Revert "Use ArrayView for byte stream parsing in VideoRtpDepacketizerH264"

This reverts commit 4b53e9af6126028497239b39321ec6740f8e2bc2.

Reason for revert: Bug: chromium:371054866

Original change's description:
> Use ArrayView for byte stream parsing in VideoRtpDepacketizerH264
>
>
> Bug: webrtc:42223344, webrtc:42225170
> Change-Id: Ia2025ab225499702c0abe47690742a9c0d6109b7
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/364380
> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
> Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
> Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#43147}

Bug: webrtc:42223344, webrtc:42225170, chromium:371054866
Change-Id: I5c0222add560622a6ce34622d80a4bf7f1fc3fae
No-Try: true
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/364560
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#43155}
This commit is contained in:
Danil Chapovalov 2024-10-03 08:46:19 +00:00 committed by WebRTC LUCI CQ
parent 89a552a5a3
commit 208491c8b9

View File

@ -24,7 +24,6 @@
#include "modules/rtp_rtcp/source/byte_io.h"
#include "modules/rtp_rtcp/source/rtp_format_h264.h"
#include "modules/rtp_rtcp/source/video_rtp_depacketizer.h"
#include "rtc_base/byte_buffer.h"
#include "rtc_base/checks.h"
#include "rtc_base/copy_on_write_buffer.h"
#include "rtc_base/logging.h"
@ -35,32 +34,34 @@ namespace {
constexpr size_t kNalHeaderSize = 1;
constexpr size_t kFuAHeaderSize = 2;
constexpr size_t kLengthFieldSize = 2;
constexpr size_t kStapAHeaderSize = kNalHeaderSize + kLengthFieldSize;
std::vector<rtc::ArrayView<const uint8_t>> ParseStapA(
rtc::ArrayView<const uint8_t> data) {
std::vector<rtc::ArrayView<const uint8_t>> nal_units;
rtc::ByteBufferReader reader(data);
if (!reader.Consume(kNalHeaderSize)) {
return nal_units;
}
// TODO(pbos): Avoid parsing this here as well as inside the jitter buffer.
bool ParseStapAStartOffsets(const uint8_t* nalu_ptr,
size_t length_remaining,
std::vector<size_t>* offsets) {
size_t offset = 0;
while (length_remaining > 0) {
// Buffer doesn't contain room for additional nalu length.
if (length_remaining < sizeof(uint16_t))
return false;
uint16_t nalu_size = ByteReader<uint16_t>::ReadBigEndian(nalu_ptr);
nalu_ptr += sizeof(uint16_t);
length_remaining -= sizeof(uint16_t);
if (nalu_size > length_remaining)
return false;
nalu_ptr += nalu_size;
length_remaining -= nalu_size;
while (reader.Length() > 0) {
uint16_t nalu_size;
if (!reader.ReadUInt16(&nalu_size)) {
return {};
}
if (nalu_size == 0 || nalu_size > reader.Length()) {
return {};
}
nal_units.emplace_back(reader.Data(), nalu_size);
reader.Consume(nalu_size);
offsets->push_back(offset + kStapAHeaderSize);
offset += kLengthFieldSize + nalu_size;
}
return nal_units;
return true;
}
std::optional<VideoRtpDepacketizer::ParsedRtpPayload> ProcessStapAOrSingleNalu(
rtc::CopyOnWriteBuffer rtp_payload) {
rtc::ArrayView<const uint8_t> payload_data(rtp_payload);
const uint8_t* const payload_data = rtp_payload.cdata();
std::optional<VideoRtpDepacketizer::ParsedRtpPayload> parsed_payload(
std::in_place);
bool modified_buffer = false;
@ -73,32 +74,50 @@ std::optional<VideoRtpDepacketizer::ParsedRtpPayload> ProcessStapAOrSingleNalu(
auto& h264_header = parsed_payload->video_header.video_type_header
.emplace<RTPVideoHeaderH264>();
const uint8_t* nalu_start = payload_data + kNalHeaderSize;
const size_t nalu_length = rtp_payload.size() - kNalHeaderSize;
uint8_t nal_type = payload_data[0] & kH264TypeMask;
std::vector<rtc::ArrayView<const uint8_t>> nal_units;
std::vector<size_t> nalu_start_offsets;
if (nal_type == H264::NaluType::kStapA) {
nal_units = ParseStapA(payload_data);
if (nal_units.empty()) {
RTC_LOG(LS_ERROR) << "Incorrect StapA packet.";
// Skip the StapA header (StapA NAL type + length).
if (rtp_payload.size() <= kStapAHeaderSize) {
RTC_LOG(LS_ERROR) << "StapA header truncated.";
return std::nullopt;
}
if (!ParseStapAStartOffsets(nalu_start, nalu_length, &nalu_start_offsets)) {
RTC_LOG(LS_ERROR) << "StapA packet with incorrect NALU packet lengths.";
return std::nullopt;
}
h264_header.packetization_type = kH264StapA;
h264_header.nalu_type = nal_units[0][0] & kH264TypeMask;
nal_type = payload_data[kStapAHeaderSize] & kH264TypeMask;
} else {
h264_header.packetization_type = kH264SingleNalu;
h264_header.nalu_type = nal_type;
nal_units.push_back(payload_data);
nalu_start_offsets.push_back(0);
}
h264_header.nalu_type = nal_type;
parsed_payload->video_header.frame_type = VideoFrameType::kVideoFrameDelta;
for (const rtc::ArrayView<const uint8_t>& nal_unit : nal_units) {
nalu_start_offsets.push_back(rtp_payload.size() +
kLengthFieldSize); // End offset.
for (size_t i = 0; i < nalu_start_offsets.size() - 1; ++i) {
size_t start_offset = nalu_start_offsets[i];
// End offset is actually start offset for next unit, excluding length field
// so remove that from this units length.
size_t end_offset = nalu_start_offsets[i + 1] - kLengthFieldSize;
if (end_offset - start_offset < H264::kNaluTypeSize) {
RTC_LOG(LS_ERROR) << "STAP-A packet too short";
return std::nullopt;
}
NaluInfo nalu;
nalu.type = nal_unit[0] & kH264TypeMask;
nalu.type = payload_data[start_offset] & kH264TypeMask;
nalu.sps_id = -1;
nalu.pps_id = -1;
rtc::ArrayView<const uint8_t> nalu_data =
nal_unit.subview(H264::kNaluTypeSize);
start_offset += H264::kNaluTypeSize;
rtc::ArrayView<const uint8_t> nalu_data(&payload_data[start_offset],
end_offset - start_offset);
switch (nalu.type) {
case H264::NaluType::kSps: {
// Check if VUI is present in SPS and if it needs to be modified to
@ -106,10 +125,8 @@ std::optional<VideoRtpDepacketizer::ParsedRtpPayload> ProcessStapAOrSingleNalu(
// Copy any previous data first (likely just the first header).
rtc::Buffer output_buffer;
size_t start_offset = nalu_data.data() - payload_data.data();
size_t end_offset = start_offset + nalu_data.size();
if (start_offset)
output_buffer.AppendData(payload_data.data(), start_offset);
output_buffer.AppendData(payload_data, start_offset);
std::optional<SpsParser::SpsState> sps;
@ -143,7 +160,8 @@ std::optional<VideoRtpDepacketizer::ParsedRtpPayload> ProcessStapAOrSingleNalu(
output_buffer.size());
// Append rest of packet.
parsed_payload->video_payload.AppendData(
payload_data.subview(end_offset));
&payload_data[end_offset],
nalu_length + kNalHeaderSize - end_offset);
modified_buffer = true;
[[fallthrough]];