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Unified Diff: webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.cc

Issue 2007553003: Move H264BitstreamParser to video_coding. (Closed) Base URL: https://chromium.googlesource.com/external/webrtc.git@master
Patch Set: Created 4 years, 7 months ago
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Index: webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.cc
diff --git a/webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.cc b/webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.cc
deleted file mode 100644
index e23a3fa629bf203961bc074f084ebd303a629189..0000000000000000000000000000000000000000
--- a/webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.cc
+++ /dev/null
@@ -1,565 +0,0 @@
-/*
- * Copyright (c) 2015 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 "webrtc/modules/rtp_rtcp/source/h264_bitstream_parser.h"
-
-#include <memory>
-#include <vector>
-
-#include "webrtc/base/bitbuffer.h"
-#include "webrtc/base/bytebuffer.h"
-#include "webrtc/base/checks.h"
-#include "webrtc/base/logging.h"
-
-namespace webrtc {
-namespace {
-// The size of a NALU header {0 0 0 1}.
-static const size_t kNaluHeaderSize = 4;
-
-// The size of a NALU header plus the type byte.
-static const size_t kNaluHeaderAndTypeSize = kNaluHeaderSize + 1;
-
-// The NALU type.
-static const uint8_t kNaluSps = 0x7;
-static const uint8_t kNaluPps = 0x8;
-static const uint8_t kNaluIdr = 0x5;
-static const uint8_t kNaluTypeMask = 0x1F;
-
-static const uint8_t kSliceTypeP = 0x0;
-static const uint8_t kSliceTypeB = 0x1;
-static const uint8_t kSliceTypeSp = 0x3;
-
-// Returns a vector of the NALU start sequences (0 0 0 1) in the given buffer.
-std::vector<size_t> FindNaluStartSequences(const uint8_t* buffer,
- size_t buffer_size) {
- std::vector<size_t> sequences;
- // This is sorta like Boyer-Moore, but with only the first optimization step:
- // given a 4-byte sequence we're looking at, if the 4th byte isn't 1 or 0,
- // skip ahead to the next 4-byte sequence. 0s and 1s are relatively rare, so
- // this will skip the majority of reads/checks.
- const uint8_t* end = buffer + buffer_size - 4;
- for (const uint8_t* head = buffer; head < end;) {
- if (head[3] > 1) {
- head += 4;
- } else if (head[3] == 1 && head[2] == 0 && head[1] == 0 && head[0] == 0) {
- sequences.push_back(static_cast<size_t>(head - buffer));
- head += 4;
- } else {
- head++;
- }
- }
-
- return sequences;
-}
-} // namespace
-
-// Parses RBSP from source bytes. Removes emulation bytes, but leaves the
-// rbsp_trailing_bits() in the stream, since none of the parsing reads all the
-// way to the end of a parsed RBSP sequence. When writing, that means the
-// rbsp_trailing_bits() should be preserved and don't need to be restored (i.e.
-// the rbsp_stop_one_bit, which is just a 1, then zero padded), and alignment
-// should "just work".
-// TODO(pbos): Make parsing RBSP something that can be integrated into BitBuffer
-// so we don't have to copy the entire frames when only interested in the
-// headers.
-rtc::ByteBufferWriter* ParseRbsp(const uint8_t* bytes, size_t length) {
- // Copied from webrtc::H264SpsParser::Parse.
- rtc::ByteBufferWriter* rbsp_buffer = new rtc::ByteBufferWriter();
- for (size_t i = 0; i < length;) {
- if (length - i >= 3 && bytes[i] == 0 && bytes[i + 1] == 0 &&
- bytes[i + 2] == 3) {
- rbsp_buffer->WriteBytes(reinterpret_cast<const char*>(bytes) + i, 2);
- i += 3;
- } else {
- rbsp_buffer->WriteBytes(reinterpret_cast<const char*>(bytes) + i, 1);
- i++;
- }
- }
- return rbsp_buffer;
-}
-
-#define RETURN_FALSE_ON_FAIL(x) \
- if (!(x)) { \
- LOG_F(LS_ERROR) << "FAILED: " #x; \
- return false; \
- }
-
-H264BitstreamParser::PpsState::PpsState() {}
-
-H264BitstreamParser::SpsState::SpsState() {}
-
-// These functions are similar to webrtc::H264SpsParser::Parse, and based on the
-// same version of the H.264 standard. You can find it here:
-// http://www.itu.int/rec/T-REC-H.264
-bool H264BitstreamParser::ParseSpsNalu(const uint8_t* sps, size_t length) {
- // Reset SPS state.
- sps_ = SpsState();
- sps_parsed_ = false;
- // Parse out the SPS RBSP. It should be small, so it's ok that we create a
- // copy. We'll eventually write this back.
- std::unique_ptr<rtc::ByteBufferWriter> sps_rbsp(
- ParseRbsp(sps + kNaluHeaderAndTypeSize, length - kNaluHeaderAndTypeSize));
- rtc::BitBuffer sps_parser(reinterpret_cast<const uint8_t*>(sps_rbsp->Data()),
- sps_rbsp->Length());
-
- uint8_t byte_tmp;
- uint32_t golomb_tmp;
- uint32_t bits_tmp;
-
- // profile_idc: u(8).
- uint8_t profile_idc;
- RETURN_FALSE_ON_FAIL(sps_parser.ReadUInt8(&profile_idc));
- // constraint_set0_flag through constraint_set5_flag + reserved_zero_2bits
- // 1 bit each for the flags + 2 bits = 8 bits = 1 byte.
- RETURN_FALSE_ON_FAIL(sps_parser.ReadUInt8(&byte_tmp));
- // level_idc: u(8)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadUInt8(&byte_tmp));
- // seq_parameter_set_id: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- sps_.separate_colour_plane_flag = 0;
- // See if profile_idc has chroma format information.
- if (profile_idc == 100 || profile_idc == 110 || profile_idc == 122 ||
- profile_idc == 244 || profile_idc == 44 || profile_idc == 83 ||
- profile_idc == 86 || profile_idc == 118 || profile_idc == 128 ||
- profile_idc == 138 || profile_idc == 139 || profile_idc == 134) {
- // chroma_format_idc: ue(v)
- uint32_t chroma_format_idc;
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&chroma_format_idc));
- if (chroma_format_idc == 3) {
- // separate_colour_plane_flag: u(1)
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadBits(&sps_.separate_colour_plane_flag, 1));
- }
- // bit_depth_luma_minus8: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // bit_depth_chroma_minus8: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // qpprime_y_zero_transform_bypass_flag: u(1)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadBits(&bits_tmp, 1));
- // seq_scaling_matrix_present_flag: u(1)
- uint32_t seq_scaling_matrix_present_flag;
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadBits(&seq_scaling_matrix_present_flag, 1));
- if (seq_scaling_matrix_present_flag) {
- // seq_scaling_list_present_flags. Either 8 or 12, depending on
- // chroma_format_idc.
- uint32_t seq_scaling_list_present_flags;
- if (chroma_format_idc != 3) {
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadBits(&seq_scaling_list_present_flags, 8));
- } else {
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadBits(&seq_scaling_list_present_flags, 12));
- }
- // TODO(pbos): Support parsing scaling lists if they're seen in practice.
- RTC_CHECK(seq_scaling_list_present_flags == 0)
- << "SPS contains scaling lists, which are unsupported.";
- }
- }
- // log2_max_frame_num_minus4: ue(v)
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadExponentialGolomb(&sps_.log2_max_frame_num_minus4));
- // pic_order_cnt_type: ue(v)
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadExponentialGolomb(&sps_.pic_order_cnt_type));
-
- if (sps_.pic_order_cnt_type == 0) {
- // log2_max_pic_order_cnt_lsb_minus4: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(
- &sps_.log2_max_pic_order_cnt_lsb_minus4));
- } else if (sps_.pic_order_cnt_type == 1) {
- // delta_pic_order_always_zero_flag: u(1)
- RETURN_FALSE_ON_FAIL(
- sps_parser.ReadBits(&sps_.delta_pic_order_always_zero_flag, 1));
- // offset_for_non_ref_pic: se(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // offset_for_top_to_bottom_field: se(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- uint32_t num_ref_frames_in_pic_order_cnt_cycle;
- // num_ref_frames_in_pic_order_cnt_cycle: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(
- &num_ref_frames_in_pic_order_cnt_cycle));
- for (uint32_t i = 0; i < num_ref_frames_in_pic_order_cnt_cycle; i++) {
- // offset_for_ref_frame[i]: se(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- }
- }
- // max_num_ref_frames: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // gaps_in_frame_num_value_allowed_flag: u(1)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadBits(&bits_tmp, 1));
- // pic_width_in_mbs_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // pic_height_in_map_units_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadExponentialGolomb(&golomb_tmp));
- // frame_mbs_only_flag: u(1)
- RETURN_FALSE_ON_FAIL(sps_parser.ReadBits(&sps_.frame_mbs_only_flag, 1));
- sps_parsed_ = true;
- return true;
-}
-
-bool H264BitstreamParser::ParsePpsNalu(const uint8_t* pps, size_t length) {
- RTC_CHECK(sps_parsed_);
- // We're starting a new stream, so reset picture type rewriting values.
- pps_ = PpsState();
- pps_parsed_ = false;
- std::unique_ptr<rtc::ByteBufferWriter> buffer(
- ParseRbsp(pps + kNaluHeaderAndTypeSize, length - kNaluHeaderAndTypeSize));
- rtc::BitBuffer parser(reinterpret_cast<const uint8_t*>(buffer->Data()),
- buffer->Length());
-
- uint32_t bits_tmp;
- uint32_t golomb_ignored;
- // pic_parameter_set_id: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // seq_parameter_set_id: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // entropy_coding_mode_flag: u(1)
- uint32_t entropy_coding_mode_flag;
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&entropy_coding_mode_flag, 1));
- // TODO(pbos): Implement CABAC support if spotted in the wild.
- RTC_CHECK(entropy_coding_mode_flag == 0)
- << "Don't know how to parse CABAC streams.";
- // bottom_field_pic_order_in_frame_present_flag: u(1)
- uint32_t bottom_field_pic_order_in_frame_present_flag;
- RETURN_FALSE_ON_FAIL(
- parser.ReadBits(&bottom_field_pic_order_in_frame_present_flag, 1));
- pps_.bottom_field_pic_order_in_frame_present_flag =
- bottom_field_pic_order_in_frame_present_flag != 0;
-
- // num_slice_groups_minus1: ue(v)
- uint32_t num_slice_groups_minus1;
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&num_slice_groups_minus1));
- if (num_slice_groups_minus1 > 0) {
- uint32_t slice_group_map_type;
- // slice_group_map_type: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&slice_group_map_type));
- if (slice_group_map_type == 0) {
- for (uint32_t i_group = 0; i_group <= num_slice_groups_minus1;
- ++i_group) {
- // run_length_minus1[iGroup]: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- }
- } else if (slice_group_map_type == 2) {
- for (uint32_t i_group = 0; i_group <= num_slice_groups_minus1;
- ++i_group) {
- // top_left[iGroup]: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // bottom_right[iGroup]: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- }
- } else if (slice_group_map_type == 3 || slice_group_map_type == 4 ||
- slice_group_map_type == 5) {
- // slice_group_change_direction_flag: u(1)
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&bits_tmp, 1));
- // slice_group_change_rate_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- } else if (slice_group_map_type == 6) {
- // pic_size_in_map_units_minus1: ue(v)
- uint32_t pic_size_in_map_units_minus1;
- RETURN_FALSE_ON_FAIL(
- parser.ReadExponentialGolomb(&pic_size_in_map_units_minus1));
- uint32_t slice_group_id_bits = 0;
- uint32_t num_slice_groups = num_slice_groups_minus1 + 1;
- // If num_slice_groups is not a power of two an additional bit is required
- // to account for the ceil() of log2() below.
- if ((num_slice_groups & (num_slice_groups - 1)) != 0)
- ++slice_group_id_bits;
- while (num_slice_groups > 0) {
- num_slice_groups >>= 1;
- ++slice_group_id_bits;
- }
- for (uint32_t i = 0; i <= pic_size_in_map_units_minus1; i++) {
- // slice_group_id[i]: u(v)
- // Represented by ceil(log2(num_slice_groups_minus1 + 1)) bits.
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&bits_tmp, slice_group_id_bits));
- }
- }
- }
- // num_ref_idx_l0_default_active_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // num_ref_idx_l1_default_active_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // weighted_pred_flag: u(1)
- uint32_t weighted_pred_flag;
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&weighted_pred_flag, 1));
- pps_.weighted_pred_flag = weighted_pred_flag != 0;
- // weighted_bipred_idc: u(2)
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&pps_.weighted_bipred_idc, 2));
-
- // pic_init_qp_minus26: se(v)
- RETURN_FALSE_ON_FAIL(
- parser.ReadSignedExponentialGolomb(&pps_.pic_init_qp_minus26));
- // pic_init_qs_minus26: se(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // chroma_qp_index_offset: se(v)
- RETURN_FALSE_ON_FAIL(parser.ReadExponentialGolomb(&golomb_ignored));
- // deblocking_filter_control_present_flag: u(1)
- // constrained_intra_pred_flag: u(1)
- RETURN_FALSE_ON_FAIL(parser.ReadBits(&bits_tmp, 2));
- // redundant_pic_cnt_present_flag: u(1)
- RETURN_FALSE_ON_FAIL(
- parser.ReadBits(&pps_.redundant_pic_cnt_present_flag, 1));
-
- pps_parsed_ = true;
- return true;
-}
-
-bool H264BitstreamParser::ParseNonParameterSetNalu(const uint8_t* source,
- size_t source_length,
- uint8_t nalu_type) {
- RTC_CHECK(sps_parsed_);
- RTC_CHECK(pps_parsed_);
- last_slice_qp_delta_parsed_ = false;
- std::unique_ptr<rtc::ByteBufferWriter> slice_rbsp(ParseRbsp(
- source + kNaluHeaderAndTypeSize, source_length - kNaluHeaderAndTypeSize));
- rtc::BitBuffer slice_reader(
- reinterpret_cast<const uint8_t*>(slice_rbsp->Data()),
- slice_rbsp->Length());
- // Check to see if this is an IDR slice, which has an extra field to parse
- // out.
- bool is_idr = (source[kNaluHeaderSize] & 0x0F) == kNaluIdr;
- uint8_t nal_ref_idc = (source[kNaluHeaderSize] & 0x60) >> 5;
- uint32_t golomb_tmp;
- uint32_t bits_tmp;
-
- // first_mb_in_slice: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- // slice_type: ue(v)
- uint32_t slice_type;
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&slice_type));
- // slice_type's 5..9 range is used to indicate that all slices of a picture
- // have the same value of slice_type % 5, we don't care about that, so we map
- // to the corresponding 0..4 range.
- slice_type %= 5;
- // pic_parameter_set_id: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- if (sps_.separate_colour_plane_flag == 1) {
- // colour_plane_id
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(&bits_tmp, 2));
- }
- // frame_num: u(v)
- // Represented by log2_max_frame_num_minus4 + 4 bits.
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadBits(&bits_tmp, sps_.log2_max_frame_num_minus4 + 4));
- uint32_t field_pic_flag = 0;
- if (sps_.frame_mbs_only_flag == 0) {
- // field_pic_flag: u(1)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(&field_pic_flag, 1));
- if (field_pic_flag != 0) {
- // bottom_field_flag: u(1)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(&bits_tmp, 1));
- }
- }
- if (is_idr) {
- // idr_pic_id: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- // pic_order_cnt_lsb: u(v)
- // Represented by sps_.log2_max_pic_order_cnt_lsb_minus4 + 4 bits.
- if (sps_.pic_order_cnt_type == 0) {
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(
- &bits_tmp, sps_.log2_max_pic_order_cnt_lsb_minus4 + 4));
- if (pps_.bottom_field_pic_order_in_frame_present_flag &&
- field_pic_flag == 0) {
- // delta_pic_order_cnt_bottom: se(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- }
- if (sps_.pic_order_cnt_type == 1 && !sps_.delta_pic_order_always_zero_flag) {
- // delta_pic_order_cnt[0]: se(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- if (pps_.bottom_field_pic_order_in_frame_present_flag && !field_pic_flag) {
- // delta_pic_order_cnt[1]: se(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- }
- if (pps_.redundant_pic_cnt_present_flag) {
- // redundant_pic_cnt: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- if (slice_type == kSliceTypeB) {
- // direct_spatial_mv_pred_flag: u(1)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(&bits_tmp, 1));
- }
- if (slice_type == kSliceTypeP || slice_type == kSliceTypeSp ||
- slice_type == kSliceTypeB) {
- uint32_t num_ref_idx_active_override_flag;
- // num_ref_idx_active_override_flag: u(1)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadBits(&num_ref_idx_active_override_flag, 1));
- if (num_ref_idx_active_override_flag != 0) {
- // num_ref_idx_l0_active_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- if (slice_type == kSliceTypeB) {
- // num_ref_idx_l1_active_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- }
- }
- // assume nal_unit_type != 20 && nal_unit_type != 21:
- RTC_CHECK_NE(nalu_type, 20);
- RTC_CHECK_NE(nalu_type, 21);
- // if (nal_unit_type == 20 || nal_unit_type == 21)
- // ref_pic_list_mvc_modification()
- // else
- {
- // ref_pic_list_modification():
- // |slice_type| checks here don't use named constants as they aren't named
- // in the spec for this segment. Keeping them consistent makes it easier to
- // verify that they are both the same.
- if (slice_type % 5 != 2 && slice_type % 5 != 4) {
- // ref_pic_list_modification_flag_l0: u(1)
- uint32_t ref_pic_list_modification_flag_l0;
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadBits(&ref_pic_list_modification_flag_l0, 1));
- if (ref_pic_list_modification_flag_l0) {
- uint32_t modification_of_pic_nums_idc;
- do {
- // modification_of_pic_nums_idc: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(
- &modification_of_pic_nums_idc));
- if (modification_of_pic_nums_idc == 0 ||
- modification_of_pic_nums_idc == 1) {
- // abs_diff_pic_num_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- } else if (modification_of_pic_nums_idc == 2) {
- // long_term_pic_num: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- } while (modification_of_pic_nums_idc != 3);
- }
- }
- if (slice_type % 5 == 1) {
- // ref_pic_list_modification_flag_l1: u(1)
- uint32_t ref_pic_list_modification_flag_l1;
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadBits(&ref_pic_list_modification_flag_l1, 1));
- if (ref_pic_list_modification_flag_l1) {
- uint32_t modification_of_pic_nums_idc;
- do {
- // modification_of_pic_nums_idc: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(
- &modification_of_pic_nums_idc));
- if (modification_of_pic_nums_idc == 0 ||
- modification_of_pic_nums_idc == 1) {
- // abs_diff_pic_num_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- } else if (modification_of_pic_nums_idc == 2) {
- // long_term_pic_num: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- } while (modification_of_pic_nums_idc != 3);
- }
- }
- }
- // TODO(pbos): Do we need support for pred_weight_table()?
- RTC_CHECK(!((pps_.weighted_pred_flag &&
- (slice_type == kSliceTypeP || slice_type == kSliceTypeSp)) ||
- (pps_.weighted_bipred_idc != 0 && slice_type == kSliceTypeB)))
- << "Missing support for pred_weight_table().";
- // if ((weighted_pred_flag && (slice_type == P || slice_type == SP)) ||
- // (weighted_bipred_idc == 1 && slice_type == B)) {
- // pred_weight_table()
- // }
- if (nal_ref_idc != 0) {
- // dec_ref_pic_marking():
- if (is_idr) {
- // no_output_of_prior_pics_flag: u(1)
- // long_term_reference_flag: u(1)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadBits(&bits_tmp, 2));
- } else {
- // adaptive_ref_pic_marking_mode_flag: u(1)
- uint32_t adaptive_ref_pic_marking_mode_flag;
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadBits(&adaptive_ref_pic_marking_mode_flag, 1));
- if (adaptive_ref_pic_marking_mode_flag) {
- uint32_t memory_management_control_operation;
- do {
- // memory_management_control_operation: ue(v)
- RETURN_FALSE_ON_FAIL(slice_reader.ReadExponentialGolomb(
- &memory_management_control_operation));
- if (memory_management_control_operation == 1 ||
- memory_management_control_operation == 3) {
- // difference_of_pic_nums_minus1: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- if (memory_management_control_operation == 2) {
- // long_term_pic_num: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- if (memory_management_control_operation == 3 ||
- memory_management_control_operation == 6) {
- // long_term_frame_idx: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- if (memory_management_control_operation == 4) {
- // max_long_term_frame_idx_plus1: ue(v)
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadExponentialGolomb(&golomb_tmp));
- }
- } while (memory_management_control_operation != 0);
- }
- }
- }
- // cabac not supported: entropy_coding_mode_flag == 0 asserted above.
- // if (entropy_coding_mode_flag && slice_type != I && slice_type != SI)
- // cabac_init_idc
- RETURN_FALSE_ON_FAIL(
- slice_reader.ReadSignedExponentialGolomb(&last_slice_qp_delta_));
- last_slice_qp_delta_parsed_ = true;
- return true;
-}
-
-void H264BitstreamParser::ParseSlice(const uint8_t* slice, size_t length) {
- uint8_t nalu_type = slice[4] & kNaluTypeMask;
- switch (nalu_type) {
- case kNaluSps:
- RTC_CHECK(ParseSpsNalu(slice, length))
- << "Failed to parse bitstream SPS.";
- break;
- case kNaluPps:
- RTC_CHECK(ParsePpsNalu(slice, length))
- << "Failed to parse bitstream PPS.";
- break;
- default:
- RTC_CHECK(ParseNonParameterSetNalu(slice, length, nalu_type))
- << "Failed to parse picture slice.";
- break;
- }
-}
-
-void H264BitstreamParser::ParseBitstream(const uint8_t* bitstream,
- size_t length) {
- RTC_CHECK_GE(length, 4u);
- std::vector<size_t> slice_markers = FindNaluStartSequences(bitstream, length);
- RTC_CHECK(!slice_markers.empty());
- for (size_t i = 0; i < slice_markers.size() - 1; ++i) {
- ParseSlice(bitstream + slice_markers[i],
- slice_markers[i + 1] - slice_markers[i]);
- }
- // Parse the last slice.
- ParseSlice(bitstream + slice_markers.back(), length - slice_markers.back());
-}
-
-bool H264BitstreamParser::GetLastSliceQp(int* qp) const {
- if (!last_slice_qp_delta_parsed_)
- return false;
- *qp = 26 + pps_.pic_init_qp_minus26 + last_slice_qp_delta_;
- return true;
-}
-
-} // namespace webrtc

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