| /* |
| * Copyright (c) 2023 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "common_video/h265/h265_pps_parser.h" |
| |
| #include <memory> |
| #include <vector> |
| |
| #include "absl/types/optional.h" |
| #include "common_video/h265/h265_common.h" |
| #include "rtc_base/bit_buffer.h" |
| #include "rtc_base/bitstream_reader.h" |
| #include "rtc_base/logging.h" |
| |
| #define IN_RANGE_OR_RETURN_NULL(val, min, max) \ |
| do { \ |
| if (!reader.Ok() || (val) < (min) || (val) > (max)) { \ |
| RTC_LOG(LS_WARNING) << "Error in stream: invalid value, expected " #val \ |
| " to be" \ |
| << " in range [" << (min) << ":" << (max) << "]" \ |
| << " found " << (val) << " instead"; \ |
| return absl::nullopt; \ |
| } \ |
| } while (0) |
| |
| #define IN_RANGE_OR_RETURN_FALSE(val, min, max) \ |
| do { \ |
| if (!reader.Ok() || (val) < (min) || (val) > (max)) { \ |
| RTC_LOG(LS_WARNING) << "Error in stream: invalid value, expected " #val \ |
| " to be" \ |
| << " in range [" << (min) << ":" << (max) << "]" \ |
| << " found " << (val) << " instead"; \ |
| return false; \ |
| } \ |
| } while (0) |
| |
| #define TRUE_OR_RETURN(a) \ |
| do { \ |
| if (!reader.Ok() || !(a)) { \ |
| RTC_LOG(LS_WARNING) << "Error in stream: invalid value, expected " \ |
| << #a; \ |
| return absl::nullopt; \ |
| } \ |
| } while (0) |
| |
| namespace { |
| constexpr int kMaxNumTileColumnWidth = 19; |
| constexpr int kMaxNumTileRowHeight = 21; |
| constexpr int kMaxRefIdxActive = 15; |
| } // namespace |
| |
| namespace webrtc { |
| |
| // General note: this is based off the 08/2021 version of the H.265 standard. |
| // You can find it on this page: |
| // http://www.itu.int/rec/T-REC-H.265 |
| |
| absl::optional<H265PpsParser::PpsState> H265PpsParser::ParsePps( |
| const uint8_t* data, |
| size_t length, |
| const H265SpsParser::SpsState* sps) { |
| // First, parse out rbsp, which is basically the source buffer minus emulation |
| // bytes (the last byte of a 0x00 0x00 0x03 sequence). RBSP is defined in |
| // section 7.3.1.1 of the H.265 standard. |
| return ParseInternal(H265::ParseRbsp(data, length), sps); |
| } |
| |
| bool H265PpsParser::ParsePpsIds(const uint8_t* data, |
| size_t length, |
| uint32_t* pps_id, |
| uint32_t* sps_id) { |
| RTC_DCHECK(pps_id); |
| RTC_DCHECK(sps_id); |
| // First, parse out rbsp, which is basically the source buffer minus emulation |
| // bytes (the last byte of a 0x00 0x00 0x03 sequence). RBSP is defined in |
| // section 7.3.1.1 of the H.265 standard. |
| std::vector<uint8_t> unpacked_buffer = H265::ParseRbsp(data, length); |
| BitstreamReader reader(unpacked_buffer); |
| *pps_id = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE(*pps_id, 0, 63); |
| *sps_id = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE(*sps_id, 0, 15); |
| return reader.Ok(); |
| } |
| |
| absl::optional<H265PpsParser::PpsState> H265PpsParser::ParseInternal( |
| rtc::ArrayView<const uint8_t> buffer, |
| const H265SpsParser::SpsState* sps) { |
| BitstreamReader reader(buffer); |
| PpsState pps; |
| |
| if (!sps) { |
| return absl::nullopt; |
| } |
| |
| if (!ParsePpsIdsInternal(reader, pps.pps_id, pps.sps_id)) { |
| return absl::nullopt; |
| } |
| |
| // dependent_slice_segments_enabled_flag: u(1) |
| pps.dependent_slice_segments_enabled_flag = reader.Read<bool>(); |
| // output_flag_present_flag: u(1) |
| pps.output_flag_present_flag = reader.Read<bool>(); |
| // num_extra_slice_header_bits: u(3) |
| pps.num_extra_slice_header_bits = reader.ReadBits(3); |
| IN_RANGE_OR_RETURN_NULL(pps.num_extra_slice_header_bits, 0, 2); |
| // sign_data_hiding_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // cabac_init_present_flag: u(1) |
| pps.cabac_init_present_flag = reader.Read<bool>(); |
| // num_ref_idx_l0_default_active_minus1: ue(v) |
| pps.num_ref_idx_l0_default_active_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps.num_ref_idx_l0_default_active_minus1, 0, |
| kMaxRefIdxActive - 1); |
| // num_ref_idx_l1_default_active_minus1: ue(v) |
| pps.num_ref_idx_l1_default_active_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps.num_ref_idx_l1_default_active_minus1, 0, |
| kMaxRefIdxActive - 1); |
| // init_qp_minus26: se(v) |
| pps.init_qp_minus26 = reader.ReadSignedExponentialGolomb(); |
| pps.qp_bd_offset_y = 6 * sps->bit_depth_luma_minus8; |
| // Sanity-check parsed value |
| IN_RANGE_OR_RETURN_NULL(pps.init_qp_minus26, -(26 + pps.qp_bd_offset_y), 25); |
| // constrained_intra_pred_flag: u(1)log2_min_pcm_luma_coding_block_size_minus3 |
| reader.ConsumeBits(1); |
| // transform_skip_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // cu_qp_delta_enabled_flag: u(1) |
| bool cu_qp_delta_enabled_flag = reader.Read<bool>(); |
| if (cu_qp_delta_enabled_flag) { |
| // diff_cu_qp_delta_depth: ue(v) |
| uint32_t diff_cu_qp_delta_depth = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(diff_cu_qp_delta_depth, 0, |
| sps->log2_diff_max_min_luma_coding_block_size); |
| } |
| // pps_cb_qp_offset: se(v) |
| int32_t pps_cb_qp_offset = reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps_cb_qp_offset, -12, 12); |
| // pps_cr_qp_offset: se(v) |
| int32_t pps_cr_qp_offset = reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps_cr_qp_offset, -12, 12); |
| // pps_slice_chroma_qp_offsets_present_flag: u(1) |
| reader.ConsumeBits(1); |
| // weighted_pred_flag: u(1) |
| pps.weighted_pred_flag = reader.Read<bool>(); |
| // weighted_bipred_flag: u(1) |
| pps.weighted_bipred_flag = reader.Read<bool>(); |
| // transquant_bypass_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // tiles_enabled_flag: u(1) |
| bool tiles_enabled_flag = reader.Read<bool>(); |
| // entropy_coding_sync_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| if (tiles_enabled_flag) { |
| // num_tile_columns_minus1: ue(v) |
| uint32_t num_tile_columns_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(num_tile_columns_minus1, 0, |
| sps->pic_width_in_ctbs_y - 1); |
| TRUE_OR_RETURN(num_tile_columns_minus1 < kMaxNumTileColumnWidth); |
| // num_tile_rows_minus1: ue(v) |
| uint32_t num_tile_rows_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(num_tile_rows_minus1, 0, |
| sps->pic_height_in_ctbs_y - 1); |
| TRUE_OR_RETURN((num_tile_columns_minus1 != 0) || |
| (num_tile_rows_minus1 != 0)); |
| TRUE_OR_RETURN(num_tile_rows_minus1 < kMaxNumTileRowHeight); |
| // uniform_spacing_flag: u(1) |
| bool uniform_spacing_flag = reader.Read<bool>(); |
| if (!uniform_spacing_flag) { |
| int column_width_minus1[kMaxNumTileColumnWidth]; |
| column_width_minus1[num_tile_columns_minus1] = |
| sps->pic_width_in_ctbs_y - 1; |
| for (uint32_t i = 0; i < num_tile_columns_minus1; i++) { |
| // column_width_minus1: ue(v) |
| column_width_minus1[i] = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL( |
| column_width_minus1[i], 0, |
| column_width_minus1[num_tile_columns_minus1] - 1); |
| column_width_minus1[num_tile_columns_minus1] -= |
| column_width_minus1[i] + 1; |
| } |
| int row_height_minus1[kMaxNumTileRowHeight]; |
| row_height_minus1[num_tile_rows_minus1] = sps->pic_height_in_ctbs_y - 1; |
| for (uint32_t i = 0; i < num_tile_rows_minus1; i++) { |
| // row_height_minus1: ue(v) |
| row_height_minus1[i] = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(row_height_minus1[i], 0, |
| row_height_minus1[num_tile_rows_minus1] - 1); |
| row_height_minus1[num_tile_rows_minus1] -= row_height_minus1[i] + 1; |
| } |
| // loop_filter_across_tiles_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| } |
| } |
| // pps_loop_filter_across_slices_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // deblocking_filter_control_present_flag: u(1) |
| bool deblocking_filter_control_present_flag = reader.Read<bool>(); |
| if (deblocking_filter_control_present_flag) { |
| // deblocking_filter_override_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // pps_deblocking_filter_disabled_flag: u(1) |
| bool pps_deblocking_filter_disabled_flag = reader.Read<bool>(); |
| if (!pps_deblocking_filter_disabled_flag) { |
| // pps_beta_offset_div2: se(v) |
| int pps_beta_offset_div2 = reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps_beta_offset_div2, -6, 6); |
| // pps_tc_offset_div2: se(v) |
| int pps_tc_offset_div2 = reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(pps_tc_offset_div2, -6, 6); |
| } |
| } |
| // pps_scaling_list_data_present_flag: u(1) |
| bool pps_scaling_list_data_present_flag = 0; |
| pps_scaling_list_data_present_flag = reader.Read<bool>(); |
| if (pps_scaling_list_data_present_flag) { |
| // scaling_list_data() |
| if (!H265SpsParser::ParseScalingListData(reader)) { |
| return absl::nullopt; |
| } |
| } |
| // lists_modification_present_flag: u(1) |
| pps.lists_modification_present_flag = reader.Read<bool>(); |
| |
| if (!reader.Ok()) { |
| return absl::nullopt; |
| } |
| |
| return pps; |
| } |
| |
| bool H265PpsParser::ParsePpsIdsInternal(BitstreamReader& reader, |
| uint32_t& pps_id, |
| uint32_t& sps_id) { |
| // pic_parameter_set_id: ue(v) |
| pps_id = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE(pps_id, 0, 63); |
| // seq_parameter_set_id: ue(v) |
| sps_id = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE(sps_id, 0, 15); |
| return true; |
| } |
| |
| } // namespace webrtc |
