| /* |
| * 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_sps_parser.h" |
| |
| #include <algorithm> |
| #include <memory> |
| #include <vector> |
| |
| #include "common_video/h265/h265_common.h" |
| #include "rtc_base/bit_buffer.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 { |
| using OptionalSps = absl::optional<webrtc::H265SpsParser::SpsState>; |
| using OptionalShortTermRefPicSet = |
| absl::optional<webrtc::H265SpsParser::ShortTermRefPicSet>; |
| using OptionalProfileTierLevel = |
| absl::optional<webrtc::H265SpsParser::ProfileTierLevel>; |
| |
| constexpr int kMaxNumSizeIds = 4; |
| constexpr int kMaxNumMatrixIds = 6; |
| constexpr int kMaxNumCoefs = 64; |
| } // namespace |
| |
| namespace webrtc { |
| |
| H265SpsParser::SpsState::SpsState() = default; |
| |
| H265SpsParser::ShortTermRefPicSet::ShortTermRefPicSet() = default; |
| |
| H265SpsParser::ProfileTierLevel::ProfileTierLevel() = default; |
| |
| int H265SpsParser::GetMaxLumaPs(int general_level_idc) { |
| // From Table A.8 - General tier and level limits. |
| // |general_level_idc| is 30x the actual level. |
| if (general_level_idc <= 30) // level 1 |
| return 36864; |
| if (general_level_idc <= 60) // level 2 |
| return 122880; |
| if (general_level_idc <= 63) // level 2.1 |
| return 245760; |
| if (general_level_idc <= 90) // level 3 |
| return 552960; |
| if (general_level_idc <= 93) // level 3.1 |
| return 983040; |
| if (general_level_idc <= 123) // level 4, 4.1 |
| return 2228224; |
| if (general_level_idc <= 156) // level 5, 5.1, 5.2 |
| return 8912896; |
| // level 6, 6.1, 6.2 - beyond that there's no actual limit. |
| return 35651584; |
| } |
| |
| size_t H265SpsParser::GetDpbMaxPicBuf(int general_profile_idc) { |
| // From A.4.2 - Profile-specific level limits for the video profiles. |
| // If sps_curr_pic_ref_enabled_flag is required to be zero, than this is 6 |
| // otherwise it is 7. |
| return (general_profile_idc >= kProfileIdcMain && |
| general_profile_idc <= kProfileIdcHighThroughput) |
| ? 6 |
| : 7; |
| } |
| |
| // 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 |
| |
| // Unpack RBSP and parse SPS state from the supplied buffer. |
| absl::optional<H265SpsParser::SpsState> H265SpsParser::ParseSps( |
| const uint8_t* data, |
| size_t length) { |
| RTC_DCHECK(data); |
| return ParseSpsInternal(H265::ParseRbsp(data, length)); |
| } |
| |
| bool H265SpsParser::ParseScalingListData(BitstreamReader& reader) { |
| uint32_t scaling_list_pred_mode_flag[kMaxNumSizeIds][kMaxNumMatrixIds]; |
| int scaling_list_pred_matrix_id_delta[kMaxNumSizeIds][kMaxNumMatrixIds]; |
| int32_t scaling_list_dc_coef_minus8[kMaxNumSizeIds][kMaxNumMatrixIds]; |
| int32_t scaling_list[kMaxNumSizeIds][kMaxNumMatrixIds][kMaxNumCoefs]; |
| for (int size_id = 0; size_id < kMaxNumSizeIds; size_id++) { |
| for (int matrix_id = 0; matrix_id < kMaxNumMatrixIds; |
| matrix_id += (size_id == 3) ? 3 : 1) { |
| // scaling_list_pred_mode_flag: u(1) |
| scaling_list_pred_mode_flag[size_id][matrix_id] = reader.Read<bool>(); |
| if (!scaling_list_pred_mode_flag[size_id][matrix_id]) { |
| // scaling_list_pred_matrix_id_delta: ue(v) |
| scaling_list_pred_matrix_id_delta[size_id][matrix_id] = |
| reader.ReadExponentialGolomb(); |
| if (size_id <= 2) { |
| IN_RANGE_OR_RETURN_FALSE( |
| scaling_list_pred_matrix_id_delta[size_id][matrix_id], 0, |
| matrix_id); |
| } else { // size_id == 3 |
| IN_RANGE_OR_RETURN_FALSE( |
| scaling_list_pred_matrix_id_delta[size_id][matrix_id], 0, |
| matrix_id / 3); |
| } |
| } else { |
| int32_t next_coef = 8; |
| uint32_t coef_num = std::min(kMaxNumCoefs, 1 << (4 + (size_id << 1))); |
| if (size_id > 1) { |
| // scaling_list_dc_coef_minus8: se(v) |
| scaling_list_dc_coef_minus8[size_id - 2][matrix_id] = |
| reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE( |
| scaling_list_dc_coef_minus8[size_id - 2][matrix_id], -7, 247); |
| next_coef = scaling_list_dc_coef_minus8[size_id - 2][matrix_id] + 8; |
| } |
| for (uint32_t i = 0; i < coef_num; i++) { |
| // scaling_list_delta_coef: se(v) |
| int32_t scaling_list_delta_coef = |
| reader.ReadSignedExponentialGolomb(); |
| IN_RANGE_OR_RETURN_FALSE(scaling_list_delta_coef, -128, 127); |
| next_coef = (next_coef + scaling_list_delta_coef + 256) % 256; |
| scaling_list[size_id][matrix_id][i] = next_coef; |
| } |
| } |
| } |
| } |
| return reader.Ok(); |
| } |
| |
| absl::optional<H265SpsParser::ShortTermRefPicSet> |
| H265SpsParser::ParseShortTermRefPicSet( |
| uint32_t st_rps_idx, |
| uint32_t num_short_term_ref_pic_sets, |
| const std::vector<H265SpsParser::ShortTermRefPicSet>& |
| short_term_ref_pic_set, |
| uint32_t sps_max_dec_pic_buffering_minus1, |
| BitstreamReader& reader) { |
| H265SpsParser::ShortTermRefPicSet st_ref_pic_set; |
| |
| bool inter_ref_pic_set_prediction_flag = false; |
| if (st_rps_idx != 0) { |
| // inter_ref_pic_set_prediction_flag: u(1) |
| inter_ref_pic_set_prediction_flag = reader.Read<bool>(); |
| } |
| |
| if (inter_ref_pic_set_prediction_flag) { |
| uint32_t delta_idx_minus1 = 0; |
| if (st_rps_idx == num_short_term_ref_pic_sets) { |
| // delta_idx_minus1: ue(v) |
| delta_idx_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(delta_idx_minus1, 0, st_rps_idx - 1); |
| } |
| // delta_rps_sign: u(1) |
| int delta_rps_sign = reader.ReadBits(1); |
| // abs_delta_rps_minus1: ue(v) |
| int abs_delta_rps_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(abs_delta_rps_minus1, 0, 0x7FFF); |
| int delta_rps = (1 - 2 * delta_rps_sign) * (abs_delta_rps_minus1 + 1); |
| uint32_t ref_rps_idx = st_rps_idx - (delta_idx_minus1 + 1); |
| uint32_t num_delta_pocs = |
| short_term_ref_pic_set[ref_rps_idx].num_delta_pocs; |
| RTC_CHECK_LT(num_delta_pocs, kMaxShortTermRefPicSets); |
| const ShortTermRefPicSet& ref_set = short_term_ref_pic_set[ref_rps_idx]; |
| bool used_by_curr_pic_flag[kMaxShortTermRefPicSets]; |
| bool use_delta_flag[kMaxShortTermRefPicSets]; |
| // 7.4.8 - use_delta_flag defaults to 1 if not present. |
| std::fill_n(use_delta_flag, kMaxShortTermRefPicSets, true); |
| |
| for (uint32_t j = 0; j <= num_delta_pocs; j++) { |
| // used_by_curr_pic_flag: u(1) |
| used_by_curr_pic_flag[j] = reader.Read<bool>(); |
| if (!used_by_curr_pic_flag[j]) { |
| // use_delta_flag: u(1) |
| use_delta_flag[j] = reader.Read<bool>(); |
| } |
| } |
| |
| // Calculate delta_poc_s{0,1}, used_by_curr_pic_s{0,1}, num_negative_pics |
| // and num_positive_pics. |
| // Equation 7-61 |
| int i = 0; |
| RTC_CHECK_LE(ref_set.num_negative_pics + ref_set.num_positive_pics, |
| kMaxShortTermRefPicSets); |
| for (int j = ref_set.num_positive_pics - 1; j >= 0; --j) { |
| int d_poc = ref_set.delta_poc_s1[j] + delta_rps; |
| if (d_poc < 0 && use_delta_flag[ref_set.num_negative_pics + j]) { |
| st_ref_pic_set.delta_poc_s0[i] = d_poc; |
| st_ref_pic_set.used_by_curr_pic_s0[i++] = |
| used_by_curr_pic_flag[ref_set.num_negative_pics + j]; |
| } |
| } |
| if (delta_rps < 0 && use_delta_flag[ref_set.num_delta_pocs]) { |
| st_ref_pic_set.delta_poc_s0[i] = delta_rps; |
| st_ref_pic_set.used_by_curr_pic_s0[i++] = |
| used_by_curr_pic_flag[ref_set.num_delta_pocs]; |
| } |
| for (uint32_t j = 0; j < ref_set.num_negative_pics; ++j) { |
| int d_poc = ref_set.delta_poc_s0[j] + delta_rps; |
| if (d_poc < 0 && use_delta_flag[j]) { |
| st_ref_pic_set.delta_poc_s0[i] = d_poc; |
| st_ref_pic_set.used_by_curr_pic_s0[i++] = used_by_curr_pic_flag[j]; |
| } |
| } |
| st_ref_pic_set.num_negative_pics = i; |
| // Equation 7-62 |
| i = 0; |
| for (int j = ref_set.num_negative_pics - 1; j >= 0; --j) { |
| int d_poc = ref_set.delta_poc_s0[j] + delta_rps; |
| if (d_poc > 0 && use_delta_flag[j]) { |
| st_ref_pic_set.delta_poc_s1[i] = d_poc; |
| st_ref_pic_set.used_by_curr_pic_s1[i++] = used_by_curr_pic_flag[j]; |
| } |
| } |
| if (delta_rps > 0 && use_delta_flag[ref_set.num_delta_pocs]) { |
| st_ref_pic_set.delta_poc_s1[i] = delta_rps; |
| st_ref_pic_set.used_by_curr_pic_s1[i++] = |
| used_by_curr_pic_flag[ref_set.num_delta_pocs]; |
| } |
| for (uint32_t j = 0; j < ref_set.num_positive_pics; ++j) { |
| int d_poc = ref_set.delta_poc_s1[j] + delta_rps; |
| if (d_poc > 0 && use_delta_flag[ref_set.num_negative_pics + j]) { |
| st_ref_pic_set.delta_poc_s1[i] = d_poc; |
| st_ref_pic_set.used_by_curr_pic_s1[i++] = |
| used_by_curr_pic_flag[ref_set.num_negative_pics + j]; |
| } |
| } |
| st_ref_pic_set.num_positive_pics = i; |
| |
| } else { |
| // num_negative_pics: ue(v) |
| st_ref_pic_set.num_negative_pics = reader.ReadExponentialGolomb(); |
| // num_positive_pics: ue(v) |
| st_ref_pic_set.num_positive_pics = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(st_ref_pic_set.num_negative_pics, 0, |
| sps_max_dec_pic_buffering_minus1); |
| IN_RANGE_OR_RETURN_NULL( |
| st_ref_pic_set.num_positive_pics, 0, |
| sps_max_dec_pic_buffering_minus1 - st_ref_pic_set.num_negative_pics); |
| |
| for (uint32_t i = 0; i < st_ref_pic_set.num_negative_pics; i++) { |
| // delta_poc_s0_minus1: ue(v) |
| int delta_poc_s0_minus1; |
| delta_poc_s0_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(delta_poc_s0_minus1, 0, 0x7FFF); |
| if (i == 0) { |
| st_ref_pic_set.delta_poc_s0[i] = -(delta_poc_s0_minus1 + 1); |
| } else { |
| st_ref_pic_set.delta_poc_s0[i] = |
| st_ref_pic_set.delta_poc_s0[i - 1] - (delta_poc_s0_minus1 + 1); |
| } |
| // used_by_curr_pic_s0_flag: u(1) |
| st_ref_pic_set.used_by_curr_pic_s0[i] = reader.Read<bool>(); |
| } |
| |
| for (uint32_t i = 0; i < st_ref_pic_set.num_positive_pics; i++) { |
| // delta_poc_s1_minus1: ue(v) |
| int delta_poc_s1_minus1; |
| delta_poc_s1_minus1 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(delta_poc_s1_minus1, 0, 0x7FFF); |
| if (i == 0) { |
| st_ref_pic_set.delta_poc_s1[i] = delta_poc_s1_minus1 + 1; |
| } else { |
| st_ref_pic_set.delta_poc_s1[i] = |
| st_ref_pic_set.delta_poc_s1[i - 1] + delta_poc_s1_minus1 + 1; |
| } |
| // used_by_curr_pic_s1_flag: u(1) |
| st_ref_pic_set.used_by_curr_pic_s1[i] = reader.Read<bool>(); |
| } |
| } |
| |
| st_ref_pic_set.num_delta_pocs = |
| st_ref_pic_set.num_negative_pics + st_ref_pic_set.num_positive_pics; |
| |
| if (!reader.Ok()) { |
| return absl::nullopt; |
| } |
| |
| return OptionalShortTermRefPicSet(st_ref_pic_set); |
| } |
| |
| absl::optional<H265SpsParser::ProfileTierLevel> |
| H265SpsParser::ParseProfileTierLevel(bool profile_present, |
| int max_num_sub_layers_minus1, |
| BitstreamReader& reader) { |
| H265SpsParser::ProfileTierLevel pf_tier_level; |
| // 7.4.4 |
| if (profile_present) { |
| int general_profile_space; |
| general_profile_space = reader.ReadBits(2); |
| TRUE_OR_RETURN(general_profile_space == 0); |
| // general_tier_flag or reserved 0: u(1) |
| reader.ConsumeBits(1); |
| pf_tier_level.general_profile_idc = reader.ReadBits(5); |
| IN_RANGE_OR_RETURN_NULL(pf_tier_level.general_profile_idc, 0, 11); |
| uint16_t general_profile_compatibility_flag_high16; |
| uint16_t general_profile_compatibility_flag_low16; |
| general_profile_compatibility_flag_high16 = reader.ReadBits(16); |
| general_profile_compatibility_flag_low16 = reader.ReadBits(16); |
| pf_tier_level.general_profile_compatibility_flags = |
| (general_profile_compatibility_flag_high16 << 16) + |
| general_profile_compatibility_flag_low16; |
| pf_tier_level.general_progressive_source_flag = reader.ReadBits(1); |
| pf_tier_level.general_interlaced_source_flag = reader.ReadBits(1); |
| if (!reader.Ok() || (!pf_tier_level.general_progressive_source_flag && |
| pf_tier_level.general_interlaced_source_flag)) { |
| RTC_LOG(LS_WARNING) << "Interlaced streams not supported"; |
| return absl::nullopt; |
| } |
| pf_tier_level.general_non_packed_constraint_flag = reader.ReadBits(1); |
| pf_tier_level.general_frame_only_constraint_flag = reader.ReadBits(1); |
| // general_reserved_zero_7bits |
| reader.ConsumeBits(7); |
| pf_tier_level.general_one_picture_only_constraint_flag = reader.ReadBits(1); |
| // general_reserved_zero_35bits |
| reader.ConsumeBits(35); |
| // general_inbld_flag |
| reader.ConsumeBits(1); |
| } |
| pf_tier_level.general_level_idc = reader.ReadBits(8); |
| bool sub_layer_profile_present_flag[8]; |
| bool sub_layer_level_present_flag[8]; |
| for (int i = 0; i < max_num_sub_layers_minus1; ++i) { |
| sub_layer_profile_present_flag[i] = reader.ReadBits(1); |
| sub_layer_level_present_flag[i] = reader.ReadBits(1); |
| } |
| if (max_num_sub_layers_minus1 > 0) { |
| for (int i = max_num_sub_layers_minus1; i < 8; i++) { |
| reader.ConsumeBits(2); |
| } |
| } |
| for (int i = 0; i < max_num_sub_layers_minus1; i++) { |
| if (sub_layer_profile_present_flag[i]) { |
| // sub_layer_profile_space |
| reader.ConsumeBits(2); |
| // sub_layer_tier_flag |
| reader.ConsumeBits(1); |
| // sub_layer_profile_idc |
| reader.ConsumeBits(5); |
| // sub_layer_profile_compatibility_flag |
| reader.ConsumeBits(32); |
| // sub_layer_{progressive,interlaced}_source_flag |
| reader.ConsumeBits(2); |
| // Ignore sub_layer_non_packed_constraint_flag and |
| // sub_layer_frame_only_constraint_flag. |
| reader.ConsumeBits(2); |
| // Skip the compatibility flags, they are always 43 bits. |
| reader.ConsumeBits(43); |
| // sub_layer_inbld_flag |
| reader.ConsumeBits(1); |
| } |
| if (sub_layer_level_present_flag[i]) { |
| // sub_layer_level_idc |
| reader.ConsumeBits(8); |
| } |
| } |
| |
| if (!reader.Ok()) { |
| return absl::nullopt; |
| } |
| |
| return OptionalProfileTierLevel(pf_tier_level); |
| } |
| |
| absl::optional<H265SpsParser::SpsState> H265SpsParser::ParseSpsInternal( |
| rtc::ArrayView<const uint8_t> buffer) { |
| BitstreamReader reader(buffer); |
| |
| // Now, we need to use a bit buffer to parse through the actual H265 SPS |
| // format. See Section 7.3.2.2.1 ("General sequence parameter set data |
| // syntax") of the H.265 standard for a complete description. |
| // Since we only care about resolution, we ignore the majority of fields, but |
| // we still have to actively parse through a lot of the data, since many of |
| // the fields have variable size. |
| // We're particularly interested in: |
| // chroma_format_idc -> affects crop units |
| // pic_{width,height}_* -> resolution of the frame in macroblocks (16x16). |
| // frame_crop_*_offset -> crop information |
| SpsState sps; |
| |
| // sps_video_parameter_set_id: u(4) |
| uint32_t sps_video_parameter_set_id = 0; |
| sps_video_parameter_set_id = reader.ReadBits(4); |
| IN_RANGE_OR_RETURN_NULL(sps_video_parameter_set_id, 0, 15); |
| |
| // sps_max_sub_layers_minus1: u(3) |
| uint32_t sps_max_sub_layers_minus1 = 0; |
| sps_max_sub_layers_minus1 = reader.ReadBits(3); |
| IN_RANGE_OR_RETURN_NULL(sps_max_sub_layers_minus1, 0, kMaxSubLayers - 1); |
| sps.sps_max_sub_layers_minus1 = sps_max_sub_layers_minus1; |
| // sps_temporal_id_nesting_flag: u(1) |
| reader.ConsumeBits(1); |
| // profile_tier_level(1, sps_max_sub_layers_minus1). |
| OptionalProfileTierLevel profile_tier_level = |
| ParseProfileTierLevel(true, sps.sps_max_sub_layers_minus1, reader); |
| if (!profile_tier_level) { |
| return absl::nullopt; |
| } |
| // sps_seq_parameter_set_id: ue(v) |
| sps.sps_id = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.sps_id, 0, 15); |
| // chrome_format_idc: ue(v) |
| sps.chroma_format_idc = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.chroma_format_idc, 0, 3); |
| if (sps.chroma_format_idc == 3) { |
| // seperate_colour_plane_flag: u(1) |
| sps.separate_colour_plane_flag = reader.Read<bool>(); |
| } |
| uint32_t pic_width_in_luma_samples = 0; |
| uint32_t pic_height_in_luma_samples = 0; |
| // pic_width_in_luma_samples: ue(v) |
| pic_width_in_luma_samples = reader.ReadExponentialGolomb(); |
| TRUE_OR_RETURN(pic_width_in_luma_samples != 0); |
| // pic_height_in_luma_samples: ue(v) |
| pic_height_in_luma_samples = reader.ReadExponentialGolomb(); |
| TRUE_OR_RETURN(pic_height_in_luma_samples != 0); |
| |
| // Equation A-2: Calculate max_dpb_size. |
| uint32_t max_luma_ps = GetMaxLumaPs(profile_tier_level->general_level_idc); |
| uint32_t max_dpb_size; |
| uint32_t pic_size_in_samples_y = pic_height_in_luma_samples; |
| pic_size_in_samples_y *= pic_width_in_luma_samples; |
| size_t max_dpb_pic_buf = |
| GetDpbMaxPicBuf(profile_tier_level->general_profile_idc); |
| if (pic_size_in_samples_y <= (max_luma_ps >> 2)) |
| max_dpb_size = std::min(4 * max_dpb_pic_buf, size_t{16}); |
| else if (pic_size_in_samples_y <= (max_luma_ps >> 1)) |
| max_dpb_size = std::min(2 * max_dpb_pic_buf, size_t{16}); |
| else if (pic_size_in_samples_y <= ((3 * max_luma_ps) >> 2)) |
| max_dpb_size = std::min((4 * max_dpb_pic_buf) / 3, size_t{16}); |
| else |
| max_dpb_size = max_dpb_pic_buf; |
| |
| // conformance_window_flag: u(1) |
| bool conformance_window_flag = reader.Read<bool>(); |
| |
| uint32_t conf_win_left_offset = 0; |
| uint32_t conf_win_right_offset = 0; |
| uint32_t conf_win_top_offset = 0; |
| uint32_t conf_win_bottom_offset = 0; |
| int sub_width_c = |
| ((1 == sps.chroma_format_idc) || (2 == sps.chroma_format_idc)) && |
| (0 == sps.separate_colour_plane_flag) |
| ? 2 |
| : 1; |
| int sub_height_c = |
| (1 == sps.chroma_format_idc) && (0 == sps.separate_colour_plane_flag) ? 2 |
| : 1; |
| if (conformance_window_flag) { |
| // conf_win_left_offset: ue(v) |
| conf_win_left_offset = reader.ReadExponentialGolomb(); |
| // conf_win_right_offset: ue(v) |
| conf_win_right_offset = reader.ReadExponentialGolomb(); |
| // conf_win_top_offset: ue(v) |
| conf_win_top_offset = reader.ReadExponentialGolomb(); |
| // conf_win_bottom_offset: ue(v) |
| conf_win_bottom_offset = reader.ReadExponentialGolomb(); |
| uint32_t width_crop = conf_win_left_offset; |
| width_crop += conf_win_right_offset; |
| width_crop *= sub_width_c; |
| TRUE_OR_RETURN(width_crop < pic_width_in_luma_samples); |
| uint32_t height_crop = conf_win_top_offset; |
| height_crop += conf_win_bottom_offset; |
| height_crop *= sub_height_c; |
| TRUE_OR_RETURN(height_crop < pic_height_in_luma_samples); |
| } |
| |
| // bit_depth_luma_minus8: ue(v) |
| sps.bit_depth_luma_minus8 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.bit_depth_luma_minus8, 0, 8); |
| // bit_depth_chroma_minus8: ue(v) |
| uint32_t bit_depth_chroma_minus8 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(bit_depth_chroma_minus8, 0, 8); |
| // log2_max_pic_order_cnt_lsb_minus4: ue(v) |
| sps.log2_max_pic_order_cnt_lsb_minus4 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.log2_max_pic_order_cnt_lsb_minus4, 0, 12); |
| uint32_t sps_sub_layer_ordering_info_present_flag = 0; |
| // sps_sub_layer_ordering_info_present_flag: u(1) |
| sps_sub_layer_ordering_info_present_flag = reader.Read<bool>(); |
| uint32_t sps_max_num_reorder_pics[kMaxSubLayers]; |
| for (uint32_t i = (sps_sub_layer_ordering_info_present_flag != 0) |
| ? 0 |
| : sps_max_sub_layers_minus1; |
| i <= sps_max_sub_layers_minus1; i++) { |
| // sps_max_dec_pic_buffering_minus1: ue(v) |
| sps.sps_max_dec_pic_buffering_minus1[i] = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.sps_max_dec_pic_buffering_minus1[i], 0, |
| max_dpb_size - 1); |
| // sps_max_num_reorder_pics: ue(v) |
| sps_max_num_reorder_pics[i] = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps_max_num_reorder_pics[i], 0, |
| sps.sps_max_dec_pic_buffering_minus1[i]); |
| if (i > 0) { |
| TRUE_OR_RETURN(sps.sps_max_dec_pic_buffering_minus1[i] >= |
| sps.sps_max_dec_pic_buffering_minus1[i - 1]); |
| TRUE_OR_RETURN(sps_max_num_reorder_pics[i] >= |
| sps_max_num_reorder_pics[i - 1]); |
| } |
| // sps_max_latency_increase_plus1: ue(v) |
| reader.ReadExponentialGolomb(); |
| } |
| if (!sps_sub_layer_ordering_info_present_flag) { |
| // Fill in the default values for the other sublayers. |
| for (uint32_t i = 0; i < sps_max_sub_layers_minus1; ++i) { |
| sps.sps_max_dec_pic_buffering_minus1[i] = |
| sps.sps_max_dec_pic_buffering_minus1[sps_max_sub_layers_minus1]; |
| } |
| } |
| // log2_min_luma_coding_block_size_minus3: ue(v) |
| sps.log2_min_luma_coding_block_size_minus3 = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.log2_min_luma_coding_block_size_minus3, 0, 27); |
| // log2_diff_max_min_luma_coding_block_size: ue(v) |
| sps.log2_diff_max_min_luma_coding_block_size = reader.ReadExponentialGolomb(); |
| int min_cb_log2_size_y = sps.log2_min_luma_coding_block_size_minus3 + 3; |
| int ctb_log2_size_y = min_cb_log2_size_y; |
| ctb_log2_size_y += sps.log2_diff_max_min_luma_coding_block_size; |
| IN_RANGE_OR_RETURN_NULL(ctb_log2_size_y, 0, 30); |
| int min_cb_size_y = 1 << min_cb_log2_size_y; |
| int ctb_size_y = 1 << ctb_log2_size_y; |
| sps.pic_width_in_ctbs_y = |
| std::ceil(static_cast<float>(pic_width_in_luma_samples) / ctb_size_y); |
| sps.pic_height_in_ctbs_y = |
| std::ceil(static_cast<float>(pic_height_in_luma_samples) / ctb_size_y); |
| TRUE_OR_RETURN(pic_width_in_luma_samples % min_cb_size_y == 0); |
| TRUE_OR_RETURN(pic_height_in_luma_samples % min_cb_size_y == 0); |
| // log2_min_luma_transform_block_size_minus2: ue(v) |
| int log2_min_luma_transform_block_size_minus2 = |
| reader.ReadExponentialGolomb(); |
| TRUE_OR_RETURN(log2_min_luma_transform_block_size_minus2 < |
| min_cb_log2_size_y - 2); |
| int min_tb_log2_size_y = log2_min_luma_transform_block_size_minus2 + 2; |
| // log2_diff_max_min_luma_transform_block_size: ue(v) |
| int log2_diff_max_min_luma_transform_block_size = |
| reader.ReadExponentialGolomb(); |
| TRUE_OR_RETURN(log2_diff_max_min_luma_transform_block_size <= |
| std::min(ctb_log2_size_y, 5) - min_tb_log2_size_y); |
| // max_transform_hierarchy_depth_inter: ue(v) |
| int max_transform_hierarchy_depth_inter = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(max_transform_hierarchy_depth_inter, 0, |
| ctb_log2_size_y - min_tb_log2_size_y); |
| // max_transform_hierarchy_depth_intra: ue(v) |
| int max_transform_hierarchy_depth_intra = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(max_transform_hierarchy_depth_intra, 0, |
| ctb_log2_size_y - min_tb_log2_size_y); |
| // scaling_list_enabled_flag: u(1) |
| bool scaling_list_enabled_flag = reader.Read<bool>(); |
| if (scaling_list_enabled_flag) { |
| // sps_scaling_list_data_present_flag: u(1) |
| bool sps_scaling_list_data_present_flag = reader.Read<bool>(); |
| if (sps_scaling_list_data_present_flag) { |
| // scaling_list_data() |
| if (!ParseScalingListData(reader)) { |
| return absl::nullopt; |
| } |
| } |
| } |
| |
| // amp_enabled_flag: u(1) |
| reader.ConsumeBits(1); |
| // sample_adaptive_offset_enabled_flag: u(1) |
| sps.sample_adaptive_offset_enabled_flag = reader.Read<bool>(); |
| // pcm_enabled_flag: u(1) |
| bool pcm_enabled_flag = reader.Read<bool>(); |
| if (pcm_enabled_flag) { |
| // pcm_sample_bit_depth_luma_minus1: u(4) |
| reader.ConsumeBits(4); |
| // pcm_sample_bit_depth_chroma_minus1: u(4) |
| reader.ConsumeBits(4); |
| // log2_min_pcm_luma_coding_block_size_minus3: ue(v) |
| int log2_min_pcm_luma_coding_block_size_minus3 = |
| reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(log2_min_pcm_luma_coding_block_size_minus3, 0, 2); |
| int log2_min_ipcm_cb_size_y = |
| log2_min_pcm_luma_coding_block_size_minus3 + 3; |
| IN_RANGE_OR_RETURN_NULL(log2_min_ipcm_cb_size_y, |
| std::min(min_cb_log2_size_y, 5), |
| std::min(ctb_log2_size_y, 5)); |
| // log2_diff_max_min_pcm_luma_coding_block_size: ue(v) |
| int log2_diff_max_min_pcm_luma_coding_block_size = |
| reader.ReadExponentialGolomb(); |
| TRUE_OR_RETURN(log2_diff_max_min_pcm_luma_coding_block_size <= |
| std::min(ctb_log2_size_y, 5) - log2_min_ipcm_cb_size_y); |
| // pcm_loop_filter_disabled_flag: u(1) |
| reader.ConsumeBits(1); |
| } |
| |
| // num_short_term_ref_pic_sets: ue(v) |
| sps.num_short_term_ref_pic_sets = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.num_short_term_ref_pic_sets, 0, |
| kMaxShortTermRefPicSets); |
| sps.short_term_ref_pic_set.resize(sps.num_short_term_ref_pic_sets); |
| for (uint32_t st_rps_idx = 0; st_rps_idx < sps.num_short_term_ref_pic_sets; |
| st_rps_idx++) { |
| uint32_t sps_max_dec_pic_buffering_minus1 = |
| sps.sps_max_dec_pic_buffering_minus1[sps.sps_max_sub_layers_minus1]; |
| // st_ref_pic_set() |
| OptionalShortTermRefPicSet ref_pic_set = ParseShortTermRefPicSet( |
| st_rps_idx, sps.num_short_term_ref_pic_sets, sps.short_term_ref_pic_set, |
| sps_max_dec_pic_buffering_minus1, reader); |
| if (ref_pic_set) { |
| sps.short_term_ref_pic_set[st_rps_idx] = *ref_pic_set; |
| } else { |
| return absl::nullopt; |
| } |
| } |
| |
| // long_term_ref_pics_present_flag: u(1) |
| sps.long_term_ref_pics_present_flag = reader.Read<bool>(); |
| if (sps.long_term_ref_pics_present_flag) { |
| // num_long_term_ref_pics_sps: ue(v) |
| sps.num_long_term_ref_pics_sps = reader.ReadExponentialGolomb(); |
| IN_RANGE_OR_RETURN_NULL(sps.num_long_term_ref_pics_sps, 0, |
| kMaxLongTermRefPicSets); |
| sps.lt_ref_pic_poc_lsb_sps.resize(sps.num_long_term_ref_pics_sps, 0); |
| sps.used_by_curr_pic_lt_sps_flag.resize(sps.num_long_term_ref_pics_sps, 0); |
| for (uint32_t i = 0; i < sps.num_long_term_ref_pics_sps; i++) { |
| // lt_ref_pic_poc_lsb_sps: u(v) |
| uint32_t lt_ref_pic_poc_lsb_sps_bits = |
| sps.log2_max_pic_order_cnt_lsb_minus4 + 4; |
| sps.lt_ref_pic_poc_lsb_sps[i] = |
| reader.ReadBits(lt_ref_pic_poc_lsb_sps_bits); |
| // used_by_curr_pic_lt_sps_flag: u(1) |
| sps.used_by_curr_pic_lt_sps_flag[i] = reader.Read<bool>(); |
| } |
| } |
| |
| // sps_temporal_mvp_enabled_flag: u(1) |
| sps.sps_temporal_mvp_enabled_flag = reader.Read<bool>(); |
| |
| // Far enough! We don't use the rest of the SPS. |
| |
| sps.vps_id = sps_video_parameter_set_id; |
| |
| sps.pic_width_in_luma_samples = pic_width_in_luma_samples; |
| sps.pic_height_in_luma_samples = pic_height_in_luma_samples; |
| |
| // Start with the resolution determined by the pic_width/pic_height fields. |
| sps.width = pic_width_in_luma_samples; |
| sps.height = pic_height_in_luma_samples; |
| |
| if (conformance_window_flag) { |
| int sub_width_c = |
| ((1 == sps.chroma_format_idc) || (2 == sps.chroma_format_idc)) && |
| (0 == sps.separate_colour_plane_flag) |
| ? 2 |
| : 1; |
| int sub_height_c = |
| (1 == sps.chroma_format_idc) && (0 == sps.separate_colour_plane_flag) |
| ? 2 |
| : 1; |
| // the offset includes the pixel within conformance window. so don't need to |
| // +1 as per spec |
| sps.width -= sub_width_c * (conf_win_right_offset + conf_win_left_offset); |
| sps.height -= sub_height_c * (conf_win_top_offset + conf_win_bottom_offset); |
| } |
| |
| if (!reader.Ok()) { |
| return absl::nullopt; |
| } |
| |
| return OptionalSps(sps); |
| } |
| |
| } // namespace webrtc |
