x4 = tree->row4x4();
const int column4x4 = tree->column4x4();
if (row4x4 >= frame_header_.rows4x4 ||
column4x4 >= frame_header_.columns4x4) {
return true;
}
const BlockSize block_size = tree->block_size();
Block block(*this, block_size, row4x4, column4x4, scratch_buffer, residual);
if (!ComputePrediction(block) ||
!Residual(block, kProcessingModeDecodeOnly)) {
return false;
}
block.bp->prediction_parameters.reset(nullptr);
return true;
}
bool Tile::ProcessPartition(int row4x4_start, int column4x4_start,
ParameterTree* const root,
TileScratchBuffer* const scratch_buffer,
ResidualPtr* residual) {
Stack<ParameterTree*, kDfsStackSize> stack;
// Set up the first iteration.
ParameterTree* node = root;
int row4x4 = row4x4_start;
int column4x4 = column4x4_start;
BlockSize block_size = SuperBlockSize();
// DFS loop. If it sees a terminal node (leaf node), ProcessBlock is invoked.
// Otherwise, the children are pushed into the stack for future processing.
do {
if (!stack.Empty()) {
// Set up subsequent iterations.
node = stack.Pop();
row4x4 = node->row4x4();
column4x4 = node->column4x4();
block_size = node->block_size();
}
if (row4x4 >= frame_header_.rows4x4 ||
column4x4 >= frame_header_.columns4x4) {
continue;
}
const int block_width4x4 = kNum4x4BlocksWide[block_size];
assert(block_width4x4 == kNum4x4BlocksHigh[block_size]);
const int half_block4x4 = block_width4x4 >> 1;
const bool has_rows = (row4x4 + half_block4x4) < frame_header_.rows4x4;
const bool has_columns =
(column4x4 + half_block4x4) < frame_header_.columns4x4;
Partition partition;
if (!ReadPartition(row4x4, column4x4, block_size, has_rows, has_columns,
&partition)) {
LIBGAV1_DLOG(ERROR, "Failed to read partition for row: %d column: %d",
row4x4, column4x4);
return false;
}
const BlockSize sub_size = kSubSize[partition][block_size];
// Section 6.10.4: It is a requirement of bitstream conformance that
// get_plane_residual_size( subSize, 1 ) is not equal to BLOCK_INVALID
// every time subSize is computed.
if (sub_size == kBlockInvalid ||
kPlaneResidualSize[sub_size]
[sequence_header_.color_config.subsampling_x]
[sequence_header_.color_config.subsampling_y] ==
kBlockInvalid) {
LIBGAV1_DLOG(
ERROR,
"Invalid sub-block/plane size for row: %d column: %d partition: "
"%d block_size: %d sub_size: %d subsampling_x/y: %d, %d",
row4x4, column4x4, partition, block_size, sub_size,
sequence_header_.color_config.subsampling_x,
sequence_header_.color_config.subsampling_y);
return false;
}
if (!node->SetPartitionType(partition)) {
LIBGAV1_DLOG(ERROR, "node->SetPartitionType() failed.");
return false;
}
switch (partition) {
case kPartitionNone:
if (!ProcessBlock(row4x4, column4x4, sub_size, node, scratch_buffer,
residual)) {
return false;
}
break;
case kPartitionSplit:
// The children must be added in reverse order since a stack is being
// used.
for (int i = 3; i >= 0; --i) {
ParameterTree* const child = node->children(i);
assert(child != nullptr);
stack.Push(child);
}
break;
case kPartitionHorizontal:
case kPartitionVertical:
case kPartitionHorizontalWithTopSplit:
case kPartitionHorizontalWithBottomSplit:
case kPartitionVerticalWithLeftSplit:
case kPartitionVerticalWithRightSplit:
case kPartitionHorizontal4:
case kPartitionVertical4:
for (int i = 0; i < 4; ++i) {
ParameterTree* const child = node->children(i);
// Once a null child is seen, all the subsequent children will also be
// null.
if (child == nullptr) break;
if (!ProcessBlock(child->row4x4(), child->column4x4(),
child->block_size(), child, scratch_buffer,
residual)) {
return false;
}
}
break;
}
} while (!stack.Empty());
return true;
}
void Tile::ResetLoopRestorationParams() {
for (int plane = kPlaneY; plane < kMaxPlanes; ++plane) {
for (int i = WienerInfo::kVertical; i <= WienerInfo::kHorizontal; ++i) {
reference_unit_info_[plane].sgr_proj_info.multiplier[i] =
kSgrProjDefaultMultiplier[i];
for (int j = 0; j < kNumWienerCoefficients; ++j) {
reference_unit_info_[plane].wiener_info.filter[i][j] =
kWienerDefaultFilter[j];
}
}
}
}
void Tile::ResetCdef(const int row4x4, const int column4x4) {
if (!sequence_header_.enable_cdef) return;
const int row = DivideBy16(row4x4);
const int column = DivideBy16(column4x4);
cdef_index_[row][column] = -1;
if (sequence_header_.use_128x128_superblock) {
const int cdef_size4x4 = kNum4x4BlocksWide[kBlock64x64];
const int border_row = DivideBy16(row4x4 + cdef_size4x4);
const int border_column = DivideBy16(column4x4 + cdef_size4x4);
cdef_index_[row][border_column] = -1;
cdef_index_[border_row][column] = -1;
cdef_index_[border_row][border_column] = -1;
}
}
void Tile::ClearBlockDecoded(TileScratchBuffer* const scratch_buffer,
int row4x4, int column4x4) {
// Set everything to false.
memset(scratch_buffer->block_decoded, 0,
sizeof(scratch_buffer->block_decoded));
// Set specific edge cases to true.
const int sb_size4 = sequence_header_.use_128x128_superblock ? 32 : 16;
for (int plane = 0; plane < PlaneCount(); ++plane) {
const int subsampling_x = subsampling_x_[plane];
const int subsampling_y = subsampling_y_[plane];
const int sb_width4 = (column4x4_end_ - column4x4) >> subsampling_x;
const int sb_height4 = (row4x4_end_ - row4x4) >> subsampling_y;
// The memset is equivalent to the following lines in the spec:
// for ( x = -1; x <= ( sbSize4 >> subX ); x++ ) {
// if ( y < 0 && x < sbWidth4 ) {
// BlockDecoded[plane][y][x] = 1
// }
// }
const int num_elements =
std::min((sb_size4 >> subsampling_x_[plane]) + 1, sb_width4) + 1;
memset(&scratch_buffer->block_decoded[plane][0][0], 1, num_elements);
// The for loop is equivalent to the following lines in the spec:
// for ( y = -1; y <= ( sbSize4 >> subY ); y++ )
// if ( x < 0 && y < sbHeight4 )
// BlockDecoded[plane][y][x] = 1
// }
// }
// BlockDecoded[plane][sbSize4 >> subY][-1] = 0
for (int y = -1; y < std::min((sb_size4 >> subsampling_y), sb_height4);
++y) {
scratch_buffer->block_decoded[plane][y + 1][0] = true;
}
}
}
bool Tile::ProcessSuperBlock(int row4x4, int column4x4, int block_width4x4,
TileScratchBuffer* const scratch_buffer,
ProcessingMode mode) {
const bool parsing =
mode == kProcessingModeParseOnly || mode == kProcessingModeParseAndDecode;
const bool decoding = mode == kProcessingModeDecodeOnly ||
mode == kProcessingModeParseAndDecode;
if (parsing) {
read_deltas_ = frame_header_.delta_q.present;
ResetCdef(row4x4, column4x4);
}
if (decoding) {
ClearBlockDecoded(scratch_buffer, row4x4, column4x4);
}
const BlockSize block_size = SuperBlockSize();
if (parsing) {
ReadLoopRestorationCoefficients(row4x4, column4x4, block_size);
}
const int row = row4x4 / block_width4x4;
const int column = column4x4 / block_width4x4;
if (parsing && decoding) {
uint8_t* residual_buffer = residual_buffer_.get();
if (!ProcessPartition(row4x4, column4x4,
block_parameters_holder_.Tree(row, column),
scratch_buffer, &residual_buffer)) {
LIBGAV1_DLOG(ERROR, "Error decoding partition row: %d column: %d", row4x4,
column4x4);
return false;
}
return true;
}
const int sb_row_index = SuperBlockRowIndex(row4x4);
const int sb_column_index = SuperBlockColumnIndex(column4x4);
if (parsing) {
residual_buffer_threaded_[sb_row_index][sb_column_index] =
residual_buffer_pool_->Get();
if (residual_buffer_threaded_[sb_row_index][sb_column_index] == nullptr) {
LIBGAV1_DLOG(ERROR, "Failed to get residual buffer.");
return false;
}
uint8_t* residual_buffer =
residual_buffer_threaded_[sb_row_index][sb_column_index]->buffer();
if (!ProcessPartition(row4x4, column4x4,
block_parameters_holder_.Tree(row, column),
scratch_buffer, &residual_buffer)) {
LIBGAV1_DLOG(ERROR, "Error parsing partition row: %d column: %d", row4x4,
column4x4);
return false;
}
} else {
uint8_t* residual_buffer =
residual_buffer_threaded_[sb_row_index][sb_column_index]->buffer();
if (!DecodeSuperBlock(block_parameters_holder_.Tree(row, column),
scratch_buffer, &residual_buffer)) {
LIBGAV1_DLOG(ERROR, "Error decoding superblock row: %d column: %d",
row4x4, column4x4);
return false;
}
residual_buffer_pool_->Release(
std::move(residual_buffer_threaded_[sb_row_index][sb_column_index]));
}
return true;
}
bool Tile::DecodeSuperBlock(ParameterTree* const tree,
TileScratchBuffer* const scratch_buffer,
ResidualPtr* residual) {
Stack<ParameterTree*, kDfsStackSize> stack;
stack.Push(tree);
do {
ParameterTree* const node = stack.Pop();
if (node->partition() != kPartitionNone) {
for (int i = 3; i >= 0; --i) {
if (node->children(i) == nullptr) continue;
stack.Push(node->children(i));
}
continue;
}
if (!DecodeBlock(node, scratch_buffer, residual)) {
LIBGAV1_DLOG(ERROR, "Error decoding block row: %d column: %d",
node->row4x4(), node->column4x4());
return false;
}
} while (!stack.Empty());
return true;
}
void Tile::ReadLoopRestorationCoefficients(int row4x4, int column4x4,
BlockSize block_size) {
if (frame_header_.allow_intrabc) return;
LoopRestorationInfo* const restoration_info = post_filter_.restoration_info();
const bool is_superres_scaled =
frame_header_.width != frame_header_.upscaled_width;
for (int plane = kPlaneY; plane < PlaneCount(); ++plane) {
LoopRestorationUnitInfo unit_info;
if (restoration_info->PopulateUnitInfoForSuperBlock(
static_cast<Plane>(plane), block_size, is_superres_scaled,
frame_header_.superres_scale_denominator, row4x4, column4x4,
&unit_info)) {
for (int unit_row = unit_info.row_start; unit_row < unit_info.row_end;
++unit_row) {
for (int unit_column = unit_info.column_start;
unit_column < unit_info.column_end; ++unit_column) {
const int unit_id = unit_row * restoration_info->num_horizontal_units(
static_cast<Plane>(plane)) +
unit_column;
restoration_info->ReadUnitCoefficients(
&reader_, &symbol_decoder_context_, static_cast<Plane>(plane),
unit_id, &reference_unit_info_);
}
}
}
}
}
void Tile::StoreMotionFieldMvsIntoCurrentFrame(const Block& block) {
if (frame_header_.refresh_frame_flags == 0 ||
IsIntraFrame(frame_header_.frame_type)) {
return;
}
// Iterate over odd rows/columns beginning at the first odd row/column for the
// block. It is done this way because motion field mvs are only needed at a
// 8x8 granularity.
const int row_start4x4 = block.row4x4 | 1;
const int row_limit4x4 =
std::min(block.row4x4 + block.height4x4, frame_header_.rows4x4);
if (row_start4x4 >= row_limit4x4) return;
const int column_start4x4 = block.column4x4 | 1;
const int column_limit4x4 =
std::min(block.column4x4 + block.width4x4, frame_header_.columns4x4);
if (column_start4x4 >= column_limit4x4) return;
// The largest reference MV component that can be saved.
constexpr int kRefMvsLimit = (1 << 12) - 1;
const BlockParameters& bp = *block.bp;
ReferenceInfo* reference_info = current_frame_.reference_info();
for (int i = 1; i >= 0; --i) {
const ReferenceFrameType reference_frame_to_store = bp.reference_frame[i];
// Must make a local copy so that StoreMotionFieldMvs() knows there is no
// overlap between load and store.
const MotionVector mv_to_store = bp.mv.mv[i];
const int mv_row = std::abs(mv_to_store.mv[MotionVector::kRow]);
const int mv_column = std::abs(mv_to_store.mv[MotionVector::kColumn]);
if (reference_frame_to_store > kReferenceFrameIntra &&
// kRefMvsLimit equals 0x07FF, so we can first bitwise OR the two
// absolute values and then compare with kRefMvsLimit to save a branch.
// The next line is equivalent to:
// mv_row <= kRefMvsLimit && mv_column <= kRefMvsLimit
(mv_row | mv_column) <= kRefMvsLimit &&
reference_info->relative_distance_from[reference_frame_to_store] < 0) {
const int row_start8x8 = DivideBy2(row_start4x4);
const int row_limit8x8 = DivideBy2(row_limit4x4);
const int column_start8x8 = DivideBy2(column_start4x4);
const int column_limit8x8 = DivideBy2(column_limit4x4);
const int rows = row_limit8x8 - row_start8x8;
const int columns = column_limit8x8 - column_start8x8;
const ptrdiff_t stride = DivideBy2(current_frame_.columns4x4());
ReferenceFrameType* const reference_frame_row_start =
&reference_info
->motion_field_reference_frame[row_start8x8][column_start8x8];
MotionVector* const mv =
&reference_info->motion_field_mv[row_start8x8][column_start8x8];
// Specialize columns cases 1, 2, 4, 8 and 16. This makes memset() inlined
// and simplifies std::fill() for these cases.
if (columns <= 1) {
// Don't change the above condition to (columns == 1).
// Condition (columns <= 1) may help the compiler simplify the inlining
// of the general case of StoreMotionFieldMvs() by eliminating the
// (columns == 0) case.
assert(columns == 1);
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
1, reference_frame_row_start, mv);
} else if (columns == 2) {
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
2, reference_frame_row_start, mv);
} else if (columns == 4) {
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
4, reference_frame_row_start, mv);
} else if (columns == 8) {
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
8, reference_frame_row_start, mv);
} else if (columns == 16) {
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
16, reference_frame_row_start, mv);
} else if (columns < 16) {
// This always true condition (columns < 16) may help the compiler
// simplify the inlining of the following function.
// This general case is rare and usually only happens to the blocks
// which contain the right boundary of the frame.
StoreMotionFieldMvs(reference_frame_to_store, mv_to_store, stride, rows,
columns, reference_frame_row_start, mv);
} else {
assert(false);
}
return;
}
}
}
} // namespace libgav1