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chromium / chromium / src / media / refs/heads/main / . / video / h264_parser.cc
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// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/video/h264_parser.h"
#include <cstring>
#include <limits>
#include <memory>
#include "base/logging.h"
#include "base/notreached.h"
#include "base/numerics/safe_math.h"
#include "media/base/subsample_entry.h"
#include "media/video/bit_reader_macros.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/hdr_metadata.h"
namespace media {
bool H264SliceHeader::IsPSlice() const {
return (slice_type % 5 == kPSlice);
}
bool H264SliceHeader::IsBSlice() const {
return (slice_type % 5 == kBSlice);
}
bool H264SliceHeader::IsISlice() const {
return (slice_type % 5 == kISlice);
}
bool H264SliceHeader::IsSPSlice() const {
return (slice_type % 5 == kSPSlice);
}
bool H264SliceHeader::IsSISlice() const {
return (slice_type % 5 == kSISlice);
}
H264NALU::H264NALU() {
memset(this, 0, sizeof(*this));
}
// static
void H264SPS::GetLevelConfigFromProfileLevel(VideoCodecProfile profile,
uint8_t level,
int* level_idc,
bool* constraint_set3_flag) {
// Spec A.3.1.
// Note: we always use h264_output_level = 9 to indicate Level 1b in
// VideoEncodeAccelerator::Config, in order to tell apart from Level 1.1
// which level IDC is also 11.
// For Baseline and Main profile, if requested level is Level 1b, set
// level_idc to 11 and constraint_set3_flag to true. Otherwise, set level_idc
// to 9 for Level 1b, and ten times level number for others.
if ((profile == H264PROFILE_BASELINE || profile == H264PROFILE_MAIN) &&
level == kLevelIDC1B) {
*level_idc = 11;
*constraint_set3_flag = true;
} else {
*level_idc = level;
}
}
H264SPS::H264SPS() {
memset(this, 0, sizeof(*this));
}
H264SPS& H264SPS::operator=(const H264SPS&) = default;
H264SPS::H264SPS(H264SPS&&) noexcept = default;
// Based on T-REC-H.264 7.4.2.1.1, "Sequence parameter set data semantics",
// available from http://www.itu.int/rec/T-REC-H.264.
std::optional<gfx::Size> H264SPS::GetCodedSize() const {
// Interlaced frames are twice the height of each field.
const int mb_unit = 16;
int map_unit = frame_mbs_only_flag ? 16 : 32;
// Verify that the values are not too large before multiplying them.
// TODO(sandersd): These limits could be much smaller. The currently-largest
// specified limit (excluding SVC, multiview, etc., which I didn't bother to
// read) is 543 macroblocks (section A.3.1).
int max_mb_minus1 = std::numeric_limits<int>::max() / mb_unit - 1;
int max_map_units_minus1 = std::numeric_limits<int>::max() / map_unit - 1;
if (pic_width_in_mbs_minus1 > max_mb_minus1 ||
pic_height_in_map_units_minus1 > max_map_units_minus1) {
DVLOG(1) << "Coded size is too large.";
return std::nullopt;
}
return gfx::Size(mb_unit * (pic_width_in_mbs_minus1 + 1),
map_unit * (pic_height_in_map_units_minus1 + 1));
}
// Also based on section 7.4.2.1.1.
std::optional<gfx::Rect> H264SPS::GetVisibleRect() const {
std::optional<gfx::Size> coded_size = GetCodedSize();
if (!coded_size)
return std::nullopt;
if (!frame_cropping_flag)
return gfx::Rect(coded_size.value());
int crop_unit_x;
int crop_unit_y;
if (chroma_array_type == 0) {
crop_unit_x = 1;
crop_unit_y = frame_mbs_only_flag ? 1 : 2;
} else {
// Section 6.2.
// |chroma_format_idc| may be:
// 1 => 4:2:0
// 2 => 4:2:2
// 3 => 4:4:4
// Everything else has |chroma_array_type| == 0.
int sub_width_c = chroma_format_idc > 2 ? 1 : 2;
int sub_height_c = chroma_format_idc > 1 ? 1 : 2;
crop_unit_x = sub_width_c;
crop_unit_y = sub_height_c * (frame_mbs_only_flag ? 1 : 2);
}
// Verify that the values are not too large before multiplying.
if (coded_size->width() / crop_unit_x < frame_crop_left_offset ||
coded_size->width() / crop_unit_x < frame_crop_right_offset ||
coded_size->height() / crop_unit_y < frame_crop_top_offset ||
coded_size->height() / crop_unit_y < frame_crop_bottom_offset) {
DVLOG(1) << "Frame cropping exceeds coded size.";
return std::nullopt;
}
int crop_left = crop_unit_x * frame_crop_left_offset;
int crop_right = crop_unit_x * frame_crop_right_offset;
int crop_top = crop_unit_y * frame_crop_top_offset;
int crop_bottom = crop_unit_y * frame_crop_bottom_offset;
// Verify that the values are sane. Note that some decoders also require that
// crops are smaller than a macroblock and/or that crops must be adjacent to
// at least one corner of the coded frame.
if (coded_size->width() - crop_left <= crop_right ||
coded_size->height() - crop_top <= crop_bottom) {
DVLOG(1) << "Frame cropping excludes entire frame.";
return std::nullopt;
}
return gfx::Rect(crop_left, crop_top,
coded_size->width() - crop_left - crop_right,
coded_size->height() - crop_top - crop_bottom);
}
// Based on T-REC-H.264 E.2.1, "VUI parameters semantics",
// available from http://www.itu.int/rec/T-REC-H.264.
VideoColorSpace H264SPS::GetColorSpace() const {
if (colour_description_present_flag) {
return VideoColorSpace(
colour_primaries, transfer_characteristics, matrix_coefficients,
video_full_range_flag ? gfx::ColorSpace::RangeID::FULL
: gfx::ColorSpace::RangeID::LIMITED);
} else {
return VideoColorSpace();
}
}
VideoChromaSampling H264SPS::GetChromaSampling() const {
// Spec section 6.2
switch (chroma_format_idc) {
case 0:
return VideoChromaSampling::k400;
case 1:
return VideoChromaSampling::k420;
case 2:
return VideoChromaSampling::k422;
case 3:
return VideoChromaSampling::k444;
default:
DVLOG(1) << "Unknown chroma subsampling format.";
return VideoChromaSampling::kUnknown;
}
}
uint8_t H264SPS::GetIndicatedLevel() const {
// Spec A.3.1 and A.3.2
// For Baseline, Constrained Baseline and Main profile, the indicated level is
// Level 1b if level_idc is equal to 11 and constraint_set3_flag is true.
if ((profile_idc == H264SPS::kProfileIDCBaseline ||
profile_idc == H264SPS::kProfileIDCConstrainedBaseline ||
profile_idc == H264SPS::kProfileIDCMain) &&
level_idc == 11 && constraint_set3_flag) {
return kLevelIDC1B; // Level 1b
}
// Otherwise, the level_idc is equal to 9 for Level 1b, and others are equal
// to values of ten times the level numbers.
return base::checked_cast<uint8_t>(level_idc);
}
bool H264SPS::CheckIndicatedLevelWithinTarget(uint8_t target_level) const {
// See table A-1 in spec.
// Level 1.0 < 1b < 1.1 < 1.2 .... (in numeric order).
uint8_t level = GetIndicatedLevel();
if (target_level == kLevelIDC1p0)
return level == kLevelIDC1p0;
if (target_level == kLevelIDC1B)
return level == kLevelIDC1p0 || level == kLevelIDC1B;
return level <= target_level;
}
H264PPS::H264PPS() {
memset(this, 0, sizeof(*this));
}
H264PPS::H264PPS(H264PPS&&) noexcept = default;
H264SliceHeader::H264SliceHeader() {
memset(this, 0, sizeof(*this));
}
H264SliceHeader::H264SliceHeader(const H264SliceHeader& t) = default;
H264SliceHeader& H264SliceHeader::operator=(const H264SliceHeader& t) = default;
H264SEIMessage::H264SEIMessage() {
memset(this, 0, sizeof(*this));
}
gfx::HdrMetadataCta861_3 H264SEIContentLightLevelInfo::ToGfx() const {
return gfx::HdrMetadataCta861_3(max_content_light_level,
max_picture_average_light_level);
}
gfx::HdrMetadataSmpteSt2086 H264SEIMasteringDisplayInfo::ToGfx() const {
constexpr auto kChromaDenominator = 50000.0f;
constexpr auto kLumaDenoninator = 10000.0f;
// display primaries are in G/B/R order in MDCV SEI.
return gfx::HdrMetadataSmpteSt2086(
{display_primaries[2][0] / kChromaDenominator,
display_primaries[2][1] / kChromaDenominator,
display_primaries[0][0] / kChromaDenominator,
display_primaries[0][1] / kChromaDenominator,
display_primaries[1][0] / kChromaDenominator,
display_primaries[1][1] / kChromaDenominator,
white_points[0] / kChromaDenominator,
white_points[1] / kChromaDenominator},
/*luminance_max=*/max_luminance / kLumaDenoninator,
/*luminance_min=*/min_luminance / kLumaDenoninator);
}
H264SEI::H264SEI() = default;
H264SEI::~H264SEI() = default;
// ISO 14496 part 10
// VUI parameters: Table E-1 "Meaning of sample aspect ratio indicator"
static const int kTableSarWidth[] = {0, 1, 12, 10, 16, 40, 24, 20, 32,
80, 18, 15, 64, 160, 4, 3, 2};
static const int kTableSarHeight[] = {0, 1, 11, 11, 11, 33, 11, 11, 11,
33, 11, 11, 33, 99, 3, 2, 1};
static_assert(std::size(kTableSarWidth) == std::size(kTableSarHeight),
"sar tables must have the same size");
H264Parser::H264Parser() {
Reset();
}
H264Parser::~H264Parser() = default;
void H264Parser::Reset() {
stream_ = nullptr;
bytes_left_ = 0;
encrypted_ranges_.clear();
previous_nalu_range_.clear();
}
void H264Parser::SetStream(const uint8_t* stream, off_t stream_size) {
std::vector<SubsampleEntry> subsamples;
SetEncryptedStream(stream, stream_size, subsamples);
}
void H264Parser::SetEncryptedStream(
const uint8_t* stream,
off_t stream_size,
const std::vector<SubsampleEntry>& subsamples) {
DCHECK(stream);
DCHECK_GT(stream_size, 0);
stream_ = stream;
bytes_left_ = stream_size;
previous_nalu_range_.clear();
encrypted_ranges_.clear();
const uint8_t* start = stream;
const uint8_t* stream_end = stream_ + bytes_left_;
for (size_t i = 0; i < subsamples.size() && start < stream_end; ++i) {
start += subsamples[i].clear_bytes;
const uint8_t* end =
std::min(start + subsamples[i].cypher_bytes, stream_end);
encrypted_ranges_.Add(start, end);
start = end;
}
}
const H264PPS* H264Parser::GetPPS(int pps_id) const {
auto it = active_PPSes_.find(pps_id);
if (it == active_PPSes_.end()) {
DVLOG(1) << "Requested a nonexistent PPS id " << pps_id;
return nullptr;
}
return it->second.get();
}
const H264SPS* H264Parser::GetSPS(int sps_id) const {
auto it = active_SPSes_.find(sps_id);
if (it == active_SPSes_.end()) {
DVLOG(1) << "Requested a nonexistent SPS id " << sps_id;
return nullptr;
}
return it->second.get();
}
static inline bool IsStartCode(const uint8_t* data) {
return data[0] == 0x00 && data[1] == 0x00 && data[2] == 0x01;
}
// static
bool H264Parser::FindStartCode(const uint8_t* data,
off_t data_size,
off_t* offset,
off_t* start_code_size) {
DCHECK_GE(data_size, 0);
off_t bytes_left = data_size;
while (bytes_left >= 3) {
// The start code is "\0\0\1", ones are more unusual than zeroes, so let's
// search for it first.
const uint8_t* tmp =
reinterpret_cast<const uint8_t*>(memchr(data + 2, 1, bytes_left - 2));
if (!tmp) {
data += bytes_left - 2;
bytes_left = 2;
break;
}
tmp -= 2;
bytes_left -= tmp - data;
data = tmp;
if (IsStartCode(data)) {
// Found three-byte start code, set pointer at its beginning.
*offset = data_size - bytes_left;
*start_code_size = 3;
// If there is a zero byte before this start code,
// then it's actually a four-byte start code, so backtrack one byte.
if (*offset > 0 && *(data - 1) == 0x00) {
--(*offset);
++(*start_code_size);
}
return true;
}
++data;
--bytes_left;
}
// End of data: offset is pointing to the first byte that was not considered
// as a possible start of a start code.
// Note: there is no security issue when receiving a negative |data_size|
// since in this case, |bytes_left| is equal to |data_size| and thus
// |*offset| is equal to 0 (valid offset).
*offset = data_size - bytes_left;
*start_code_size = 0;
return false;
}
bool H264Parser::LocateNALU(off_t* nalu_size, off_t* start_code_size) {
// Find the start code of next NALU.
off_t nalu_start_off = 0;
off_t annexb_start_code_size = 0;
if (!FindStartCodeInClearRanges(stream_, bytes_left_, encrypted_ranges_,
&nalu_start_off, &annexb_start_code_size)) {
DVLOG(4) << "Could not find start code, end of stream?";
return false;
}
// Move the stream to the beginning of the NALU (pointing at the start code).
stream_ += nalu_start_off;
bytes_left_ -= nalu_start_off;
const uint8_t* nalu_data = stream_ + annexb_start_code_size;
off_t max_nalu_data_size = bytes_left_ - annexb_start_code_size;
if (max_nalu_data_size <= 0) {
DVLOG(3) << "End of stream";
return false;
}
// Find the start code of next NALU;
// if successful, |nalu_size_without_start_code| is the number of bytes from
// after previous start code to before this one;
// if next start code is not found, it is still a valid NALU since there
// are some bytes left after the first start code: all the remaining bytes
// belong to the current NALU.
off_t next_start_code_size = 0;
off_t nalu_size_without_start_code = 0;
if (!FindStartCodeInClearRanges(
nalu_data, max_nalu_data_size, encrypted_ranges_,
&nalu_size_without_start_code, &next_start_code_size)) {
nalu_size_without_start_code = max_nalu_data_size;
}
*nalu_size = nalu_size_without_start_code + annexb_start_code_size;
*start_code_size = annexb_start_code_size;
return true;
}
// static
bool H264Parser::FindStartCodeInClearRanges(
const uint8_t* data,
off_t data_size,
const Ranges<const uint8_t*>& encrypted_ranges,
off_t* offset,
off_t* start_code_size) {
if (encrypted_ranges.size() == 0)
return FindStartCode(data, data_size, offset, start_code_size);
DCHECK_GE(data_size, 0);
const uint8_t* start = data;
do {
off_t bytes_left = data_size - (start - data);
if (!FindStartCode(start, bytes_left, offset, start_code_size))
return false;
// Construct a Ranges object that represents the region occupied
// by the start code and the 1 byte needed to read the NAL unit type.
const uint8_t* start_code = start + *offset;
const uint8_t* start_code_end = start_code + *start_code_size;
Ranges<const uint8_t*> start_code_range;
start_code_range.Add(start_code, start_code_end + 1);
if (encrypted_ranges.IntersectionWith(start_code_range).size() > 0) {
// The start code is inside an encrypted section so we need to scan
// for another start code.
*start_code_size = 0;
start += std::min(*offset + 1, bytes_left);
}
} while (*start_code_size == 0);
// Update |*offset| to include the data we skipped over.
*offset += start - data;
return true;
}
// static
VideoCodecProfile H264Parser::ProfileIDCToVideoCodecProfile(int profile_idc) {
switch (profile_idc) {
case H264SPS::kProfileIDCBaseline:
return H264PROFILE_BASELINE;
case H264SPS::kProfileIDCMain:
return H264PROFILE_MAIN;
case H264SPS::kProfileIDCHigh:
return H264PROFILE_HIGH;
case H264SPS::kProfileIDHigh10:
return H264PROFILE_HIGH10PROFILE;
case H264SPS::kProfileIDHigh422:
return H264PROFILE_HIGH422PROFILE;
case H264SPS::kProfileIDHigh444Predictive:
return H264PROFILE_HIGH444PREDICTIVEPROFILE;
case H264SPS::kProfileIDScalableBaseline:
return H264PROFILE_SCALABLEBASELINE;
case H264SPS::kProfileIDScalableHigh:
return H264PROFILE_SCALABLEHIGH;
case H264SPS::kProfileIDStereoHigh:
return H264PROFILE_STEREOHIGH;
case H264SPS::kProfileIDSMultiviewHigh:
return H264PROFILE_MULTIVIEWHIGH;
}
DVLOG(1) << "unknown video profile: " << profile_idc;
return VIDEO_CODEC_PROFILE_UNKNOWN;
}
// static
bool H264Parser::ParseNALUs(const uint8_t* stream,
size_t stream_size,
std::vector<H264NALU>* nalus) {
DCHECK(nalus);
H264Parser parser;
parser.SetStream(stream, stream_size);
while (true) {
H264NALU nalu;
const H264Parser::Result result = parser.AdvanceToNextNALU(&nalu);
if (result == H264Parser::kOk) {
nalus->push_back(nalu);
} else if (result == media::H264Parser::kEOStream) {
return true;
} else {
DLOG(ERROR) << "Unexpected H264 parser result";
return false;
}
}
NOTREACHED_NORETURN();
}
H264Parser::Result H264Parser::AdvanceToNextNALU(H264NALU* nalu) {
off_t start_code_size;
off_t nalu_size_with_start_code;
if (!LocateNALU(&nalu_size_with_start_code, &start_code_size)) {
DVLOG(4) << "Could not find next NALU, bytes left in stream: "
<< bytes_left_;
stream_ = nullptr;
bytes_left_ = 0;
return kEOStream;
}
nalu->data = stream_ + start_code_size;
nalu->size = nalu_size_with_start_code - start_code_size;
DVLOG(4) << "NALU found: size=" << nalu_size_with_start_code;
// Initialize bit reader at the start of found NALU.
if (!br_.Initialize(nalu->data, nalu->size)) {
stream_ = nullptr;
bytes_left_ = 0;
return kEOStream;
}
// Move parser state to after this NALU, so next time AdvanceToNextNALU
// is called, we will effectively be skipping it;
// other parsing functions will use the position saved
// in bit reader for parsing, so we don't have to remember it here.
stream_ += nalu_size_with_start_code;
bytes_left_ -= nalu_size_with_start_code;
// Read NALU header, skip the forbidden_zero_bit, but check for it.
int data;
READ_BITS_OR_RETURN(1, &data);
TRUE_OR_RETURN(data == 0);
READ_BITS_OR_RETURN(2, &nalu->nal_ref_idc);
READ_BITS_OR_RETURN(5, &nalu->nal_unit_type);
DVLOG(4) << "NALU type: " << static_cast<int>(nalu->nal_unit_type)
<< " at: " << reinterpret_cast<const void*>(nalu->data)
<< " size: " << nalu->size
<< " ref: " << static_cast<int>(nalu->nal_ref_idc);
previous_nalu_range_.clear();
previous_nalu_range_.Add(nalu->data, nalu->data + nalu->size);
return kOk;
}
// Default scaling lists (per spec).
static const uint8_t kDefault4x4Intra[kH264ScalingList4x4Length] = {
6, 13, 13, 20, 20, 20, 28, 28, 28, 28, 32, 32, 32, 37, 37, 42,
};
static const uint8_t kDefault4x4Inter[kH264ScalingList4x4Length] = {
10, 14, 14, 20, 20, 20, 24, 24, 24, 24, 27, 27, 27, 30, 30, 34,
};
static const uint8_t kDefault8x8Intra[kH264ScalingList8x8Length] = {
6, 10, 10, 13, 11, 13, 16, 16, 16, 16, 18, 18, 18, 18, 18, 23,
23, 23, 23, 23, 23, 25, 25, 25, 25, 25, 25, 25, 27, 27, 27, 27,
27, 27, 27, 27, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 31,
31, 33, 33, 33, 33, 33, 36, 36, 36, 36, 38, 38, 38, 40, 40, 42,
};
static const uint8_t kDefault8x8Inter[kH264ScalingList8x8Length] = {
9, 13, 13, 15, 13, 15, 17, 17, 17, 17, 19, 19, 19, 19, 19, 21,
21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 24, 24, 24, 24,
24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 27, 27, 27, 27, 27,
27, 28, 28, 28, 28, 28, 30, 30, 30, 30, 32, 32, 32, 33, 33, 35,
};
static inline void DefaultScalingList4x4(
int i,
uint8_t scaling_list4x4[][kH264ScalingList4x4Length]) {
DCHECK_LT(i, 6);
if (i < 3)
memcpy(scaling_list4x4[i], kDefault4x4Intra, sizeof(kDefault4x4Intra));
else if (i < 6)
memcpy(scaling_list4x4[i], kDefault4x4Inter, sizeof(kDefault4x4Inter));
}
static inline void DefaultScalingList8x8(
int i,
uint8_t scaling_list8x8[][kH264ScalingList8x8Length]) {
DCHECK_LT(i, 6);
if (i % 2 == 0)
memcpy(scaling_list8x8[i], kDefault8x8Intra, sizeof(kDefault8x8Intra));
else
memcpy(scaling_list8x8[i], kDefault8x8Inter, sizeof(kDefault8x8Inter));
}
static void FallbackScalingList4x4(
int i,
const uint8_t default_scaling_list_intra[],
const uint8_t default_scaling_list_inter[],
uint8_t scaling_list4x4[][kH264ScalingList4x4Length]) {
static const int kScalingList4x4ByteSize =
sizeof(scaling_list4x4[0][0]) * kH264ScalingList4x4Length;
switch (i) {
case 0:
memcpy(scaling_list4x4[i], default_scaling_list_intra,
kScalingList4x4ByteSize);
break;
case 1:
memcpy(scaling_list4x4[i], scaling_list4x4[0], kScalingList4x4ByteSize);
break;
case 2:
memcpy(scaling_list4x4[i], scaling_list4x4[1], kScalingList4x4ByteSize);
break;
case 3:
memcpy(scaling_list4x4[i], default_scaling_list_inter,
kScalingList4x4ByteSize);
break;
case 4:
memcpy(scaling_list4x4[i], scaling_list4x4[3], kScalingList4x4ByteSize);
break;
case 5:
memcpy(scaling_list4x4[i], scaling_list4x4[4], kScalingList4x4ByteSize);
break;
default:
NOTREACHED();
break;
}
}
static void FallbackScalingList8x8(
int i,
const uint8_t default_scaling_list_intra[],
const uint8_t default_scaling_list_inter[],
uint8_t scaling_list8x8[][kH264ScalingList8x8Length]) {
static const int kScalingList8x8ByteSize =
sizeof(scaling_list8x8[0][0]) * kH264ScalingList8x8Length;
switch (i) {
case 0:
memcpy(scaling_list8x8[i], default_scaling_list_intra,
kScalingList8x8ByteSize);
break;
case 1:
memcpy(scaling_list8x8[i], default_scaling_list_inter,
kScalingList8x8ByteSize);
break;
case 2:
memcpy(scaling_list8x8[i], scaling_list8x8[0], kScalingList8x8ByteSize);
break;
case 3:
memcpy(scaling_list8x8[i], scaling_list8x8[1], kScalingList8x8ByteSize);
break;
case 4:
memcpy(scaling_list8x8[i], scaling_list8x8[2], kScalingList8x8ByteSize);
break;
case 5:
memcpy(scaling_list8x8[i], scaling_list8x8[3], kScalingList8x8ByteSize);
break;
default:
NOTREACHED();
break;
}
}
H264Parser::Result H264Parser::ParseScalingList(int size,
uint8_t* scaling_list,
bool* use_default) {
// See chapter 7.3.2.1.1.1.
int last_scale = 8;
int next_scale = 8;
int delta_scale;
*use_default = false;
for (int j = 0; j < size; ++j) {
if (next_scale != 0) {
READ_SE_OR_RETURN(&delta_scale);
IN_RANGE_OR_RETURN(delta_scale, -128, 127);
next_scale = (last_scale + delta_scale + 256) & 0xff;
if (j == 0 && next_scale == 0) {
*use_default = true;
return kOk;
}
}
scaling_list[j] = (next_scale == 0) ? last_scale : next_scale;
last_scale = scaling_list[j];
}
return kOk;
}
H264Parser::Result H264Parser::ParseSPSScalingLists(H264SPS* sps) {
// See 7.4.2.1.1.
bool seq_scaling_list_present_flag;
bool use_default;
Result res;
// Parse scaling_list4x4.
for (int i = 0; i < 6; ++i) {
READ_BOOL_OR_RETURN(&seq_scaling_list_present_flag);
if (seq_scaling_list_present_flag) {
res = ParseScalingList(std::size(sps->scaling_list4x4[i]),
sps->scaling_list4x4[i], &use_default);
if (res != kOk)
return res;
if (use_default)
DefaultScalingList4x4(i, sps->scaling_list4x4);
} else {
FallbackScalingList4x4(i, kDefault4x4Intra, kDefault4x4Inter,
sps->scaling_list4x4);
}
}
// Parse scaling_list8x8.
for (int i = 0; i < ((sps->chroma_format_idc != 3) ? 2 : 6); ++i) {
READ_BOOL_OR_RETURN(&seq_scaling_list_present_flag);
if (seq_scaling_list_present_flag) {
res = ParseScalingList(std::size(sps->scaling_list8x8[i]),
sps->scaling_list8x8[i], &use_default);
if (res != kOk)
return res;
if (use_default)
DefaultScalingList8x8(i, sps->scaling_list8x8);
} else {
FallbackScalingList8x8(i, kDefault8x8Intra, kDefault8x8Inter,
sps->scaling_list8x8);
}
}
return kOk;
}
H264Parser::Result H264Parser::ParsePPSScalingLists(const H264SPS& sps,
H264PPS* pps) {
// See 7.4.2.2.
bool pic_scaling_list_present_flag;
bool use_default;
Result res;
for (int i = 0; i < 6; ++i) {
READ_BOOL_OR_RETURN(&pic_scaling_list_present_flag);
if (pic_scaling_list_present_flag) {
res = ParseScalingList(std::size(pps->scaling_list4x4[i]),
pps->scaling_list4x4[i], &use_default);
if (res != kOk)
return res;
if (use_default)
DefaultScalingList4x4(i, pps->scaling_list4x4);
} else {
if (!sps.seq_scaling_matrix_present_flag) {
// Table 7-2 fallback rule A in spec.
FallbackScalingList4x4(i, kDefault4x4Intra, kDefault4x4Inter,
pps->scaling_list4x4);
} else {
// Table 7-2 fallback rule B in spec.
FallbackScalingList4x4(i, sps.scaling_list4x4[0],
sps.scaling_list4x4[3], pps->scaling_list4x4);
}
}
}
if (pps->transform_8x8_mode_flag) {
for (int i = 0; i < ((sps.chroma_format_idc != 3) ? 2 : 6); ++i) {
READ_BOOL_OR_RETURN(&pic_scaling_list_present_flag);
if (pic_scaling_list_present_flag) {
res = ParseScalingList(std::size(pps->scaling_list8x8[i]),
pps->scaling_list8x8[i], &use_default);
if (res != kOk)
return res;
if (use_default)
DefaultScalingList8x8(i, pps->scaling_list8x8);
} else {
if (!sps.seq_scaling_matrix_present_flag) {
// Table 7-2 fallback rule A in spec.
FallbackScalingList8x8(i, kDefault8x8Intra, kDefault8x8Inter,
pps->scaling_list8x8);
} else {
// Table 7-2 fallback rule B in spec.
FallbackScalingList8x8(i, sps.scaling_list8x8[0],
sps.scaling_list8x8[1], pps->scaling_list8x8);
}
}
}
}
return kOk;
}
H264Parser::Result H264Parser::ParseAndIgnoreHRDParameters(
bool* hrd_parameters_present) {
int data;
READ_BOOL_OR_RETURN(&data); // {nal,vcl}_hrd_parameters_present_flag
if (!data)
return kOk;
*hrd_parameters_present = true;
int cpb_cnt_minus1;
READ_UE_OR_RETURN(&cpb_cnt_minus1);
IN_RANGE_OR_RETURN(cpb_cnt_minus1, 0, 31);
READ_BITS_OR_RETURN(8, &data); // bit_rate_scale, cpb_size_scale
for (int i = 0; i <= cpb_cnt_minus1; ++i) {
READ_UE_OR_RETURN(&data); // bit_rate_value_minus1[i]
READ_UE_OR_RETURN(&data); // cpb_size_value_minus1[i]
READ_BOOL_OR_RETURN(&data); // cbr_flag
}
READ_BITS_OR_RETURN(20, &data); // cpb/dpb delays, etc.
return kOk;
}
H264Parser::Result H264Parser::ParseVUIParameters(H264SPS* sps) {
bool aspect_ratio_info_present_flag;
READ_BOOL_OR_RETURN(&aspect_ratio_info_present_flag);
if (aspect_ratio_info_present_flag) {
int aspect_ratio_idc;
READ_BITS_OR_RETURN(8, &aspect_ratio_idc);
if (aspect_ratio_idc == H264SPS::kExtendedSar) {
READ_BITS_OR_RETURN(16, &sps->sar_width);
READ_BITS_OR_RETURN(16, &sps->sar_height);
} else {
const int max_aspect_ratio_idc = std::size(kTableSarWidth) - 1;
IN_RANGE_OR_RETURN(aspect_ratio_idc, 0, max_aspect_ratio_idc);
sps->sar_width = kTableSarWidth[aspect_ratio_idc];
sps->sar_height = kTableSarHeight[aspect_ratio_idc];
}
}
int data;
// Read and ignore overscan and video signal type info.
READ_BOOL_OR_RETURN(&data); // overscan_info_present_flag
if (data)
READ_BOOL_OR_RETURN(&data); // overscan_appropriate_flag
READ_BOOL_OR_RETURN(&sps->video_signal_type_present_flag);
if (sps->video_signal_type_present_flag) {
READ_BITS_OR_RETURN(3, &sps->video_format);
READ_BOOL_OR_RETURN(&sps->video_full_range_flag);
READ_BOOL_OR_RETURN(&sps->colour_description_present_flag);
if (sps->colour_description_present_flag) {
// color description syntax elements
READ_BITS_OR_RETURN(8, &sps->colour_primaries);
READ_BITS_OR_RETURN(8, &sps->transfer_characteristics);
READ_BITS_OR_RETURN(8, &sps->matrix_coefficients);
}
}
READ_BOOL_OR_RETURN(&data); // chroma_loc_info_present_flag
if (data) {
READ_UE_OR_RETURN(&data); // chroma_sample_loc_type_top_field
READ_UE_OR_RETURN(&data); // chroma_sample_loc_type_bottom_field
}
// Read and ignore timing info.
READ_BOOL_OR_RETURN(&data); // timing_info_present_flag
if (data) {
READ_BITS_OR_RETURN(16, &data); // num_units_in_tick
READ_BITS_OR_RETURN(16, &data); // num_units_in_tick
READ_BITS_OR_RETURN(16, &data); // time_scale
READ_BITS_OR_RETURN(16, &data); // time_scale
READ_BOOL_OR_RETURN(&data); // fixed_frame_rate_flag
}
// Read and ignore NAL HRD parameters, if present.
bool hrd_parameters_present = false;
Result res = ParseAndIgnoreHRDParameters(&hrd_parameters_present);
if (res != kOk)
return res;
// Read and ignore VCL HRD parameters, if present.
res = ParseAndIgnoreHRDParameters(&hrd_parameters_present);
if (res != kOk)
return res;
if (hrd_parameters_present) // One of NAL or VCL params present is enough.
READ_BOOL_OR_RETURN(&data); // low_delay_hrd_flag
READ_BOOL_OR_RETURN(&data); // pic_struct_present_flag
READ_BOOL_OR_RETURN(&sps->bitstream_restriction_flag);
if (sps->bitstream_restriction_flag) {
READ_BOOL_OR_RETURN(&data); // motion_vectors_over_pic_boundaries_flag
READ_UE_OR_RETURN(&data); // max_bytes_per_pic_denom
READ_UE_OR_RETURN(&data); // max_bits_per_mb_denom
READ_UE_OR_RETURN(&data); // log2_max_mv_length_horizontal
READ_UE_OR_RETURN(&data); // log2_max_mv_length_vertical
READ_UE_OR_RETURN(&sps->max_num_reorder_frames);
READ_UE_OR_RETURN(&sps->max_dec_frame_buffering);
TRUE_OR_RETURN(sps->max_dec_frame_buffering >= sps->max_num_ref_frames);
IN_RANGE_OR_RETURN(sps->max_num_reorder_frames, 0,
sps->max_dec_frame_buffering);
}
return kOk;
}
static void FillDefaultSeqScalingLists(H264SPS* sps) {
static_assert(sizeof(sps->scaling_list4x4[0][0]) == sizeof(uint8_t));
memset(sps->scaling_list4x4, 16, sizeof(sps->scaling_list4x4));
static_assert(sizeof(sps->scaling_list8x8[0][0]) == sizeof(uint8_t));
memset(sps->scaling_list8x8, 16, sizeof(sps->scaling_list8x8));
}
H264Parser::Result H264Parser::ParseSPS(int* sps_id) {
// See 7.4.2.1.
int data;
Result res;
*sps_id = -1;
std::unique_ptr<H264SPS> sps(new H264SPS());
READ_BITS_OR_RETURN(8, &sps->profile_idc);
READ_BOOL_OR_RETURN(&sps->constraint_set0_flag);
READ_BOOL_OR_RETURN(&sps->constraint_set1_flag);
READ_BOOL_OR_RETURN(&sps->constraint_set2_flag);
READ_BOOL_OR_RETURN(&sps->constraint_set3_flag);
READ_BOOL_OR_RETURN(&sps->constraint_set4_flag);
READ_BOOL_OR_RETURN(&sps->constraint_set5_flag);
READ_BITS_OR_RETURN(2, &data); // reserved_zero_2bits
READ_BITS_OR_RETURN(8, &sps->level_idc);
READ_UE_OR_RETURN(&sps->seq_parameter_set_id);
TRUE_OR_RETURN(sps->seq_parameter_set_id < 32);
if (sps->profile_idc == 100 || sps->profile_idc == 110 ||
sps->profile_idc == 122 || sps->profile_idc == 244 ||
sps->profile_idc == 44 || sps->profile_idc == 83 ||
sps->profile_idc == 86 || sps->profile_idc == 118 ||
sps->profile_idc == 128) {
READ_UE_OR_RETURN(&sps->chroma_format_idc);
TRUE_OR_RETURN(sps->chroma_format_idc < 4);
if (sps->chroma_format_idc == 3)
READ_BOOL_OR_RETURN(&sps->separate_colour_plane_flag);
READ_UE_OR_RETURN(&sps->bit_depth_luma_minus8);
TRUE_OR_RETURN(sps->bit_depth_luma_minus8 < 7);
READ_UE_OR_RETURN(&sps->bit_depth_chroma_minus8);
TRUE_OR_RETURN(sps->bit_depth_chroma_minus8 < 7);
READ_BOOL_OR_RETURN(&sps->qpprime_y_zero_transform_bypass_flag);
READ_BOOL_OR_RETURN(&sps->seq_scaling_matrix_present_flag);
if (sps->seq_scaling_matrix_present_flag) {
DVLOG(4) << "Scaling matrix present";
res = ParseSPSScalingLists(sps.get());
if (res != kOk)
return res;
} else {
FillDefaultSeqScalingLists(sps.get());
}
} else {
sps->chroma_format_idc = 1;
FillDefaultSeqScalingLists(sps.get());
}
if (sps->separate_colour_plane_flag)
sps->chroma_array_type = 0;
else
sps->chroma_array_type = sps->chroma_format_idc;
READ_UE_OR_RETURN(&sps->log2_max_frame_num_minus4);
TRUE_OR_RETURN(sps->log2_max_frame_num_minus4 < 13);
READ_UE_OR_RETURN(&sps->pic_order_cnt_type);
TRUE_OR_RETURN(sps->pic_order_cnt_type < 3);
if (sps->pic_order_cnt_type == 0) {
READ_UE_OR_RETURN(&sps->log2_max_pic_order_cnt_lsb_minus4);
TRUE_OR_RETURN(sps->log2_max_pic_order_cnt_lsb_minus4 < 13);
sps->expected_delta_per_pic_order_cnt_cycle = 0;
} else if (sps->pic_order_cnt_type == 1) {
READ_BOOL_OR_RETURN(&sps->delta_pic_order_always_zero_flag);
READ_SE_OR_RETURN(&sps->offset_for_non_ref_pic);
READ_SE_OR_RETURN(&sps->offset_for_top_to_bottom_field);
READ_UE_OR_RETURN(&sps->num_ref_frames_in_pic_order_cnt_cycle);
TRUE_OR_RETURN(sps->num_ref_frames_in_pic_order_cnt_cycle < 255);
base::CheckedNumeric<int> offset_acc = 0;
for (int i = 0; i < sps->num_ref_frames_in_pic_order_cnt_cycle; ++i) {
READ_SE_OR_RETURN(&sps->offset_for_ref_frame[i]);
offset_acc += sps->offset_for_ref_frame[i];
}
if (!offset_acc.IsValid())
return kInvalidStream;
sps->expected_delta_per_pic_order_cnt_cycle = offset_acc.ValueOrDefault(0);
}
READ_UE_OR_RETURN(&sps->max_num_ref_frames);
READ_BOOL_OR_RETURN(&sps->gaps_in_frame_num_value_allowed_flag);
READ_UE_OR_RETURN(&sps->pic_width_in_mbs_minus1);
READ_UE_OR_RETURN(&sps->pic_height_in_map_units_minus1);
READ_BOOL_OR_RETURN(&sps->frame_mbs_only_flag);
if (!sps->frame_mbs_only_flag)
READ_BOOL_OR_RETURN(&sps->mb_adaptive_frame_field_flag);
READ_BOOL_OR_RETURN(&sps->direct_8x8_inference_flag);
READ_BOOL_OR_RETURN(&sps->frame_cropping_flag);
if (sps->frame_cropping_flag) {
READ_UE_OR_RETURN(&sps->frame_crop_left_offset);
READ_UE_OR_RETURN(&sps->frame_crop_right_offset);
READ_UE_OR_RETURN(&sps->frame_crop_top_offset);
READ_UE_OR_RETURN(&sps->frame_crop_bottom_offset);
}
READ_BOOL_OR_RETURN(&sps->vui_parameters_present_flag);
if (sps->vui_parameters_present_flag) {
DVLOG(4) << "VUI parameters present";
res = ParseVUIParameters(sps.get());
if (res != kOk)
return res;
}
// If an SPS with the same id already exists, replace it.
*sps_id = sps->seq_parameter_set_id;
active_SPSes_[*sps_id] = std::move(sps);
return kOk;
}
H264Parser::Result H264Parser::ParsePPS(int* pps_id) {
// See 7.4.2.2.
const H264SPS* sps;
Result res;
*pps_id = -1;
std::unique_ptr<H264PPS> pps(new H264PPS());
READ_UE_OR_RETURN(&pps->pic_parameter_set_id);
READ_UE_OR_RETURN(&pps->seq_parameter_set_id);
TRUE_OR_RETURN(pps->seq_parameter_set_id < 32);
if (active_SPSes_.find(pps->seq_parameter_set_id) == active_SPSes_.end()) {
DVLOG(1) << "Invalid stream, no SPS id: " << pps->seq_parameter_set_id;
return kInvalidStream;
}
sps = GetSPS(pps->seq_parameter_set_id);
TRUE_OR_RETURN(sps);
READ_BOOL_OR_RETURN(&pps->entropy_coding_mode_flag);
READ_BOOL_OR_RETURN(&pps->bottom_field_pic_order_in_frame_present_flag);
READ_UE_OR_RETURN(&pps->num_slice_groups_minus1);
if (pps->num_slice_groups_minus1 > 1) {
DVLOG(1) << "Slice groups not supported";
return kUnsupportedStream;
}
READ_UE_OR_RETURN(&pps->num_ref_idx_l0_default_active_minus1);
TRUE_OR_RETURN(pps->num_ref_idx_l0_default_active_minus1 < 32);
READ_UE_OR_RETURN(&pps->num_ref_idx_l1_default_active_minus1);
TRUE_OR_RETURN(pps->num_ref_idx_l1_default_active_minus1 < 32);
READ_BOOL_OR_RETURN(&pps->weighted_pred_flag);
READ_BITS_OR_RETURN(2, &pps->weighted_bipred_idc);
TRUE_OR_RETURN(pps->weighted_bipred_idc < 3);
READ_SE_OR_RETURN(&pps->pic_init_qp_minus26);
IN_RANGE_OR_RETURN(pps->pic_init_qp_minus26, -26, 25);
READ_SE_OR_RETURN(&pps->pic_init_qs_minus26);
IN_RANGE_OR_RETURN(pps->pic_init_qs_minus26, -26, 25);
READ_SE_OR_RETURN(&pps->chroma_qp_index_offset);
IN_RANGE_OR_RETURN(pps->chroma_qp_index_offset, -12, 12);
pps->second_chroma_qp_index_offset = pps->chroma_qp_index_offset;
READ_BOOL_OR_RETURN(&pps->deblocking_filter_control_present_flag);
READ_BOOL_OR_RETURN(&pps->constrained_intra_pred_flag);
READ_BOOL_OR_RETURN(&pps->redundant_pic_cnt_present_flag);
bool pps_remainder_unencrypted = true;
if (encrypted_ranges_.size()) {
Ranges<const uint8_t*> pps_range;
// Only check that the next byte is unencrypted, not the rest of the NALU.
const uint8_t* next_byte =
previous_nalu_range_.end(0) - br_.NumBitsLeft() / 8;
pps_range.Add(next_byte, next_byte + 1);
pps_remainder_unencrypted =
(encrypted_ranges_.IntersectionWith(pps_range).size() == 0);
}
if (pps_remainder_unencrypted && br_.HasMoreRBSPData()) {
if (sps->profile_idc == H264SPS::kProfileIDCBaseline ||
sps->profile_idc == H264SPS::kProfileIDCConstrainedBaseline ||
sps->profile_idc == H264SPS::kProfileIDCMain) {
DVLOG(1) << "Invalid stream, ignored unexpected RBSB data in PPS frame";
} else {
READ_BOOL_OR_RETURN(&pps->transform_8x8_mode_flag);
READ_BOOL_OR_RETURN(&pps->pic_scaling_matrix_present_flag);
if (pps->pic_scaling_matrix_present_flag) {
DVLOG(4) << "Picture scaling matrix present";
res = ParsePPSScalingLists(*sps, pps.get());
if (res != kOk)
return res;
}
READ_SE_OR_RETURN(&pps->second_chroma_qp_index_offset);
}
}
// If a PPS with the same id already exists, replace it.
*pps_id = pps->pic_parameter_set_id;
active_PPSes_[*pps_id] = std::move(pps);
return kOk;
}
H264Parser::Result H264Parser::ParseSPSExt(int* sps_id) {
// See 7.4.2.1.
int local_sps_id = -1;
*sps_id = -1;
READ_UE_OR_RETURN(&local_sps_id);
TRUE_OR_RETURN(local_sps_id < 32);
*sps_id = local_sps_id;
return kOk;
}
H264Parser::Result H264Parser::ParseRefPicListModification(
int num_ref_idx_active_minus1,
H264ModificationOfPicNum* ref_list_mods) {
H264ModificationOfPicNum* pic_num_mod;
if (num_ref_idx_active_minus1 >= 32)
return kInvalidStream;
for (int i = 0; i < 32; ++i) {
pic_num_mod = &ref_list_mods[i];
READ_UE_OR_RETURN(&pic_num_mod->modification_of_pic_nums_idc);
TRUE_OR_RETURN(pic_num_mod->modification_of_pic_nums_idc < 4);
switch (pic_num_mod->modification_of_pic_nums_idc) {
case 0:
case 1:
READ_UE_OR_RETURN(&pic_num_mod->abs_diff_pic_num_minus1);
break;
case 2:
READ_UE_OR_RETURN(&pic_num_mod->long_term_pic_num);
break;
case 3:
// Per spec, list cannot be empty.
if (i == 0)
return kInvalidStream;
return kOk;
default:
return kInvalidStream;
}
}
// If we got here, we didn't get loop end marker prematurely,
// so make sure it is there for our client.
int modification_of_pic_nums_idc;
READ_UE_OR_RETURN(&modification_of_pic_nums_idc);
TRUE_OR_RETURN(modification_of_pic_nums_idc == 3);
return kOk;
}
H264Parser::Result H264Parser::ParseRefPicListModifications(
H264SliceHeader* shdr) {
Result res;
if (!shdr->IsISlice() && !shdr->IsSISlice()) {
READ_BOOL_OR_RETURN(&shdr->ref_pic_list_modification_flag_l0);
if (shdr->ref_pic_list_modification_flag_l0) {
res = ParseRefPicListModification(shdr->num_ref_idx_l0_active_minus1,
shdr->ref_list_l0_modifications);
if (res != kOk)
return res;
}
}
if (shdr->IsBSlice()) {
READ_BOOL_OR_RETURN(&shdr->ref_pic_list_modification_flag_l1);
if (shdr->ref_pic_list_modification_flag_l1) {
res = ParseRefPicListModification(shdr->num_ref_idx_l1_active_minus1,
shdr->ref_list_l1_modifications);
if (res != kOk)
return res;
}
}
return kOk;
}
H264Parser::Result H264Parser::ParseWeightingFactors(
int num_ref_idx_active_minus1,
int chroma_array_type,
int luma_log2_weight_denom,
int chroma_log2_weight_denom,
H264WeightingFactors* w_facts) {
int def_luma_weight = 1 << luma_log2_weight_denom;
int def_chroma_weight = 1 << chroma_log2_weight_denom;
for (int i = 0; i < num_ref_idx_active_minus1 + 1; ++i) {
READ_BOOL_OR_RETURN(&w_facts->luma_weight_flag);
if (w_facts->luma_weight_flag) {
READ_SE_OR_RETURN(&w_facts->luma_weight[i]);
IN_RANGE_OR_RETURN(w_facts->luma_weight[i], -128, 127);
READ_SE_OR_RETURN(&w_facts->luma_offset[i]);
IN_RANGE_OR_RETURN(w_facts->luma_offset[i], -128, 127);
} else {
w_facts->luma_weight[i] = def_luma_weight;
w_facts->luma_offset[i] = 0;
}
if (chroma_array_type != 0) {
READ_BOOL_OR_RETURN(&w_facts->chroma_weight_flag);
if (w_facts->chroma_weight_flag) {
for (int j = 0; j < 2; ++j) {
READ_SE_OR_RETURN(&w_facts->chroma_weight[i][j]);
IN_RANGE_OR_RETURN(w_facts->chroma_weight[i][j], -128, 127);
READ_SE_OR_RETURN(&w_facts->chroma_offset[i][j]);
IN_RANGE_OR_RETURN(w_facts->chroma_offset[i][j], -128, 127);
}
} else {
for (int j = 0; j < 2; ++j) {
w_facts->chroma_weight[i][j] = def_chroma_weight;
w_facts->chroma_offset[i][j] = 0;
}
}
}
}
return kOk;
}
H264Parser::Result H264Parser::ParsePredWeightTable(const H264SPS& sps,
H264SliceHeader* shdr) {
READ_UE_OR_RETURN(&shdr->luma_log2_weight_denom);
TRUE_OR_RETURN(shdr->luma_log2_weight_denom < 8);
if (sps.chroma_array_type != 0)
READ_UE_OR_RETURN(&shdr->chroma_log2_weight_denom);
TRUE_OR_RETURN(shdr->chroma_log2_weight_denom < 8);
Result res = ParseWeightingFactors(
shdr->num_ref_idx_l0_active_minus1, sps.chroma_array_type,
shdr->luma_log2_weight_denom, shdr->chroma_log2_weight_denom,
&shdr->pred_weight_table_l0);
if (res != kOk)
return res;
if (shdr->IsBSlice()) {
res = ParseWeightingFactors(
shdr->num_ref_idx_l1_active_minus1, sps.chroma_array_type,
shdr->luma_log2_weight_denom, shdr->chroma_log2_weight_denom,
&shdr->pred_weight_table_l1);
if (res != kOk)
return res;
}
return kOk;
}
H264Parser::Result H264Parser::ParseDecRefPicMarking(H264SliceHeader* shdr) {
size_t bits_left_at_start = br_.NumBitsLeft();
if (shdr->idr_pic_flag) {
READ_BOOL_OR_RETURN(&shdr->no_output_of_prior_pics_flag);
READ_BOOL_OR_RETURN(&shdr->long_term_reference_flag);
} else {
READ_BOOL_OR_RETURN(&shdr->adaptive_ref_pic_marking_mode_flag);
H264DecRefPicMarking* marking;
if (shdr->adaptive_ref_pic_marking_mode_flag) {
size_t i;
for (i = 0; i < std::size(shdr->ref_pic_marking); ++i) {
marking = &shdr->ref_pic_marking[i];
READ_UE_OR_RETURN(&marking->memory_mgmnt_control_operation);
if (marking->memory_mgmnt_control_operation == 0)
break;
if (marking->memory_mgmnt_control_operation == 1 ||
marking->memory_mgmnt_control_operation == 3)
READ_UE_OR_RETURN(&marking->difference_of_pic_nums_minus1);
if (marking->memory_mgmnt_control_operation == 2)
READ_UE_OR_RETURN(&marking->long_term_pic_num);
if (marking->memory_mgmnt_control_operation == 3 ||
marking->memory_mgmnt_control_operation == 6)
READ_UE_OR_RETURN(&marking->long_term_frame_idx);
if (marking->memory_mgmnt_control_operation == 4)
READ_UE_OR_RETURN(&marking->max_long_term_frame_idx_plus1);
if (marking->memory_mgmnt_control_operation > 6)
return kInvalidStream;
}
if (i == std::size(shdr->ref_pic_marking)) {
DVLOG(1) << "Ran out of dec ref pic marking fields";
return kUnsupportedStream;
}
}
}
shdr->dec_ref_pic_marking_bit_size = bits_left_at_start - br_.NumBitsLeft();
return kOk;
}
H264Parser::Result H264Parser::ParseSliceHeader(const H264NALU& nalu,
H264SliceHeader* shdr) {
// See 7.4.3.
const H264SPS* sps;
const H264PPS* pps;
Result res;
memset(shdr, 0, sizeof(*shdr));
shdr->idr_pic_flag = (nalu.nal_unit_type == 5);
shdr->nal_ref_idc = nalu.nal_ref_idc;
shdr->nalu_data = nalu.data;
shdr->nalu_size = nalu.size;
READ_UE_OR_RETURN(&shdr->first_mb_in_slice);
READ_UE_OR_RETURN(&shdr->slice_type);
TRUE_OR_RETURN(shdr->slice_type < 10);
READ_UE_OR_RETURN(&shdr->pic_parameter_set_id);
pps = GetPPS(shdr->pic_parameter_set_id);
TRUE_OR_RETURN(pps);
sps = GetSPS(pps->seq_parameter_set_id);
TRUE_OR_RETURN(sps);
if (sps->separate_colour_plane_flag) {
DVLOG(1) << "Interlaced streams not supported";
return kUnsupportedStream;
}
READ_BITS_OR_RETURN(sps->log2_max_frame_num_minus4 + 4, &shdr->frame_num);
if (!sps->frame_mbs_only_flag) {
READ_BOOL_OR_RETURN(&shdr->field_pic_flag);
if (shdr->field_pic_flag) {
DVLOG(1) << "Interlaced streams not supported";
return kUnsupportedStream;
}
}
if (shdr->idr_pic_flag)
READ_UE_OR_RETURN(&shdr->idr_pic_id);
size_t bits_left_at_pic_order_cnt_start = br_.NumBitsLeft();
if (sps->pic_order_cnt_type == 0) {
READ_BITS_OR_RETURN(sps->log2_max_pic_order_cnt_lsb_minus4 + 4,
&shdr->pic_order_cnt_lsb);
if (pps->bottom_field_pic_order_in_frame_present_flag &&
!shdr->field_pic_flag)
READ_SE_OR_RETURN(&shdr->delta_pic_order_cnt_bottom);
}
if (sps->pic_order_cnt_type == 1 && !sps->delta_pic_order_always_zero_flag) {
READ_SE_OR_RETURN(&shdr->delta_pic_order_cnt0);
if (pps->bottom_field_pic_order_in_frame_present_flag &&
!shdr->field_pic_flag)
READ_SE_OR_RETURN(&shdr->delta_pic_order_cnt1);
}
shdr->pic_order_cnt_bit_size =
bits_left_at_pic_order_cnt_start - br_.NumBitsLeft();
if (pps->redundant_pic_cnt_present_flag) {
READ_UE_OR_RETURN(&shdr->redundant_pic_cnt);
TRUE_OR_RETURN(shdr->redundant_pic_cnt < 128);
}
if (shdr->IsBSlice())
READ_BOOL_OR_RETURN(&shdr->direct_spatial_mv_pred_flag);
if (shdr->IsPSlice() || shdr->IsSPSlice() || shdr->IsBSlice()) {
READ_BOOL_OR_RETURN(&shdr->num_ref_idx_active_override_flag);
if (shdr->num_ref_idx_active_override_flag) {
READ_UE_OR_RETURN(&shdr->num_ref_idx_l0_active_minus1);
if (shdr->IsBSlice())
READ_UE_OR_RETURN(&shdr->num_ref_idx_l1_active_minus1);
} else {
shdr->num_ref_idx_l0_active_minus1 =
pps->num_ref_idx_l0_default_active_minus1;
if (shdr->IsBSlice()) {
shdr->num_ref_idx_l1_active_minus1 =
pps->num_ref_idx_l1_default_active_minus1;
}
}
}
if (shdr->field_pic_flag) {
TRUE_OR_RETURN(shdr->num_ref_idx_l0_active_minus1 < 32);
TRUE_OR_RETURN(shdr->num_ref_idx_l1_active_minus1 < 32);
} else {
TRUE_OR_RETURN(shdr->num_ref_idx_l0_active_minus1 < 16);
TRUE_OR_RETURN(shdr->num_ref_idx_l1_active_minus1 < 16);
}
if (nalu.nal_unit_type == H264NALU::kCodedSliceExtension) {
return kUnsupportedStream;
} else {
res = ParseRefPicListModifications(shdr);
if (res != kOk)
return res;
}
if ((pps->weighted_pred_flag && (shdr->IsPSlice() || shdr->IsSPSlice())) ||
(pps->weighted_bipred_idc == 1 && shdr->IsBSlice())) {
res = ParsePredWeightTable(*sps, shdr);
if (res != kOk)
return res;
}
if (nalu.nal_ref_idc != 0) {
res = ParseDecRefPicMarking(shdr);
if (res != kOk)
return res;
}
if (pps->entropy_coding_mode_flag && !shdr->IsISlice() &&
!shdr->IsSISlice()) {
READ_UE_OR_RETURN(&shdr->cabac_init_idc);
TRUE_OR_RETURN(shdr->cabac_init_idc < 3);
}
READ_SE_OR_RETURN(&shdr->slice_qp_delta);
if (shdr->IsSPSlice() || shdr->IsSISlice()) {
if (shdr->IsSPSlice())
READ_BOOL_OR_RETURN(&shdr->sp_for_switch_flag);
READ_SE_OR_RETURN(&shdr->slice_qs_delta);
}
if (pps->deblocking_filter_control_present_flag) {
READ_UE_OR_RETURN(&shdr->disable_deblocking_filter_idc);
TRUE_OR_RETURN(shdr->disable_deblocking_filter_idc < 3);
if (shdr->disable_deblocking_filter_idc != 1) {
READ_SE_OR_RETURN(&shdr->slice_alpha_c0_offset_div2);
IN_RANGE_OR_RETURN(shdr->slice_alpha_c0_offset_div2, -6, 6);
READ_SE_OR_RETURN(&shdr->slice_beta_offset_div2);
IN_RANGE_OR_RETURN(shdr->slice_beta_offset_div2, -6, 6);
}
}
if (pps->num_slice_groups_minus1 > 0) {
DVLOG(1) << "Slice groups not supported";
return kUnsupportedStream;
}
size_t epb = br_.NumEmulationPreventionBytesRead();
shdr->header_bit_size = (shdr->nalu_size - epb) * 8 - br_.NumBitsLeft();
return kOk;
}
H264Parser::Result H264Parser::ParseSEI(H264SEI* sei) {
int byte;
int num_parsed_sei_msg = 0;
// According to spec 7.3.2.3, we should loop parsing SEI NALU
// as long as `more_rbsp_data` condition is true, which means
// if the NALU's RBSP data is large enough and `more_rbsp_data`
// condition keeps true all the time, we are very likely have to
// loop the parsing millions of times.
//
// The spec doesn't provide any pattern to let us validate the
// the parsed SEI messages, so we have to set a limit here.
constexpr int kMaxParsedSEIMessages = 64;
do {
H264SEIMessage sei_msg;
sei_msg.type = 0;
READ_BITS_OR_RETURN(8, &byte);
while (byte == 0xff) {
sei_msg.type += 255;
READ_BITS_OR_RETURN(8, &byte);
}
sei_msg.type += byte;
sei_msg.payload_size = 0;
READ_BITS_OR_RETURN(8, &byte);
while (byte == 0xff) {
sei_msg.payload_size += 255;
READ_BITS_OR_RETURN(8, &byte);
}
sei_msg.payload_size += byte;
int num_bits_remain = sei_msg.payload_size * 8;
DVLOG(4) << "Found SEI message type: " << sei_msg.type
<< " payload size: " << sei_msg.payload_size;
switch (sei_msg.type) {
case H264SEIMessage::kSEIRecoveryPoint:
READ_UE_AND_MINUS_BITS_READ_OR_RETURN(
&sei_msg.recovery_point.recovery_frame_cnt, &num_bits_remain);
READ_BOOL_AND_MINUS_BITS_READ_OR_RETURN(
&sei_msg.recovery_point.exact_match_flag, &num_bits_remain);
READ_BOOL_AND_MINUS_BITS_READ_OR_RETURN(
&sei_msg.recovery_point.broken_link_flag, &num_bits_remain);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(
2, &sei_msg.recovery_point.changing_slice_group_idc,
&num_bits_remain);
break;
case H264SEIMessage::kSEIContentLightLevelInfo:
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(
16, &sei_msg.content_light_level_info.max_content_light_level,
&num_bits_remain);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(
16,
&sei_msg.content_light_level_info.max_picture_average_light_level,
&num_bits_remain);
break;
case H264SEIMessage::kSEIMasteringDisplayInfo:
for (auto& primary : sei_msg.mastering_display_info.display_primaries) {
for (auto& component : primary) {
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(16, &component,
&num_bits_remain);
}
}
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(
16, &sei_msg.mastering_display_info.white_points[0],
&num_bits_remain);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(
16, &sei_msg.mastering_display_info.white_points[1],
&num_bits_remain);
uint32_t luminace_high_31bits, luminance_low_1bit;
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(31, &luminace_high_31bits,
&num_bits_remain);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(1, &luminance_low_1bit,
&num_bits_remain);
sei_msg.mastering_display_info.max_luminance =
(luminace_high_31bits << 1) + (luminance_low_1bit & 0x1);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(31, &luminace_high_31bits,
&num_bits_remain);
READ_BITS_AND_MINUS_BITS_READ_OR_RETURN(1, &luminance_low_1bit,
&num_bits_remain);
sei_msg.mastering_display_info.min_luminance =
(luminace_high_31bits << 1) + (luminance_low_1bit & 0x1);
break;
default:
DVLOG(4) << "Unsupported SEI message";
break;
}
TRUE_OR_RETURN(num_bits_remain >= 0);
// D.1.1 Not byted aligned in payload or unsupported SEI, skip bits.
if (num_bits_remain > 0)
SKIP_BITS_OR_RETURN(num_bits_remain);
// Only add parsed SEI messages.
if (num_bits_remain < sei_msg.payload_size * 8)
sei->msgs.push_back(sei_msg);
// In case the loop endless.
if (++num_parsed_sei_msg > kMaxParsedSEIMessages)
return kInvalidStream;
} while (br_.HasMoreRBSPData());
return kOk;
}
std::vector<SubsampleEntry> H264Parser::GetCurrentSubsamples() {
DCHECK_EQ(previous_nalu_range_.size(), 1u)
<< "This should only be called after a "
"successful call to AdvanceToNextNalu()";
auto intersection = encrypted_ranges_.IntersectionWith(previous_nalu_range_);
return EncryptedRangesToSubsampleEntry(
previous_nalu_range_.start(0), previous_nalu_range_.end(0), intersection);
}
} // namespace media