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webrtc/modules/rtp_rtcp/source/rtp_format_vp9.cc
Danil Chapovalov f7f8a1f176 Cleanup RtpPacketizer interface 
merge construction and call to SetPayloadData
Add NumPackets instead of SetPayloadData
Remove virtual ToString() as unused
move CHECK(rtp_video_header) from RtpPacketizer::Create to RtpSenderVideo::SendVideo

Bug: webrtc:9680
Change-Id: I074644e048c797eb836f79979df363fe1ea0075e
Reviewed-on: https://webrtc-review.googlesource.com/96543
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24474}
2018-08-29 08:44:08 +00:00

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/*
* 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 "modules/rtp_rtcp/source/rtp_format_vp9.h"
#include <assert.h>
#include <string.h>
#include <cmath>
#include "modules/rtp_rtcp/source/rtp_packet_to_send.h"
#include "rtc_base/bitbuffer.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#define RETURN_FALSE_ON_ERROR(x) \
if (!(x)) { \
return false; \
}
namespace webrtc {
namespace {
// Length of VP9 payload descriptors' fixed part.
const size_t kFixedPayloadDescriptorBytes = 1;
const uint32_t kReservedBitValue0 = 0;
uint8_t TemporalIdxField(const RTPVideoHeaderVP9& hdr, uint8_t def) {
return (hdr.temporal_idx == kNoTemporalIdx) ? def : hdr.temporal_idx;
}
uint8_t SpatialIdxField(const RTPVideoHeaderVP9& hdr, uint8_t def) {
return (hdr.spatial_idx == kNoSpatialIdx) ? def : hdr.spatial_idx;
}
int16_t Tl0PicIdxField(const RTPVideoHeaderVP9& hdr, uint8_t def) {
return (hdr.tl0_pic_idx == kNoTl0PicIdx) ? def : hdr.tl0_pic_idx;
}
// Picture ID:
//
// +-+-+-+-+-+-+-+-+
// I: |M| PICTURE ID | M:0 => picture id is 7 bits.
// +-+-+-+-+-+-+-+-+ M:1 => picture id is 15 bits.
// M: | EXTENDED PID |
// +-+-+-+-+-+-+-+-+
//
size_t PictureIdLength(const RTPVideoHeaderVP9& hdr) {
if (hdr.picture_id == kNoPictureId)
return 0;
return (hdr.max_picture_id == kMaxOneBytePictureId) ? 1 : 2;
}
bool PictureIdPresent(const RTPVideoHeaderVP9& hdr) {
return PictureIdLength(hdr) > 0;
}
// Layer indices:
//
// Flexible mode (F=1): Non-flexible mode (F=0):
//
// +-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
// L: | T |U| S |D| | T |U| S |D|
// +-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
// | TL0PICIDX |
// +-+-+-+-+-+-+-+-+
//
size_t LayerInfoLength(const RTPVideoHeaderVP9& hdr) {
if (hdr.temporal_idx == kNoTemporalIdx && hdr.spatial_idx == kNoSpatialIdx) {
return 0;
}
return hdr.flexible_mode ? 1 : 2;
}
bool LayerInfoPresent(const RTPVideoHeaderVP9& hdr) {
return LayerInfoLength(hdr) > 0;
}
// Reference indices:
//
// +-+-+-+-+-+-+-+-+ P=1,F=1: At least one reference index
// P,F: | P_DIFF |N| up to 3 times has to be specified.
// +-+-+-+-+-+-+-+-+ N=1: An additional P_DIFF follows
// current P_DIFF.
//
size_t RefIndicesLength(const RTPVideoHeaderVP9& hdr) {
if (!hdr.inter_pic_predicted || !hdr.flexible_mode)
return 0;
RTC_DCHECK_GT(hdr.num_ref_pics, 0U);
RTC_DCHECK_LE(hdr.num_ref_pics, kMaxVp9RefPics);
return hdr.num_ref_pics;
}
// Scalability structure (SS).
//
// +-+-+-+-+-+-+-+-+
// V: | N_S |Y|G|-|-|-|
// +-+-+-+-+-+-+-+-+ -|
// Y: | WIDTH | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ . N_S + 1 times
// | HEIGHT | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -|
// G: | N_G | (OPTIONAL)
// +-+-+-+-+-+-+-+-+ -|
// N_G: | T |U| R |-|-| (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -| . N_G times
// | P_DIFF | (OPTIONAL) . R times .
// +-+-+-+-+-+-+-+-+ -| -|
//
size_t SsDataLength(const RTPVideoHeaderVP9& hdr) {
if (!hdr.ss_data_available)
return 0;
RTC_DCHECK_GT(hdr.num_spatial_layers, 0U);
RTC_DCHECK_LE(hdr.num_spatial_layers, kMaxVp9NumberOfSpatialLayers);
RTC_DCHECK_LE(hdr.gof.num_frames_in_gof, kMaxVp9FramesInGof);
size_t length = 1; // V
if (hdr.spatial_layer_resolution_present) {
length += 4 * hdr.num_spatial_layers; // Y
}
if (hdr.gof.num_frames_in_gof > 0) {
++length; // G
}
// N_G
length += hdr.gof.num_frames_in_gof; // T, U, R
for (size_t i = 0; i < hdr.gof.num_frames_in_gof; ++i) {
RTC_DCHECK_LE(hdr.gof.num_ref_pics[i], kMaxVp9RefPics);
length += hdr.gof.num_ref_pics[i]; // R times
}
return length;
}
size_t PayloadDescriptorLengthMinusSsData(const RTPVideoHeaderVP9& hdr) {
return kFixedPayloadDescriptorBytes + PictureIdLength(hdr) +
LayerInfoLength(hdr) + RefIndicesLength(hdr);
}
size_t PayloadDescriptorLength(const RTPVideoHeaderVP9& hdr) {
return PayloadDescriptorLengthMinusSsData(hdr) + SsDataLength(hdr);
}
void QueuePacket(size_t start_pos,
size_t size,
bool layer_begin,
bool layer_end,
RtpPacketizerVp9::PacketInfoQueue* packets) {
RtpPacketizerVp9::PacketInfo packet_info;
packet_info.payload_start_pos = start_pos;
packet_info.size = size;
packet_info.layer_begin = layer_begin;
packet_info.layer_end = layer_end;
packets->push(packet_info);
}
// Picture ID:
//
// +-+-+-+-+-+-+-+-+
// I: |M| PICTURE ID | M:0 => picture id is 7 bits.
// +-+-+-+-+-+-+-+-+ M:1 => picture id is 15 bits.
// M: | EXTENDED PID |
// +-+-+-+-+-+-+-+-+
//
bool WritePictureId(const RTPVideoHeaderVP9& vp9,
rtc::BitBufferWriter* writer) {
bool m_bit = (PictureIdLength(vp9) == 2);
RETURN_FALSE_ON_ERROR(writer->WriteBits(m_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.picture_id, m_bit ? 15 : 7));
return true;
}
// Layer indices:
//
// Flexible mode (F=1):
//
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D|
// +-+-+-+-+-+-+-+-+
//
bool WriteLayerInfoCommon(const RTPVideoHeaderVP9& vp9,
rtc::BitBufferWriter* writer) {
RETURN_FALSE_ON_ERROR(writer->WriteBits(TemporalIdxField(vp9, 0), 3));
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.temporal_up_switch ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer->WriteBits(SpatialIdxField(vp9, 0), 3));
RETURN_FALSE_ON_ERROR(
writer->WriteBits(vp9.inter_layer_predicted ? 1 : 0, 1));
return true;
}
// Non-flexible mode (F=0):
//
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D|
// +-+-+-+-+-+-+-+-+
// | TL0PICIDX |
// +-+-+-+-+-+-+-+-+
//
bool WriteLayerInfoNonFlexibleMode(const RTPVideoHeaderVP9& vp9,
rtc::BitBufferWriter* writer) {
RETURN_FALSE_ON_ERROR(writer->WriteUInt8(Tl0PicIdxField(vp9, 0)));
return true;
}
bool WriteLayerInfo(const RTPVideoHeaderVP9& vp9,
rtc::BitBufferWriter* writer) {
if (!WriteLayerInfoCommon(vp9, writer))
return false;
if (vp9.flexible_mode)
return true;
return WriteLayerInfoNonFlexibleMode(vp9, writer);
}
// Reference indices:
//
// +-+-+-+-+-+-+-+-+ P=1,F=1: At least one reference index
// P,F: | P_DIFF |N| up to 3 times has to be specified.
// +-+-+-+-+-+-+-+-+ N=1: An additional P_DIFF follows
// current P_DIFF.
//
bool WriteRefIndices(const RTPVideoHeaderVP9& vp9,
rtc::BitBufferWriter* writer) {
if (!PictureIdPresent(vp9) || vp9.num_ref_pics == 0 ||
vp9.num_ref_pics > kMaxVp9RefPics) {
return false;
}
for (uint8_t i = 0; i < vp9.num_ref_pics; ++i) {
bool n_bit = !(i == vp9.num_ref_pics - 1);
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.pid_diff[i], 7));
RETURN_FALSE_ON_ERROR(writer->WriteBits(n_bit ? 1 : 0, 1));
}
return true;
}
// Scalability structure (SS).
//
// +-+-+-+-+-+-+-+-+
// V: | N_S |Y|G|-|-|-|
// +-+-+-+-+-+-+-+-+ -|
// Y: | WIDTH | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ . N_S + 1 times
// | HEIGHT | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -|
// G: | N_G | (OPTIONAL)
// +-+-+-+-+-+-+-+-+ -|
// N_G: | T |U| R |-|-| (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -| . N_G times
// | P_DIFF | (OPTIONAL) . R times .
// +-+-+-+-+-+-+-+-+ -| -|
//
bool WriteSsData(const RTPVideoHeaderVP9& vp9, rtc::BitBufferWriter* writer) {
RTC_DCHECK_GT(vp9.num_spatial_layers, 0U);
RTC_DCHECK_LE(vp9.num_spatial_layers, kMaxVp9NumberOfSpatialLayers);
RTC_DCHECK_LE(vp9.gof.num_frames_in_gof, kMaxVp9FramesInGof);
bool g_bit = vp9.gof.num_frames_in_gof > 0;
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.num_spatial_layers - 1, 3));
RETURN_FALSE_ON_ERROR(
writer->WriteBits(vp9.spatial_layer_resolution_present ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer->WriteBits(g_bit ? 1 : 0, 1)); // G
RETURN_FALSE_ON_ERROR(writer->WriteBits(kReservedBitValue0, 3));
if (vp9.spatial_layer_resolution_present) {
for (size_t i = 0; i < vp9.num_spatial_layers; ++i) {
RETURN_FALSE_ON_ERROR(writer->WriteUInt16(vp9.width[i]));
RETURN_FALSE_ON_ERROR(writer->WriteUInt16(vp9.height[i]));
}
}
if (g_bit) {
RETURN_FALSE_ON_ERROR(writer->WriteUInt8(vp9.gof.num_frames_in_gof));
}
for (size_t i = 0; i < vp9.gof.num_frames_in_gof; ++i) {
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.gof.temporal_idx[i], 3));
RETURN_FALSE_ON_ERROR(
writer->WriteBits(vp9.gof.temporal_up_switch[i] ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer->WriteBits(vp9.gof.num_ref_pics[i], 2));
RETURN_FALSE_ON_ERROR(writer->WriteBits(kReservedBitValue0, 2));
for (uint8_t r = 0; r < vp9.gof.num_ref_pics[i]; ++r) {
RETURN_FALSE_ON_ERROR(writer->WriteUInt8(vp9.gof.pid_diff[i][r]));
}
}
return true;
}
// Picture ID:
//
// +-+-+-+-+-+-+-+-+
// I: |M| PICTURE ID | M:0 => picture id is 7 bits.
// +-+-+-+-+-+-+-+-+ M:1 => picture id is 15 bits.
// M: | EXTENDED PID |
// +-+-+-+-+-+-+-+-+
//
bool ParsePictureId(rtc::BitBuffer* parser, RTPVideoHeaderVP9* vp9) {
uint32_t picture_id;
uint32_t m_bit;
RETURN_FALSE_ON_ERROR(parser->ReadBits(&m_bit, 1));
if (m_bit) {
RETURN_FALSE_ON_ERROR(parser->ReadBits(&picture_id, 15));
vp9->max_picture_id = kMaxTwoBytePictureId;
} else {
RETURN_FALSE_ON_ERROR(parser->ReadBits(&picture_id, 7));
vp9->max_picture_id = kMaxOneBytePictureId;
}
vp9->picture_id = picture_id;
return true;
}
// Layer indices (flexible mode):
//
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D|
// +-+-+-+-+-+-+-+-+
//
bool ParseLayerInfoCommon(rtc::BitBuffer* parser, RTPVideoHeaderVP9* vp9) {
uint32_t t, u_bit, s, d_bit;
RETURN_FALSE_ON_ERROR(parser->ReadBits(&t, 3));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&u_bit, 1));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&s, 3));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&d_bit, 1));
vp9->temporal_idx = t;
vp9->temporal_up_switch = u_bit ? true : false;
vp9->spatial_idx = s;
vp9->inter_layer_predicted = d_bit ? true : false;
return true;
}
// Layer indices (non-flexible mode):
//
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D|
// +-+-+-+-+-+-+-+-+
// | TL0PICIDX |
// +-+-+-+-+-+-+-+-+
//
bool ParseLayerInfoNonFlexibleMode(rtc::BitBuffer* parser,
RTPVideoHeaderVP9* vp9) {
uint8_t tl0picidx;
RETURN_FALSE_ON_ERROR(parser->ReadUInt8(&tl0picidx));
vp9->tl0_pic_idx = tl0picidx;
return true;
}
bool ParseLayerInfo(rtc::BitBuffer* parser, RTPVideoHeaderVP9* vp9) {
if (!ParseLayerInfoCommon(parser, vp9))
return false;
if (vp9->flexible_mode)
return true;
return ParseLayerInfoNonFlexibleMode(parser, vp9);
}
// Reference indices:
//
// +-+-+-+-+-+-+-+-+ P=1,F=1: At least one reference index
// P,F: | P_DIFF |N| up to 3 times has to be specified.
// +-+-+-+-+-+-+-+-+ N=1: An additional P_DIFF follows
// current P_DIFF.
//
bool ParseRefIndices(rtc::BitBuffer* parser, RTPVideoHeaderVP9* vp9) {
if (vp9->picture_id == kNoPictureId)
return false;
vp9->num_ref_pics = 0;
uint32_t n_bit;
do {
if (vp9->num_ref_pics == kMaxVp9RefPics)
return false;
uint32_t p_diff;
RETURN_FALSE_ON_ERROR(parser->ReadBits(&p_diff, 7));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&n_bit, 1));
vp9->pid_diff[vp9->num_ref_pics] = p_diff;
uint32_t scaled_pid = vp9->picture_id;
if (p_diff > scaled_pid) {
// TODO(asapersson): Max should correspond to the picture id of last wrap.
scaled_pid += vp9->max_picture_id + 1;
}
vp9->ref_picture_id[vp9->num_ref_pics++] = scaled_pid - p_diff;
} while (n_bit);
return true;
}
// Scalability structure (SS).
//
// +-+-+-+-+-+-+-+-+
// V: | N_S |Y|G|-|-|-|
// +-+-+-+-+-+-+-+-+ -|
// Y: | WIDTH | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ . N_S + 1 times
// | HEIGHT | (OPTIONAL) .
// + + .
// | | (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -|
// G: | N_G | (OPTIONAL)
// +-+-+-+-+-+-+-+-+ -|
// N_G: | T |U| R |-|-| (OPTIONAL) .
// +-+-+-+-+-+-+-+-+ -| . N_G times
// | P_DIFF | (OPTIONAL) . R times .
// +-+-+-+-+-+-+-+-+ -| -|
//
bool ParseSsData(rtc::BitBuffer* parser, RTPVideoHeaderVP9* vp9) {
uint32_t n_s, y_bit, g_bit;
RETURN_FALSE_ON_ERROR(parser->ReadBits(&n_s, 3));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&y_bit, 1));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&g_bit, 1));
RETURN_FALSE_ON_ERROR(parser->ConsumeBits(3));
vp9->num_spatial_layers = n_s + 1;
vp9->spatial_layer_resolution_present = y_bit ? true : false;
vp9->gof.num_frames_in_gof = 0;
if (y_bit) {
for (size_t i = 0; i < vp9->num_spatial_layers; ++i) {
RETURN_FALSE_ON_ERROR(parser->ReadUInt16(&vp9->width[i]));
RETURN_FALSE_ON_ERROR(parser->ReadUInt16(&vp9->height[i]));
}
}
if (g_bit) {
uint8_t n_g;
RETURN_FALSE_ON_ERROR(parser->ReadUInt8(&n_g));
vp9->gof.num_frames_in_gof = n_g;
}
for (size_t i = 0; i < vp9->gof.num_frames_in_gof; ++i) {
uint32_t t, u_bit, r;
RETURN_FALSE_ON_ERROR(parser->ReadBits(&t, 3));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&u_bit, 1));
RETURN_FALSE_ON_ERROR(parser->ReadBits(&r, 2));
RETURN_FALSE_ON_ERROR(parser->ConsumeBits(2));
vp9->gof.temporal_idx[i] = t;
vp9->gof.temporal_up_switch[i] = u_bit ? true : false;
vp9->gof.num_ref_pics[i] = r;
for (uint8_t p = 0; p < vp9->gof.num_ref_pics[i]; ++p) {
uint8_t p_diff;
RETURN_FALSE_ON_ERROR(parser->ReadUInt8(&p_diff));
vp9->gof.pid_diff[i][p] = p_diff;
}
}
return true;
}
} // namespace
RtpPacketizerVp9::RtpPacketizerVp9(const RTPVideoHeaderVP9& hdr,
size_t max_payload_length,
size_t last_packet_reduction_len)
: hdr_(hdr),
max_payload_length_(max_payload_length),
payload_(nullptr),
payload_size_(0),
last_packet_reduction_len_(last_packet_reduction_len) {}
RtpPacketizerVp9::~RtpPacketizerVp9() {}
size_t RtpPacketizerVp9::SetPayloadData(
const uint8_t* payload,
size_t payload_size,
const RTPFragmentationHeader* fragmentation) {
payload_ = payload;
payload_size_ = payload_size;
GeneratePackets();
return packets_.size();
}
size_t RtpPacketizerVp9::NumPackets() const {
return packets_.size();
}
// Splits payload in minimal number of roughly equal in size packets.
void RtpPacketizerVp9::GeneratePackets() {
if (max_payload_length_ < PayloadDescriptorLength(hdr_) + 1) {
RTC_LOG(LS_ERROR) << "Payload header and one payload byte won't fit in the "
"first packet.";
return;
}
if (max_payload_length_ < PayloadDescriptorLengthMinusSsData(hdr_) + 1 +
last_packet_reduction_len_) {
RTC_LOG(LS_ERROR)
<< "Payload header and one payload byte won't fit in the last"
" packet.";
return;
}
if (payload_size_ == 1 &&
max_payload_length_ <
PayloadDescriptorLength(hdr_) + 1 + last_packet_reduction_len_) {
RTC_LOG(LS_ERROR) << "Can't fit header and payload into single packet, but "
"payload size is one: no way to generate packets with "
"nonzero payload.";
return;
}
// Instead of making last packet smaller, we pretend that we must write
// additional data into it. We account for this virtual payload while
// calculating packets number and sizes. We also pretend that all packets
// headers are the same length and extra SS header data in the fits packet
// is also treated as a payload here.
size_t ss_data_len = SsDataLength(hdr_);
// Payload, virtual payload and SS hdr data in the first packet together.
size_t total_bytes = ss_data_len + payload_size_ + last_packet_reduction_len_;
// Now all packets will have the same lenght of vp9 headers.
size_t per_packet_capacity =
max_payload_length_ - PayloadDescriptorLengthMinusSsData(hdr_);
// Integer division rounding up.
size_t num_packets =
(total_bytes + per_packet_capacity - 1) / per_packet_capacity;
// Average rounded down.
size_t per_packet_bytes = total_bytes / num_packets;
// Several last packets are 1 byte larger than the rest.
// i.e. if 14 bytes were split between 4 packets, it would be 3+3+4+4.
size_t num_larger_packets = total_bytes % num_packets;
size_t bytes_processed = 0;
size_t num_packets_left = num_packets;
while (bytes_processed < payload_size_) {
if (num_packets_left == num_larger_packets)
++per_packet_bytes;
size_t packet_bytes = per_packet_bytes;
// First packet also has SS hdr data.
if (bytes_processed == 0) {
// Must write at least one byte of the real payload to the packet.
if (packet_bytes > ss_data_len) {
packet_bytes -= ss_data_len;
} else {
packet_bytes = 1;
}
}
size_t rem_bytes = payload_size_ - bytes_processed;
if (packet_bytes >= rem_bytes) {
// All remaining payload fits into this packet.
packet_bytes = rem_bytes;
// If this is the penultimate packet, leave at least 1 byte of payload for
// the last packet.
if (num_packets_left == 2)
--packet_bytes;
}
QueuePacket(bytes_processed, packet_bytes, bytes_processed == 0,
rem_bytes == packet_bytes, &packets_);
--num_packets_left;
bytes_processed += packet_bytes;
// Last packet should be smaller
RTC_DCHECK(num_packets_left > 0 ||
per_packet_capacity >=
packet_bytes + last_packet_reduction_len_);
}
RTC_CHECK_EQ(bytes_processed, payload_size_);
}
bool RtpPacketizerVp9::NextPacket(RtpPacketToSend* packet) {
RTC_DCHECK(packet);
if (packets_.empty()) {
return false;
}
PacketInfo packet_info = packets_.front();
packets_.pop();
if (!WriteHeaderAndPayload(packet_info, packet, packets_.empty())) {
return false;
}
// Ensure end_of_picture is always set on top spatial layer when it is not
// dropped.
RTC_DCHECK(hdr_.spatial_idx < hdr_.num_spatial_layers - 1 ||
hdr_.end_of_picture);
packet->SetMarker(packets_.empty() && hdr_.end_of_picture);
return true;
}
// VP9 format:
//
// Payload descriptor for F = 1 (flexible mode)
// 0 1 2 3 4 5 6 7
// +-+-+-+-+-+-+-+-+
// |I|P|L|F|B|E|V|Z| (REQUIRED)
// +-+-+-+-+-+-+-+-+
// I: |M| PICTURE ID | (RECOMMENDED)
// +-+-+-+-+-+-+-+-+
// M: | EXTENDED PID | (RECOMMENDED)
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D| (CONDITIONALLY RECOMMENDED)
// +-+-+-+-+-+-+-+-+ -|
// P,F: | P_DIFF |N| (CONDITIONALLY RECOMMENDED) . up to 3 times
// +-+-+-+-+-+-+-+-+ -|
// V: | SS |
// | .. |
// +-+-+-+-+-+-+-+-+
//
// Payload descriptor for F = 0 (non-flexible mode)
// 0 1 2 3 4 5 6 7
// +-+-+-+-+-+-+-+-+
// |I|P|L|F|B|E|V|Z| (REQUIRED)
// +-+-+-+-+-+-+-+-+
// I: |M| PICTURE ID | (RECOMMENDED)
// +-+-+-+-+-+-+-+-+
// M: | EXTENDED PID | (RECOMMENDED)
// +-+-+-+-+-+-+-+-+
// L: | T |U| S |D| (CONDITIONALLY RECOMMENDED)
// +-+-+-+-+-+-+-+-+
// | TL0PICIDX | (CONDITIONALLY REQUIRED)
// +-+-+-+-+-+-+-+-+
// V: | SS |
// | .. |
// +-+-+-+-+-+-+-+-+
bool RtpPacketizerVp9::WriteHeaderAndPayload(const PacketInfo& packet_info,
RtpPacketToSend* packet,
bool last) const {
uint8_t* buffer = packet->AllocatePayload(
last ? max_payload_length_ - last_packet_reduction_len_
: max_payload_length_);
RTC_DCHECK(buffer);
size_t header_length;
if (!WriteHeader(packet_info, buffer, &header_length))
return false;
// Copy payload data.
memcpy(&buffer[header_length], &payload_[packet_info.payload_start_pos],
packet_info.size);
packet->SetPayloadSize(header_length + packet_info.size);
return true;
}
bool RtpPacketizerVp9::WriteHeader(const PacketInfo& packet_info,
uint8_t* buffer,
size_t* header_length) const {
// Required payload descriptor byte.
bool i_bit = PictureIdPresent(hdr_);
bool p_bit = hdr_.inter_pic_predicted;
bool l_bit = LayerInfoPresent(hdr_);
bool f_bit = hdr_.flexible_mode;
bool b_bit = packet_info.layer_begin;
bool e_bit = packet_info.layer_end;
bool v_bit = hdr_.ss_data_available && b_bit;
bool z_bit = hdr_.non_ref_for_inter_layer_pred;
rtc::BitBufferWriter writer(buffer, max_payload_length_);
RETURN_FALSE_ON_ERROR(writer.WriteBits(i_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(p_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(l_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(f_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(b_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(e_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(v_bit ? 1 : 0, 1));
RETURN_FALSE_ON_ERROR(writer.WriteBits(z_bit ? 1 : 0, 1));
// Add fields that are present.
if (i_bit && !WritePictureId(hdr_, &writer)) {
RTC_LOG(LS_ERROR) << "Failed writing VP9 picture id.";
return false;
}
if (l_bit && !WriteLayerInfo(hdr_, &writer)) {
RTC_LOG(LS_ERROR) << "Failed writing VP9 layer info.";
return false;
}
if (p_bit && f_bit && !WriteRefIndices(hdr_, &writer)) {
RTC_LOG(LS_ERROR) << "Failed writing VP9 ref indices.";
return false;
}
if (v_bit && !WriteSsData(hdr_, &writer)) {
RTC_LOG(LS_ERROR) << "Failed writing VP9 SS data.";
return false;
}
size_t offset_bytes = 0;
size_t offset_bits = 0;
writer.GetCurrentOffset(&offset_bytes, &offset_bits);
assert(offset_bits == 0);
*header_length = offset_bytes;
return true;
}
bool RtpDepacketizerVp9::Parse(ParsedPayload* parsed_payload,
const uint8_t* payload,
size_t payload_length) {
assert(parsed_payload != nullptr);
if (payload_length == 0) {
RTC_LOG(LS_ERROR) << "Payload length is zero.";
return false;
}
// Parse mandatory first byte of payload descriptor.
rtc::BitBuffer parser(payload, payload_length);
uint32_t i_bit, p_bit, l_bit, f_bit, b_bit, e_bit, v_bit, z_bit;
RETURN_FALSE_ON_ERROR(parser.ReadBits(&i_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&p_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&l_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&f_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&b_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&e_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&v_bit, 1));
RETURN_FALSE_ON_ERROR(parser.ReadBits(&z_bit, 1));
// Parsed payload.
parsed_payload->video_header().width = 0;
parsed_payload->video_header().height = 0;
parsed_payload->video_header().simulcastIdx = 0;
parsed_payload->video_header().codec = kVideoCodecVP9;
parsed_payload->frame_type = p_bit ? kVideoFrameDelta : kVideoFrameKey;
auto& vp9_header = parsed_payload->video_header()
.video_type_header.emplace<RTPVideoHeaderVP9>();
vp9_header.InitRTPVideoHeaderVP9();
vp9_header.inter_pic_predicted = p_bit ? true : false;
vp9_header.flexible_mode = f_bit ? true : false;
vp9_header.beginning_of_frame = b_bit ? true : false;
vp9_header.end_of_frame = e_bit ? true : false;
vp9_header.ss_data_available = v_bit ? true : false;
vp9_header.non_ref_for_inter_layer_pred = z_bit ? true : false;
// Parse fields that are present.
if (i_bit && !ParsePictureId(&parser, &vp9_header)) {
RTC_LOG(LS_ERROR) << "Failed parsing VP9 picture id.";
return false;
}
if (l_bit && !ParseLayerInfo(&parser, &vp9_header)) {
RTC_LOG(LS_ERROR) << "Failed parsing VP9 layer info.";
return false;
}
if (p_bit && f_bit && !ParseRefIndices(&parser, &vp9_header)) {
RTC_LOG(LS_ERROR) << "Failed parsing VP9 ref indices.";
return false;
}
if (v_bit) {
if (!ParseSsData(&parser, &vp9_header)) {
RTC_LOG(LS_ERROR) << "Failed parsing VP9 SS data.";
return false;
}
if (vp9_header.spatial_layer_resolution_present) {
// TODO(asapersson): Add support for spatial layers.
parsed_payload->video_header().width = vp9_header.width[0];
parsed_payload->video_header().height = vp9_header.height[0];
}
}
parsed_payload->video_header().is_first_packet_in_frame =
b_bit && (!l_bit || !vp9_header.inter_layer_predicted);
uint64_t rem_bits = parser.RemainingBitCount();
assert(rem_bits % 8 == 0);
parsed_payload->payload_length = rem_bits / 8;
if (parsed_payload->payload_length == 0) {
RTC_LOG(LS_ERROR) << "Failed parsing VP9 payload data.";
return false;
}
parsed_payload->payload =
payload + payload_length - parsed_payload->payload_length;
return true;
}
} // namespace webrtc
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