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Diffstat (limited to 'src/tile/tile.cc')
| -rw-r--r-- | src/tile/tile.cc | 2573 |
1 files changed, 2573 insertions, 0 deletions
diff --git a/src/tile/tile.cc b/src/tile/tile.cc new file mode 100644 index 0000000..ee48f17 --- /dev/null +++ b/src/tile/tile.cc @@ -0,0 +1,2573 @@ +// 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/scan_tables.inc" + +// 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, + const QuantizerMatrix& quantizer_matrix, + 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), + quantizer_matrix_(quantizer_matrix), + 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 = kPlaneY; 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 = + SubsampledValue(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 = + SubsampledValue(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 = kPlaneY; 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]; + switch (tx_set) { + case kTransformSetInter1: + tx_type = static_cast<TransformType>(reader_.ReadSymbol<16>(cdf)); + break; + case kTransformSetInter2: + tx_type = static_cast<TransformType>(reader_.ReadSymbol<12>(cdf)); + break; + default: + assert(tx_set == kTransformSetInter3); + tx_type = static_cast<TransformType>(reader_.ReadSymbol(cdf)); + break; + } + } 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]; + assert(tx_set == kTransformSetIntra1 || tx_set == kTransformSetIntra2); + tx_type = static_cast<TransformType>((tx_set == kTransformSetIntra1) + ? reader_.ReadSymbol<7>(cdf) + : reader_.ReadSymbol<5>(cdf)); + } + + // 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, TransformSize tx_size, int adjusted_tx_width_log2, + int eob, + uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1], + uint16_t coeff_base_range_cdf[kCoeffBaseRangeContexts] + [kCoeffBaseRangeSymbolCount + 1], + ResidualType* const quantized_buffer, uint8_t* const level_buffer) { + const int tx_width = 1 << adjusted_tx_width_log2; + for (int i = eob - 2; i >= 1; --i) { + 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]; + auto* const levels = &level_buffer[pos]; + const int neighbor_sum = 1 + levels[1] + levels[tx_width] + + levels[tx_width + 1] + levels[2] + + levels[MultiplyBy2(tx_width)]; + const int context = + ((neighbor_sum > 7) ? 4 : DivideBy2(neighbor_sum)) + + kCoeffBaseContextOffset[tx_size][std::min(row, 4)][std::min(column, 4)]; + int level = + reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]); + levels[0] = level; + 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[1] + // {0, 1} + quantized[tx_width] + // {1, 0} + quantized[tx_width + 1])); // {1, 1} + context += 14 >> static_cast<int>((row | column) < 2); + level += ReadCoeffBaseRange(coeff_base_range_cdf[context]); + } + quantized[0] = level; + } + // Read position 0. + { + auto* const quantized = &quantized_buffer[0]; + int level = reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[0]); + level_buffer[0] = level; + 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. + const int context = + std::min(6, DivideBy2(1 + quantized[1] + // {0, 1} + quantized[tx_width] + // {1, 0} + quantized[tx_width + 1])); // {1, 1} + level += ReadCoeffBaseRange(coeff_base_range_cdf[context]); + } + quantized[0] = level; + } +} + +// 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, TransformSize /*tx_size*/, int adjusted_tx_width_log2, + int eob, + uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1], + uint16_t coeff_base_range_cdf[kCoeffBaseRangeContexts] + [kCoeffBaseRangeSymbolCount + 1], + ResidualType* const quantized_buffer, uint8_t* const level_buffer) { + const int tx_width = 1 << adjusted_tx_width_log2; + int i = eob - 2; + do { + const uint16_t pos = scan[i]; + const int column = pos & (tx_width - 1); + auto* const quantized = &quantized_buffer[pos]; + auto* const levels = &level_buffer[pos]; + const int neighbor_sum = + 1 + (levels[1] + // {0, 1} + levels[tx_width] + // {1, 0} + levels[2] + // {0, 2} + levels[3] + // {0, 3} + ((column + 4 < tx_width) ? levels[4] : 0)); // {0, 4} + const int context = ((neighbor_sum > 7) ? 4 : DivideBy2(neighbor_sum)) + + kCoeffBasePositionContextOffset[column]; + int level = + reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]); + levels[0] = level; + 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[1] + // {0, 1} + quantized[tx_width] + // {1, 0} + quantized[2])); // {0, 2} + if (pos != 0) { + context += 14 >> static_cast<int>(column == 0); + } + level += ReadCoeffBaseRange(coeff_base_range_cdf[context]); + } + 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, TransformSize /*tx_size*/, int adjusted_tx_width_log2, + int eob, + uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1], + uint16_t coeff_base_range_cdf[kCoeffBaseRangeContexts] + [kCoeffBaseRangeSymbolCount + 1], + ResidualType* const quantized_buffer, uint8_t* const level_buffer) { + const int tx_width = 1 << adjusted_tx_width_log2; + int i = eob - 2; + do { + 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]; + auto* const levels = &level_buffer[pos]; + const int neighbor_sum = + 1 + (((column + 1 < tx_width) ? levels[1] : 0) + // {0, 1} + levels[tx_width] + // {1, 0} + levels[MultiplyBy2(tx_width)] + // {2, 0} + levels[tx_width * 3] + // {3, 0} + levels[MultiplyBy4(tx_width)]); // {4, 0} + const int context = ((neighbor_sum > 7) ? 4 : DivideBy2(neighbor_sum)) + + kCoeffBasePositionContextOffset[row]; + int level = + reader_.ReadSymbol<kCoeffBaseSymbolCount>(coeff_base_cdf[context]); + levels[0] = level; + 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. + const int quantized_column1 = (column + 1 < tx_width) ? quantized[1] : 0; + 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(coeff_base_range_cdf[context]); + } + 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); +} + +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(uint16_t* cdf) { + int level = 0; + for (int j = 0; j < kCoeffBaseRangeMaxIterations; ++j) { + const int coeff_base_range = + reader_.ReadSymbol<kCoeffBaseRangeSymbolCount>(cdf); + 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_); + uint8_t level_buffer[(32 + kResidualPaddingVertical) * 32]; + memset( + level_buffer, 0, + kTransformWidth[adjusted_tx_size] * kTransformHeight[adjusted_tx_size] + + tx_padding); + 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); + int eob_pt = 1; + switch (eob_multi_size) { + case 0: + eob_pt += reader_.ReadSymbol<kEobPt16SymbolCount>( + symbol_decoder_context_.eob_pt_16_cdf[plane_type][context]); + break; + case 1: + eob_pt += reader_.ReadSymbol<kEobPt32SymbolCount>( + symbol_decoder_context_.eob_pt_32_cdf[plane_type][context]); + break; + case 2: + eob_pt += reader_.ReadSymbol<kEobPt64SymbolCount>( + symbol_decoder_context_.eob_pt_64_cdf[plane_type][context]); + break; + case 3: + eob_pt += reader_.ReadSymbol<kEobPt128SymbolCount>( + symbol_decoder_context_.eob_pt_128_cdf[plane_type][context]); + break; + case 4: + eob_pt += reader_.ReadSymbol<kEobPt256SymbolCount>( + symbol_decoder_context_.eob_pt_256_cdf[plane_type][context]); + break; + case 5: + eob_pt += reader_.ReadSymbol<kEobPt512SymbolCount>( + symbol_decoder_context_.eob_pt_512_cdf[plane_type]); + break; + case 6: + default: + eob_pt += reader_.ReadSymbol<kEobPt1024SymbolCount>( + symbol_decoder_context_.eob_pt_1024_cdf[plane_type]); + break; + } + 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); + auto coeff_base_range_cdf = + symbol_decoder_context_ + .coeff_base_range_cdf[clamped_tx_size_context][plane_type]; + // Read the last coefficient. + { + context = GetCoeffBaseContextEob(tx_size, eob - 1); + const uint16_t pos = scan[eob - 1]; + int level = + 1 + reader_.ReadSymbol<kCoeffBaseEobSymbolCount>( + symbol_decoder_context_ + .coeff_base_eob_cdf[tx_size_context][plane_type][context]); + level_buffer[pos] = level; + if (level > kNumQuantizerBaseLevels) { + level += + ReadCoeffBaseRange(coeff_base_range_cdf[GetCoeffBaseRangeContextEob( + adjusted_tx_width_log2, pos, tx_class)]); + } + 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, TransformSize tx_size, int adjusted_tx_width_log2, + int eob, + uint16_t coeff_base_cdf[kCoeffBaseContexts][kCoeffBaseSymbolCount + 1], + uint16_t coeff_base_range_cdf[kCoeffBaseRangeContexts] + [kCoeffBaseRangeSymbolCount + 1], + ResidualType* quantized_buffer, + uint8_t* level_buffer) = {&Tile::ReadCoeffBase2D<ResidualType>, + &Tile::ReadCoeffBaseHorizontal<ResidualType>, + &Tile::ReadCoeffBaseVertical<ResidualType>}; + (this->*kGetCoeffBaseFunc[tx_class])( + scan, tx_size, adjusted_tx_width_log2, eob, + symbol_decoder_context_.coeff_base_cdf[tx_size_context][plane_type], + coeff_base_range_cdf, residual, level_buffer); + } + 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) + ? quantizer_matrix_[frame_header_.quantizer.matrix_level[plane]] + [plane_type][adjusted_tx_size] + .get() + : 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) { + const int num_planes = block.HasChroma() ? PlaneCount() : 1; + int plane = kPlaneY; + do { + 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; + } + } + } + } + } while (++plane < num_planes); + } + } + 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) { + const int num_planes = block.HasChroma() ? PlaneCount() : 1; + int plane = kPlaneY; + do { + 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); + } while (++plane < num_planes); +} + +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 = kPlaneY; + 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 = kPlaneY; 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 |