Files
platform-external-webrtc/webrtc/modules/rtp_rtcp/source/rtp_sender.cc
isheriff 6b4b5f3770 Add sender controlled playout delay limits
This CL adds support for an extension on RTP frames to allow the sender
to specify the minimum and maximum playout delay limits.

The receiver makes a best-effort attempt to keep the capture-to-render delay
within this range. This allows different types of application to specify
different end-to-end delay goals. For example gaming can support rendering
of frames as soon as received on receiver to minimize delay. A movie playback
application can specify a minimum playout delay to allow fixed buffering
in presence of network jitter.

There are no tests at this time and most of testing is done with chromium
webrtc prototype.

On chromoting performance tests, this extension helps bring down end-to-end
delay by about 150 ms on small frames.

BUG=webrtc:5895

Review-Url: https://codereview.webrtc.org/2007743003
Cr-Commit-Position: refs/heads/master@{#13059}
2016-06-08 07:24:30 +00:00

2006 lines
67 KiB
C++

/*
* Copyright (c) 2012 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/rtp_sender.h"
#include <stdlib.h> // srand
#include <algorithm>
#include <utility>
#include "webrtc/base/checks.h"
#include "webrtc/base/logging.h"
#include "webrtc/base/trace_event.h"
#include "webrtc/base/timeutils.h"
#include "webrtc/call.h"
#include "webrtc/call/rtc_event_log.h"
#include "webrtc/modules/rtp_rtcp/include/rtp_cvo.h"
#include "webrtc/modules/rtp_rtcp/source/byte_io.h"
#include "webrtc/modules/rtp_rtcp/source/playout_delay_oracle.h"
#include "webrtc/modules/rtp_rtcp/source/rtp_sender_audio.h"
#include "webrtc/modules/rtp_rtcp/source/rtp_sender_video.h"
#include "webrtc/modules/rtp_rtcp/source/time_util.h"
namespace webrtc {
// Max in the RFC 3550 is 255 bytes, we limit it to be modulus 32 for SRTP.
static const size_t kMaxPaddingLength = 224;
static const int kSendSideDelayWindowMs = 1000;
static const uint32_t kAbsSendTimeFraction = 18;
namespace {
const size_t kRtpHeaderLength = 12;
const uint16_t kMaxInitRtpSeqNumber = 32767; // 2^15 -1.
const char* FrameTypeToString(FrameType frame_type) {
switch (frame_type) {
case kEmptyFrame:
return "empty";
case kAudioFrameSpeech: return "audio_speech";
case kAudioFrameCN: return "audio_cn";
case kVideoFrameKey: return "video_key";
case kVideoFrameDelta: return "video_delta";
}
return "";
}
// TODO(holmer): Merge this with the implementation in
// remote_bitrate_estimator_abs_send_time.cc.
uint32_t ConvertMsTo24Bits(int64_t time_ms) {
uint32_t time_24_bits =
static_cast<uint32_t>(
((static_cast<uint64_t>(time_ms) << kAbsSendTimeFraction) + 500) /
1000) &
0x00FFFFFF;
return time_24_bits;
}
} // namespace
RTPSender::BitrateAggregator::BitrateAggregator(
BitrateStatisticsObserver* bitrate_callback)
: callback_(bitrate_callback),
total_bitrate_observer_(*this),
retransmit_bitrate_observer_(*this),
ssrc_(0) {}
void RTPSender::BitrateAggregator::OnStatsUpdated() const {
if (callback_) {
callback_->Notify(total_bitrate_observer_.statistics(),
retransmit_bitrate_observer_.statistics(), ssrc_);
}
}
Bitrate::Observer* RTPSender::BitrateAggregator::total_bitrate_observer() {
return &total_bitrate_observer_;
}
Bitrate::Observer* RTPSender::BitrateAggregator::retransmit_bitrate_observer() {
return &retransmit_bitrate_observer_;
}
void RTPSender::BitrateAggregator::set_ssrc(uint32_t ssrc) {
ssrc_ = ssrc;
}
RTPSender::BitrateAggregator::BitrateObserver::BitrateObserver(
const BitrateAggregator& aggregator)
: aggregator_(aggregator) {}
// Implements Bitrate::Observer.
void RTPSender::BitrateAggregator::BitrateObserver::BitrateUpdated(
const BitrateStatistics& stats) {
statistics_ = stats;
aggregator_.OnStatsUpdated();
}
const BitrateStatistics&
RTPSender::BitrateAggregator::BitrateObserver::statistics() const {
return statistics_;
}
RTPSender::RTPSender(
bool audio,
Clock* clock,
Transport* transport,
RtpPacketSender* paced_sender,
TransportSequenceNumberAllocator* sequence_number_allocator,
TransportFeedbackObserver* transport_feedback_observer,
BitrateStatisticsObserver* bitrate_callback,
FrameCountObserver* frame_count_observer,
SendSideDelayObserver* send_side_delay_observer,
RtcEventLog* event_log,
SendPacketObserver* send_packet_observer)
: clock_(clock),
// TODO(holmer): Remove this conversion?
clock_delta_ms_(clock_->TimeInMilliseconds() - rtc::TimeMillis()),
random_(clock_->TimeInMicroseconds()),
bitrates_(bitrate_callback),
total_bitrate_sent_(clock, bitrates_.total_bitrate_observer()),
audio_configured_(audio),
audio_(audio ? new RTPSenderAudio(clock, this) : nullptr),
video_(audio ? nullptr : new RTPSenderVideo(clock, this)),
paced_sender_(paced_sender),
transport_sequence_number_allocator_(sequence_number_allocator),
transport_feedback_observer_(transport_feedback_observer),
last_capture_time_ms_sent_(0),
transport_(transport),
sending_media_(true), // Default to sending media.
max_payload_length_(IP_PACKET_SIZE - 28), // Default is IP-v4/UDP.
payload_type_(-1),
payload_type_map_(),
rtp_header_extension_map_(),
transmission_time_offset_(0),
absolute_send_time_(0),
rotation_(kVideoRotation_0),
video_rotation_active_(false),
transport_sequence_number_(0),
// NACK.
nack_byte_count_times_(),
nack_byte_count_(),
nack_bitrate_(clock, bitrates_.retransmit_bitrate_observer()),
playout_delay_active_(false),
packet_history_(clock),
// Statistics
rtp_stats_callback_(NULL),
frame_count_observer_(frame_count_observer),
send_side_delay_observer_(send_side_delay_observer),
event_log_(event_log),
send_packet_observer_(send_packet_observer),
// RTP variables
start_timestamp_forced_(false),
start_timestamp_(0),
ssrc_db_(SSRCDatabase::GetSSRCDatabase()),
remote_ssrc_(0),
sequence_number_forced_(false),
ssrc_forced_(false),
timestamp_(0),
capture_time_ms_(0),
last_timestamp_time_ms_(0),
media_has_been_sent_(false),
last_packet_marker_bit_(false),
csrcs_(),
rtx_(kRtxOff),
target_bitrate_(0) {
memset(nack_byte_count_times_, 0, sizeof(nack_byte_count_times_));
memset(nack_byte_count_, 0, sizeof(nack_byte_count_));
// We need to seed the random generator for BuildPaddingPacket() below.
// TODO(holmer,tommi): Note that TimeInMilliseconds might return 0 on Mac
// early on in the process.
srand(static_cast<uint32_t>(clock_->TimeInMilliseconds()));
ssrc_ = ssrc_db_->CreateSSRC();
RTC_DCHECK(ssrc_ != 0);
ssrc_rtx_ = ssrc_db_->CreateSSRC();
RTC_DCHECK(ssrc_rtx_ != 0);
bitrates_.set_ssrc(ssrc_);
// Random start, 16 bits. Can't be 0.
sequence_number_rtx_ = random_.Rand(1, kMaxInitRtpSeqNumber);
sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber);
}
RTPSender::~RTPSender() {
// TODO(tommi): Use a thread checker to ensure the object is created and
// deleted on the same thread. At the moment this isn't possible due to
// voe::ChannelOwner in voice engine. To reproduce, run:
// voe_auto_test --automated --gtest_filter=*MixManyChannelsForStressOpus
// TODO(tommi,holmer): We don't grab locks in the dtor before accessing member
// variables but we grab them in all other methods. (what's the design?)
// Start documenting what thread we're on in what method so that it's easier
// to understand performance attributes and possibly remove locks.
if (remote_ssrc_ != 0) {
ssrc_db_->ReturnSSRC(remote_ssrc_);
}
ssrc_db_->ReturnSSRC(ssrc_);
SSRCDatabase::ReturnSSRCDatabase();
while (!payload_type_map_.empty()) {
std::map<int8_t, RtpUtility::Payload*>::iterator it =
payload_type_map_.begin();
delete it->second;
payload_type_map_.erase(it);
}
}
void RTPSender::SetTargetBitrate(uint32_t bitrate) {
rtc::CritScope cs(&target_bitrate_critsect_);
target_bitrate_ = bitrate;
}
uint32_t RTPSender::GetTargetBitrate() {
rtc::CritScope cs(&target_bitrate_critsect_);
return target_bitrate_;
}
uint16_t RTPSender::ActualSendBitrateKbit() const {
return (uint16_t)(total_bitrate_sent_.BitrateNow() / 1000);
}
uint32_t RTPSender::VideoBitrateSent() const {
if (video_) {
return video_->VideoBitrateSent();
}
return 0;
}
uint32_t RTPSender::FecOverheadRate() const {
if (video_) {
return video_->FecOverheadRate();
}
return 0;
}
uint32_t RTPSender::NackOverheadRate() const {
return nack_bitrate_.BitrateLast();
}
int32_t RTPSender::SetTransmissionTimeOffset(int32_t transmission_time_offset) {
if (transmission_time_offset > (0x800000 - 1) ||
transmission_time_offset < -(0x800000 - 1)) { // Word24.
return -1;
}
rtc::CritScope lock(&send_critsect_);
transmission_time_offset_ = transmission_time_offset;
return 0;
}
int32_t RTPSender::SetAbsoluteSendTime(uint32_t absolute_send_time) {
if (absolute_send_time > 0xffffff) { // UWord24.
return -1;
}
rtc::CritScope lock(&send_critsect_);
absolute_send_time_ = absolute_send_time;
return 0;
}
void RTPSender::SetVideoRotation(VideoRotation rotation) {
rtc::CritScope lock(&send_critsect_);
rotation_ = rotation;
}
int32_t RTPSender::SetTransportSequenceNumber(uint16_t sequence_number) {
rtc::CritScope lock(&send_critsect_);
transport_sequence_number_ = sequence_number;
return 0;
}
int32_t RTPSender::RegisterRtpHeaderExtension(RTPExtensionType type,
uint8_t id) {
rtc::CritScope lock(&send_critsect_);
switch (type) {
case kRtpExtensionVideoRotation:
video_rotation_active_ = false;
return rtp_header_extension_map_.RegisterInactive(type, id);
case kRtpExtensionPlayoutDelay:
playout_delay_active_ = false;
return rtp_header_extension_map_.RegisterInactive(type, id);
case kRtpExtensionTransmissionTimeOffset:
case kRtpExtensionAbsoluteSendTime:
case kRtpExtensionAudioLevel:
case kRtpExtensionTransportSequenceNumber:
return rtp_header_extension_map_.Register(type, id);
case kRtpExtensionNone:
LOG(LS_ERROR) << "Invalid RTP extension type for registration";
return -1;
}
return -1;
}
bool RTPSender::IsRtpHeaderExtensionRegistered(RTPExtensionType type) {
rtc::CritScope lock(&send_critsect_);
return rtp_header_extension_map_.IsRegistered(type);
}
int32_t RTPSender::DeregisterRtpHeaderExtension(RTPExtensionType type) {
rtc::CritScope lock(&send_critsect_);
return rtp_header_extension_map_.Deregister(type);
}
size_t RTPSender::RtpHeaderExtensionLength() const {
rtc::CritScope lock(&send_critsect_);
return rtp_header_extension_map_.GetTotalLengthInBytes();
}
int32_t RTPSender::RegisterPayload(
const char payload_name[RTP_PAYLOAD_NAME_SIZE],
int8_t payload_number,
uint32_t frequency,
size_t channels,
uint32_t rate) {
RTC_DCHECK_LT(strlen(payload_name), RTP_PAYLOAD_NAME_SIZE);
rtc::CritScope lock(&send_critsect_);
std::map<int8_t, RtpUtility::Payload*>::iterator it =
payload_type_map_.find(payload_number);
if (payload_type_map_.end() != it) {
// We already use this payload type.
RtpUtility::Payload* payload = it->second;
assert(payload);
// Check if it's the same as we already have.
if (RtpUtility::StringCompare(
payload->name, payload_name, RTP_PAYLOAD_NAME_SIZE - 1)) {
if (audio_configured_ && payload->audio &&
payload->typeSpecific.Audio.frequency == frequency &&
(payload->typeSpecific.Audio.rate == rate ||
payload->typeSpecific.Audio.rate == 0 || rate == 0)) {
payload->typeSpecific.Audio.rate = rate;
// Ensure that we update the rate if new or old is zero.
return 0;
}
if (!audio_configured_ && !payload->audio) {
return 0;
}
}
return -1;
}
int32_t ret_val = 0;
RtpUtility::Payload* payload = nullptr;
if (audio_configured_) {
// TODO(mflodman): Change to CreateAudioPayload and make static.
ret_val = audio_->RegisterAudioPayload(payload_name, payload_number,
frequency, channels, rate, &payload);
} else {
payload = video_->CreateVideoPayload(payload_name, payload_number);
}
if (payload) {
payload_type_map_[payload_number] = payload;
}
return ret_val;
}
int32_t RTPSender::DeRegisterSendPayload(int8_t payload_type) {
rtc::CritScope lock(&send_critsect_);
std::map<int8_t, RtpUtility::Payload*>::iterator it =
payload_type_map_.find(payload_type);
if (payload_type_map_.end() == it) {
return -1;
}
RtpUtility::Payload* payload = it->second;
delete payload;
payload_type_map_.erase(it);
return 0;
}
void RTPSender::SetSendPayloadType(int8_t payload_type) {
rtc::CritScope lock(&send_critsect_);
payload_type_ = payload_type;
}
int8_t RTPSender::SendPayloadType() const {
rtc::CritScope lock(&send_critsect_);
return payload_type_;
}
int RTPSender::SendPayloadFrequency() const {
return audio_ != NULL ? audio_->AudioFrequency() : kVideoPayloadTypeFrequency;
}
void RTPSender::SetMaxPayloadLength(size_t max_payload_length) {
// Sanity check.
RTC_DCHECK(max_payload_length >= 100 && max_payload_length <= IP_PACKET_SIZE)
<< "Invalid max payload length: " << max_payload_length;
rtc::CritScope lock(&send_critsect_);
max_payload_length_ = max_payload_length;
}
size_t RTPSender::MaxDataPayloadLength() const {
int rtx;
{
rtc::CritScope lock(&send_critsect_);
rtx = rtx_;
}
if (audio_configured_) {
return max_payload_length_ - RtpHeaderLength();
} else {
return max_payload_length_ - RtpHeaderLength() // RTP overhead.
- video_->FECPacketOverhead() // FEC/ULP/RED overhead.
- ((rtx) ? 2 : 0); // RTX overhead.
}
}
size_t RTPSender::MaxPayloadLength() const {
return max_payload_length_;
}
void RTPSender::SetRtxStatus(int mode) {
rtc::CritScope lock(&send_critsect_);
rtx_ = mode;
}
int RTPSender::RtxStatus() const {
rtc::CritScope lock(&send_critsect_);
return rtx_;
}
void RTPSender::SetRtxSsrc(uint32_t ssrc) {
rtc::CritScope lock(&send_critsect_);
ssrc_rtx_ = ssrc;
}
uint32_t RTPSender::RtxSsrc() const {
rtc::CritScope lock(&send_critsect_);
return ssrc_rtx_;
}
void RTPSender::SetRtxPayloadType(int payload_type,
int associated_payload_type) {
rtc::CritScope lock(&send_critsect_);
RTC_DCHECK_LE(payload_type, 127);
RTC_DCHECK_LE(associated_payload_type, 127);
if (payload_type < 0) {
LOG(LS_ERROR) << "Invalid RTX payload type: " << payload_type;
return;
}
rtx_payload_type_map_[associated_payload_type] = payload_type;
}
int32_t RTPSender::CheckPayloadType(int8_t payload_type,
RtpVideoCodecTypes* video_type) {
rtc::CritScope lock(&send_critsect_);
if (payload_type < 0) {
LOG(LS_ERROR) << "Invalid payload_type " << payload_type;
return -1;
}
if (audio_configured_) {
int8_t red_pl_type = -1;
if (audio_->RED(&red_pl_type) == 0) {
// We have configured RED.
if (red_pl_type == payload_type) {
// And it's a match...
return 0;
}
}
}
if (payload_type_ == payload_type) {
if (!audio_configured_) {
*video_type = video_->VideoCodecType();
}
return 0;
}
std::map<int8_t, RtpUtility::Payload*>::iterator it =
payload_type_map_.find(payload_type);
if (it == payload_type_map_.end()) {
LOG(LS_WARNING) << "Payload type " << static_cast<int>(payload_type)
<< " not registered.";
return -1;
}
SetSendPayloadType(payload_type);
RtpUtility::Payload* payload = it->second;
assert(payload);
if (!payload->audio && !audio_configured_) {
video_->SetVideoCodecType(payload->typeSpecific.Video.videoCodecType);
*video_type = payload->typeSpecific.Video.videoCodecType;
}
return 0;
}
bool RTPSender::ActivateCVORtpHeaderExtension() {
if (!video_rotation_active_) {
rtc::CritScope lock(&send_critsect_);
if (rtp_header_extension_map_.SetActive(kRtpExtensionVideoRotation, true)) {
video_rotation_active_ = true;
}
}
return video_rotation_active_;
}
int32_t RTPSender::SendOutgoingData(FrameType frame_type,
int8_t payload_type,
uint32_t capture_timestamp,
int64_t capture_time_ms,
const uint8_t* payload_data,
size_t payload_size,
const RTPFragmentationHeader* fragmentation,
const RTPVideoHeader* rtp_hdr) {
uint32_t ssrc;
uint16_t sequence_number;
{
// Drop this packet if we're not sending media packets.
rtc::CritScope lock(&send_critsect_);
ssrc = ssrc_;
sequence_number = sequence_number_;
if (!sending_media_) {
return 0;
}
}
RtpVideoCodecTypes video_type = kRtpVideoGeneric;
if (CheckPayloadType(payload_type, &video_type) != 0) {
LOG(LS_ERROR) << "Don't send data with unknown payload type: "
<< static_cast<int>(payload_type) << ".";
return -1;
}
int32_t ret_val;
if (audio_configured_) {
TRACE_EVENT_ASYNC_STEP1("webrtc", "Audio", capture_timestamp,
"Send", "type", FrameTypeToString(frame_type));
assert(frame_type == kAudioFrameSpeech || frame_type == kAudioFrameCN ||
frame_type == kEmptyFrame);
ret_val = audio_->SendAudio(frame_type, payload_type, capture_timestamp,
payload_data, payload_size, fragmentation);
} else {
TRACE_EVENT_ASYNC_STEP1("webrtc", "Video", capture_time_ms,
"Send", "type", FrameTypeToString(frame_type));
assert(frame_type != kAudioFrameSpeech && frame_type != kAudioFrameCN);
if (frame_type == kEmptyFrame)
return 0;
if (rtp_hdr) {
playout_delay_oracle_.UpdateRequest(ssrc, rtp_hdr->playout_delay,
sequence_number);
}
// Update the active/inactive status of playout delay extension based
// on what the oracle indicates.
{
rtc::CritScope lock(&send_critsect_);
if (playout_delay_active_ != playout_delay_oracle_.send_playout_delay()) {
playout_delay_active_ = playout_delay_oracle_.send_playout_delay();
rtp_header_extension_map_.SetActive(kRtpExtensionPlayoutDelay,
playout_delay_active_);
}
}
ret_val = video_->SendVideo(
video_type, frame_type, payload_type, capture_timestamp,
capture_time_ms, payload_data, payload_size, fragmentation, rtp_hdr);
}
rtc::CritScope cs(&statistics_crit_);
// Note: This is currently only counting for video.
if (frame_type == kVideoFrameKey) {
++frame_counts_.key_frames;
} else if (frame_type == kVideoFrameDelta) {
++frame_counts_.delta_frames;
}
if (frame_count_observer_) {
frame_count_observer_->FrameCountUpdated(frame_counts_, ssrc);
}
return ret_val;
}
size_t RTPSender::TrySendRedundantPayloads(size_t bytes_to_send,
int probe_cluster_id) {
{
rtc::CritScope lock(&send_critsect_);
if (!sending_media_)
return 0;
if ((rtx_ & kRtxRedundantPayloads) == 0)
return 0;
}
uint8_t buffer[IP_PACKET_SIZE];
int bytes_left = static_cast<int>(bytes_to_send);
while (bytes_left > 0) {
size_t length = bytes_left;
int64_t capture_time_ms;
if (!packet_history_.GetBestFittingPacket(buffer, &length,
&capture_time_ms)) {
break;
}
if (!PrepareAndSendPacket(buffer, length, capture_time_ms, true, false,
probe_cluster_id))
break;
RtpUtility::RtpHeaderParser rtp_parser(buffer, length);
RTPHeader rtp_header;
rtp_parser.Parse(&rtp_header);
bytes_left -= static_cast<int>(length - rtp_header.headerLength);
}
return bytes_to_send - bytes_left;
}
void RTPSender::BuildPaddingPacket(uint8_t* packet,
size_t header_length,
size_t padding_length) {
packet[0] |= 0x20; // Set padding bit.
int32_t* data = reinterpret_cast<int32_t*>(&(packet[header_length]));
// Fill data buffer with random data.
for (size_t j = 0; j < (padding_length >> 2); ++j) {
data[j] = rand(); // NOLINT
}
// Set number of padding bytes in the last byte of the packet.
packet[header_length + padding_length - 1] =
static_cast<uint8_t>(padding_length);
}
size_t RTPSender::SendPadData(size_t bytes,
bool timestamp_provided,
uint32_t timestamp,
int64_t capture_time_ms) {
return SendPadData(bytes, timestamp_provided, timestamp, capture_time_ms,
PacketInfo::kNotAProbe);
}
size_t RTPSender::SendPadData(size_t bytes,
bool timestamp_provided,
uint32_t timestamp,
int64_t capture_time_ms,
int probe_cluster_id) {
// Always send full padding packets. This is accounted for by the
// RtpPacketSender,
// which will make sure we don't send too much padding even if a single packet
// is larger than requested.
size_t padding_bytes_in_packet =
std::min(MaxDataPayloadLength(), kMaxPaddingLength);
size_t bytes_sent = 0;
bool using_transport_seq = rtp_header_extension_map_.IsRegistered(
kRtpExtensionTransportSequenceNumber) &&
transport_sequence_number_allocator_;
for (; bytes > 0; bytes -= padding_bytes_in_packet) {
if (bytes < padding_bytes_in_packet)
bytes = padding_bytes_in_packet;
uint32_t ssrc;
uint16_t sequence_number;
int payload_type;
bool over_rtx;
{
rtc::CritScope lock(&send_critsect_);
if (!sending_media_)
return bytes_sent;
if (!timestamp_provided) {
timestamp = timestamp_;
capture_time_ms = capture_time_ms_;
}
if (rtx_ == kRtxOff) {
// Without RTX we can't send padding in the middle of frames.
if (!last_packet_marker_bit_)
return 0;
ssrc = ssrc_;
sequence_number = sequence_number_;
++sequence_number_;
payload_type = payload_type_;
over_rtx = false;
} else {
// Without abs-send-time or transport sequence number a media packet
// must be sent before padding so that the timestamps used for
// estimation are correct.
if (!media_has_been_sent_ &&
!(rtp_header_extension_map_.IsRegistered(
kRtpExtensionAbsoluteSendTime) ||
using_transport_seq)) {
return 0;
}
// Only change change the timestamp of padding packets sent over RTX.
// Padding only packets over RTP has to be sent as part of a media
// frame (and therefore the same timestamp).
if (last_timestamp_time_ms_ > 0) {
timestamp +=
(clock_->TimeInMilliseconds() - last_timestamp_time_ms_) * 90;
capture_time_ms +=
(clock_->TimeInMilliseconds() - last_timestamp_time_ms_);
}
ssrc = ssrc_rtx_;
sequence_number = sequence_number_rtx_;
++sequence_number_rtx_;
payload_type = rtx_payload_type_map_.begin()->second;
over_rtx = true;
}
}
uint8_t padding_packet[IP_PACKET_SIZE];
size_t header_length =
CreateRtpHeader(padding_packet, payload_type, ssrc, false, timestamp,
sequence_number, std::vector<uint32_t>());
BuildPaddingPacket(padding_packet, header_length, padding_bytes_in_packet);
size_t length = padding_bytes_in_packet + header_length;
int64_t now_ms = clock_->TimeInMilliseconds();
RtpUtility::RtpHeaderParser rtp_parser(padding_packet, length);
RTPHeader rtp_header;
rtp_parser.Parse(&rtp_header);
if (capture_time_ms > 0) {
UpdateTransmissionTimeOffset(
padding_packet, length, rtp_header, now_ms - capture_time_ms);
}
UpdateAbsoluteSendTime(padding_packet, length, rtp_header, now_ms);
PacketOptions options;
if (AllocateTransportSequenceNumber(&options.packet_id)) {
if (UpdateTransportSequenceNumber(options.packet_id, padding_packet,
length, rtp_header)) {
if (transport_feedback_observer_)
transport_feedback_observer_->AddPacket(options.packet_id, length,
true, probe_cluster_id);
}
}
if (!SendPacketToNetwork(padding_packet, length, options))
break;
bytes_sent += padding_bytes_in_packet;
UpdateRtpStats(padding_packet, length, rtp_header, over_rtx, false);
}
return bytes_sent;
}
void RTPSender::SetStorePacketsStatus(bool enable, uint16_t number_to_store) {
packet_history_.SetStorePacketsStatus(enable, number_to_store);
}
bool RTPSender::StorePackets() const {
return packet_history_.StorePackets();
}
int32_t RTPSender::ReSendPacket(uint16_t packet_id, int64_t min_resend_time) {
size_t length = IP_PACKET_SIZE;
uint8_t data_buffer[IP_PACKET_SIZE];
int64_t capture_time_ms;
if (!packet_history_.GetPacketAndSetSendTime(packet_id, min_resend_time, true,
data_buffer, &length,
&capture_time_ms)) {
// Packet not found.
return 0;
}
if (paced_sender_) {
RtpUtility::RtpHeaderParser rtp_parser(data_buffer, length);
RTPHeader header;
if (!rtp_parser.Parse(&header)) {
assert(false);
return -1;
}
// Convert from TickTime to Clock since capture_time_ms is based on
// TickTime.
int64_t corrected_capture_tims_ms = capture_time_ms + clock_delta_ms_;
paced_sender_->InsertPacket(
RtpPacketSender::kNormalPriority, header.ssrc, header.sequenceNumber,
corrected_capture_tims_ms, length - header.headerLength, true);
return length;
}
int rtx = kRtxOff;
{
rtc::CritScope lock(&send_critsect_);
rtx = rtx_;
}
if (!PrepareAndSendPacket(data_buffer, length, capture_time_ms,
(rtx & kRtxRetransmitted) > 0, true,
PacketInfo::kNotAProbe)) {
return -1;
}
return static_cast<int32_t>(length);
}
bool RTPSender::SendPacketToNetwork(const uint8_t* packet,
size_t size,
const PacketOptions& options) {
int bytes_sent = -1;
if (transport_) {
bytes_sent = transport_->SendRtp(packet, size, options)
? static_cast<int>(size)
: -1;
if (event_log_ && bytes_sent > 0) {
event_log_->LogRtpHeader(kOutgoingPacket, MediaType::ANY, packet, size);
}
}
TRACE_EVENT_INSTANT2(TRACE_DISABLED_BY_DEFAULT("webrtc_rtp"),
"RTPSender::SendPacketToNetwork", "size", size, "sent",
bytes_sent);
// TODO(pwestin): Add a separate bitrate for sent bitrate after pacer.
if (bytes_sent <= 0) {
LOG(LS_WARNING) << "Transport failed to send packet";
return false;
}
return true;
}
int RTPSender::SelectiveRetransmissions() const {
if (!video_)
return -1;
return video_->SelectiveRetransmissions();
}
int RTPSender::SetSelectiveRetransmissions(uint8_t settings) {
if (!video_)
return -1;
video_->SetSelectiveRetransmissions(settings);
return 0;
}
void RTPSender::OnReceivedNACK(const std::list<uint16_t>& nack_sequence_numbers,
int64_t avg_rtt) {
TRACE_EVENT2(TRACE_DISABLED_BY_DEFAULT("webrtc_rtp"),
"RTPSender::OnReceivedNACK", "num_seqnum",
nack_sequence_numbers.size(), "avg_rtt", avg_rtt);
const int64_t now = clock_->TimeInMilliseconds();
uint32_t bytes_re_sent = 0;
uint32_t target_bitrate = GetTargetBitrate();
// Enough bandwidth to send NACK?
if (!ProcessNACKBitRate(now)) {
LOG(LS_INFO) << "NACK bitrate reached. Skip sending NACK response. Target "
<< target_bitrate;
return;
}
for (std::list<uint16_t>::const_iterator it = nack_sequence_numbers.begin();
it != nack_sequence_numbers.end(); ++it) {
const int32_t bytes_sent = ReSendPacket(*it, 5 + avg_rtt);
if (bytes_sent > 0) {
bytes_re_sent += bytes_sent;
} else if (bytes_sent == 0) {
// The packet has previously been resent.
// Try resending next packet in the list.
continue;
} else {
// Failed to send one Sequence number. Give up the rest in this nack.
LOG(LS_WARNING) << "Failed resending RTP packet " << *it
<< ", Discard rest of packets";
break;
}
// Delay bandwidth estimate (RTT * BW).
if (target_bitrate != 0 && avg_rtt) {
// kbits/s * ms = bits => bits/8 = bytes
size_t target_bytes =
(static_cast<size_t>(target_bitrate / 1000) * avg_rtt) >> 3;
if (bytes_re_sent > target_bytes) {
break; // Ignore the rest of the packets in the list.
}
}
}
if (bytes_re_sent > 0) {
UpdateNACKBitRate(bytes_re_sent, now);
}
}
void RTPSender::OnReceivedRtcpReportBlocks(
const ReportBlockList& report_blocks) {
playout_delay_oracle_.OnReceivedRtcpReportBlocks(report_blocks);
}
bool RTPSender::ProcessNACKBitRate(uint32_t now) {
uint32_t num = 0;
size_t byte_count = 0;
const uint32_t kAvgIntervalMs = 1000;
uint32_t target_bitrate = GetTargetBitrate();
rtc::CritScope lock(&send_critsect_);
if (target_bitrate == 0) {
return true;
}
for (num = 0; num < NACK_BYTECOUNT_SIZE; ++num) {
if ((now - nack_byte_count_times_[num]) > kAvgIntervalMs) {
// Don't use data older than 1sec.
break;
} else {
byte_count += nack_byte_count_[num];
}
}
uint32_t time_interval = kAvgIntervalMs;
if (num == NACK_BYTECOUNT_SIZE) {
// More than NACK_BYTECOUNT_SIZE nack messages has been received
// during the last msg_interval.
if (nack_byte_count_times_[num - 1] <= now) {
time_interval = now - nack_byte_count_times_[num - 1];
}
}
return (byte_count * 8) < (target_bitrate / 1000 * time_interval);
}
void RTPSender::UpdateNACKBitRate(uint32_t bytes, int64_t now) {
rtc::CritScope lock(&send_critsect_);
if (bytes == 0)
return;
nack_bitrate_.Update(bytes);
// Save bitrate statistics.
// Shift all but first time.
for (int i = NACK_BYTECOUNT_SIZE - 2; i >= 0; i--) {
nack_byte_count_[i + 1] = nack_byte_count_[i];
nack_byte_count_times_[i + 1] = nack_byte_count_times_[i];
}
nack_byte_count_[0] = bytes;
nack_byte_count_times_[0] = now;
}
// Called from pacer when we can send the packet.
bool RTPSender::TimeToSendPacket(uint16_t sequence_number,
int64_t capture_time_ms,
bool retransmission,
int probe_cluster_id) {
size_t length = IP_PACKET_SIZE;
uint8_t data_buffer[IP_PACKET_SIZE];
int64_t stored_time_ms;
if (!packet_history_.GetPacketAndSetSendTime(sequence_number,
0,
retransmission,
data_buffer,
&length,
&stored_time_ms)) {
// Packet cannot be found. Allow sending to continue.
return true;
}
int rtx;
{
rtc::CritScope lock(&send_critsect_);
rtx = rtx_;
}
return PrepareAndSendPacket(data_buffer, length, capture_time_ms,
retransmission && (rtx & kRtxRetransmitted) > 0,
retransmission, probe_cluster_id);
}
bool RTPSender::PrepareAndSendPacket(uint8_t* buffer,
size_t length,
int64_t capture_time_ms,
bool send_over_rtx,
bool is_retransmit,
int probe_cluster_id) {
uint8_t* buffer_to_send_ptr = buffer;
RtpUtility::RtpHeaderParser rtp_parser(buffer, length);
RTPHeader rtp_header;
rtp_parser.Parse(&rtp_header);
if (!is_retransmit && rtp_header.markerBit) {
TRACE_EVENT_ASYNC_END0(TRACE_DISABLED_BY_DEFAULT("webrtc_rtp"), "PacedSend",
capture_time_ms);
}
TRACE_EVENT_INSTANT2(
TRACE_DISABLED_BY_DEFAULT("webrtc_rtp"), "PrepareAndSendPacket",
"timestamp", rtp_header.timestamp, "seqnum", rtp_header.sequenceNumber);
uint8_t data_buffer_rtx[IP_PACKET_SIZE];
if (send_over_rtx) {
BuildRtxPacket(buffer, &length, data_buffer_rtx);
buffer_to_send_ptr = data_buffer_rtx;
}
int64_t now_ms = clock_->TimeInMilliseconds();
int64_t diff_ms = now_ms - capture_time_ms;
UpdateTransmissionTimeOffset(buffer_to_send_ptr, length, rtp_header,
diff_ms);
UpdateAbsoluteSendTime(buffer_to_send_ptr, length, rtp_header, now_ms);
PacketOptions options;
if (AllocateTransportSequenceNumber(&options.packet_id)) {
if (UpdateTransportSequenceNumber(options.packet_id, buffer_to_send_ptr,
length, rtp_header)) {
if (transport_feedback_observer_)
transport_feedback_observer_->AddPacket(options.packet_id, length, true,
probe_cluster_id);
}
}
if (!is_retransmit && !send_over_rtx) {
UpdateDelayStatistics(capture_time_ms, now_ms);
UpdateOnSendPacket(options.packet_id, capture_time_ms, rtp_header.ssrc);
}
bool ret = SendPacketToNetwork(buffer_to_send_ptr, length, options);
if (ret) {
rtc::CritScope lock(&send_critsect_);
media_has_been_sent_ = true;
}
UpdateRtpStats(buffer_to_send_ptr, length, rtp_header, send_over_rtx,
is_retransmit);
return ret;
}
void RTPSender::UpdateRtpStats(const uint8_t* buffer,
size_t packet_length,
const RTPHeader& header,
bool is_rtx,
bool is_retransmit) {
StreamDataCounters* counters;
// Get ssrc before taking statistics_crit_ to avoid possible deadlock.
uint32_t ssrc = is_rtx ? RtxSsrc() : SSRC();
rtc::CritScope lock(&statistics_crit_);
if (is_rtx) {
counters = &rtx_rtp_stats_;
} else {
counters = &rtp_stats_;
}
total_bitrate_sent_.Update(packet_length);
if (counters->first_packet_time_ms == -1) {
counters->first_packet_time_ms = clock_->TimeInMilliseconds();
}
if (IsFecPacket(buffer, header)) {
counters->fec.AddPacket(packet_length, header);
}
if (is_retransmit) {
counters->retransmitted.AddPacket(packet_length, header);
}
counters->transmitted.AddPacket(packet_length, header);
if (rtp_stats_callback_) {
rtp_stats_callback_->DataCountersUpdated(*counters, ssrc);
}
}
bool RTPSender::IsFecPacket(const uint8_t* buffer,
const RTPHeader& header) const {
if (!video_) {
return false;
}
bool fec_enabled;
uint8_t pt_red;
uint8_t pt_fec;
video_->GenericFECStatus(&fec_enabled, &pt_red, &pt_fec);
return fec_enabled &&
header.payloadType == pt_red &&
buffer[header.headerLength] == pt_fec;
}
size_t RTPSender::TimeToSendPadding(size_t bytes, int probe_cluster_id) {
if (audio_configured_ || bytes == 0)
return 0;
size_t bytes_sent = TrySendRedundantPayloads(bytes, probe_cluster_id);
if (bytes_sent < bytes)
bytes_sent +=
SendPadData(bytes - bytes_sent, false, 0, 0, probe_cluster_id);
return bytes_sent;
}
// TODO(pwestin): send in the RtpHeaderParser to avoid parsing it again.
int32_t RTPSender::SendToNetwork(uint8_t* buffer,
size_t payload_length,
size_t rtp_header_length,
int64_t capture_time_ms,
StorageType storage,
RtpPacketSender::Priority priority) {
size_t length = payload_length + rtp_header_length;
RtpUtility::RtpHeaderParser rtp_parser(buffer, length);
RTPHeader rtp_header;
rtp_parser.Parse(&rtp_header);
int64_t now_ms = clock_->TimeInMilliseconds();
// |capture_time_ms| <= 0 is considered invalid.
// TODO(holmer): This should be changed all over Video Engine so that negative
// time is consider invalid, while 0 is considered a valid time.
if (capture_time_ms > 0) {
UpdateTransmissionTimeOffset(buffer, length, rtp_header,
now_ms - capture_time_ms);
}
UpdateAbsoluteSendTime(buffer, length, rtp_header, now_ms);
// Used for NACK and to spread out the transmission of packets.
if (packet_history_.PutRTPPacket(buffer, length, capture_time_ms, storage) !=
0) {
return -1;
}
if (paced_sender_) {
// Correct offset between implementations of millisecond time stamps in
// TickTime and Clock.
int64_t corrected_time_ms = capture_time_ms + clock_delta_ms_;
paced_sender_->InsertPacket(priority, rtp_header.ssrc,
rtp_header.sequenceNumber, corrected_time_ms,
payload_length, false);
if (last_capture_time_ms_sent_ == 0 ||
corrected_time_ms > last_capture_time_ms_sent_) {
last_capture_time_ms_sent_ = corrected_time_ms;
TRACE_EVENT_ASYNC_BEGIN1(TRACE_DISABLED_BY_DEFAULT("webrtc_rtp"),
"PacedSend", corrected_time_ms,
"capture_time_ms", corrected_time_ms);
}
return 0;
}
PacketOptions options;
if (AllocateTransportSequenceNumber(&options.packet_id)) {
if (UpdateTransportSequenceNumber(options.packet_id, buffer, length,
rtp_header)) {
if (transport_feedback_observer_)
transport_feedback_observer_->AddPacket(options.packet_id, length, true,
PacketInfo::kNotAProbe);
}
}
UpdateDelayStatistics(capture_time_ms, now_ms);
UpdateOnSendPacket(options.packet_id, capture_time_ms, rtp_header.ssrc);
bool sent = SendPacketToNetwork(buffer, length, options);
// Mark the packet as sent in the history even if send failed. Dropping a
// packet here should be treated as any other packet drop so we should be
// ready for a retransmission.
packet_history_.SetSent(rtp_header.sequenceNumber);
if (!sent)
return -1;
{
rtc::CritScope lock(&send_critsect_);
media_has_been_sent_ = true;
}
UpdateRtpStats(buffer, length, rtp_header, false, false);
return 0;
}
void RTPSender::UpdateDelayStatistics(int64_t capture_time_ms, int64_t now_ms) {
if (!send_side_delay_observer_ || capture_time_ms <= 0)
return;
uint32_t ssrc;
int avg_delay_ms = 0;
int max_delay_ms = 0;
{
rtc::CritScope lock(&send_critsect_);
ssrc = ssrc_;
}
{
rtc::CritScope cs(&statistics_crit_);
// TODO(holmer): Compute this iteratively instead.
send_delays_[now_ms] = now_ms - capture_time_ms;
send_delays_.erase(send_delays_.begin(),
send_delays_.lower_bound(now_ms -
kSendSideDelayWindowMs));
int num_delays = 0;
for (auto it = send_delays_.upper_bound(now_ms - kSendSideDelayWindowMs);
it != send_delays_.end(); ++it) {
max_delay_ms = std::max(max_delay_ms, it->second);
avg_delay_ms += it->second;
++num_delays;
}
if (num_delays == 0)
return;
avg_delay_ms = (avg_delay_ms + num_delays / 2) / num_delays;
}
send_side_delay_observer_->SendSideDelayUpdated(avg_delay_ms, max_delay_ms,
ssrc);
}
void RTPSender::UpdateOnSendPacket(int packet_id,
int64_t capture_time_ms,
uint32_t ssrc) {
if (!send_packet_observer_ || capture_time_ms <= 0 || packet_id == -1)
return;
send_packet_observer_->OnSendPacket(packet_id, capture_time_ms, ssrc);
}
void RTPSender::ProcessBitrate() {
rtc::CritScope lock(&send_critsect_);
total_bitrate_sent_.Process();
nack_bitrate_.Process();
if (audio_configured_) {
return;
}
video_->ProcessBitrate();
}
size_t RTPSender::RtpHeaderLength() const {
rtc::CritScope lock(&send_critsect_);
size_t rtp_header_length = kRtpHeaderLength;
rtp_header_length += sizeof(uint32_t) * csrcs_.size();
rtp_header_length += RtpHeaderExtensionLength();
return rtp_header_length;
}
uint16_t RTPSender::AllocateSequenceNumber(uint16_t packets_to_send) {
rtc::CritScope lock(&send_critsect_);
uint16_t first_allocated_sequence_number = sequence_number_;
sequence_number_ += packets_to_send;
return first_allocated_sequence_number;
}
void RTPSender::GetDataCounters(StreamDataCounters* rtp_stats,
StreamDataCounters* rtx_stats) const {
rtc::CritScope lock(&statistics_crit_);
*rtp_stats = rtp_stats_;
*rtx_stats = rtx_rtp_stats_;
}
size_t RTPSender::CreateRtpHeader(uint8_t* header,
int8_t payload_type,
uint32_t ssrc,
bool marker_bit,
uint32_t timestamp,
uint16_t sequence_number,
const std::vector<uint32_t>& csrcs) const {
header[0] = 0x80; // version 2.
header[1] = static_cast<uint8_t>(payload_type);
if (marker_bit) {
header[1] |= kRtpMarkerBitMask; // Marker bit is set.
}
ByteWriter<uint16_t>::WriteBigEndian(header + 2, sequence_number);
ByteWriter<uint32_t>::WriteBigEndian(header + 4, timestamp);
ByteWriter<uint32_t>::WriteBigEndian(header + 8, ssrc);
int32_t rtp_header_length = kRtpHeaderLength;
if (csrcs.size() > 0) {
uint8_t* ptr = &header[rtp_header_length];
for (size_t i = 0; i < csrcs.size(); ++i) {
ByteWriter<uint32_t>::WriteBigEndian(ptr, csrcs[i]);
ptr += 4;
}
header[0] = (header[0] & 0xf0) | csrcs.size();
// Update length of header.
rtp_header_length += sizeof(uint32_t) * csrcs.size();
}
uint16_t len =
BuildRTPHeaderExtension(header + rtp_header_length, marker_bit);
if (len > 0) {
header[0] |= 0x10; // Set extension bit.
rtp_header_length += len;
}
return rtp_header_length;
}
int32_t RTPSender::BuildRTPheader(uint8_t* data_buffer,
int8_t payload_type,
bool marker_bit,
uint32_t capture_timestamp,
int64_t capture_time_ms,
bool timestamp_provided,
bool inc_sequence_number) {
assert(payload_type >= 0);
rtc::CritScope lock(&send_critsect_);
if (timestamp_provided) {
timestamp_ = start_timestamp_ + capture_timestamp;
} else {
// Make a unique time stamp.
// We can't inc by the actual time, since then we increase the risk of back
// timing.
timestamp_++;
}
last_timestamp_time_ms_ = clock_->TimeInMilliseconds();
uint32_t sequence_number = sequence_number_++;
capture_time_ms_ = capture_time_ms;
last_packet_marker_bit_ = marker_bit;
return CreateRtpHeader(data_buffer, payload_type, ssrc_, marker_bit,
timestamp_, sequence_number, csrcs_);
}
uint16_t RTPSender::BuildRTPHeaderExtension(uint8_t* data_buffer,
bool marker_bit) const {
if (rtp_header_extension_map_.Size() <= 0) {
return 0;
}
// RTP header extension, RFC 3550.
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | defined by profile | length |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | header extension |
// | .... |
//
const uint32_t kPosLength = 2;
const uint32_t kHeaderLength = kRtpOneByteHeaderLength;
// Add extension ID (0xBEDE).
ByteWriter<uint16_t>::WriteBigEndian(data_buffer,
kRtpOneByteHeaderExtensionId);
// Add extensions.
uint16_t total_block_length = 0;
RTPExtensionType type = rtp_header_extension_map_.First();
while (type != kRtpExtensionNone) {
uint8_t block_length = 0;
uint8_t* extension_data = &data_buffer[kHeaderLength + total_block_length];
switch (type) {
case kRtpExtensionTransmissionTimeOffset:
block_length = BuildTransmissionTimeOffsetExtension(extension_data);
break;
case kRtpExtensionAudioLevel:
block_length = BuildAudioLevelExtension(extension_data);
break;
case kRtpExtensionAbsoluteSendTime:
block_length = BuildAbsoluteSendTimeExtension(extension_data);
break;
case kRtpExtensionVideoRotation:
block_length = BuildVideoRotationExtension(extension_data);
break;
case kRtpExtensionTransportSequenceNumber:
block_length = BuildTransportSequenceNumberExtension(
extension_data, transport_sequence_number_);
break;
case kRtpExtensionPlayoutDelay:
block_length = BuildPlayoutDelayExtension(
extension_data, playout_delay_oracle_.min_playout_delay_ms(),
playout_delay_oracle_.max_playout_delay_ms());
break;
default:
assert(false);
}
total_block_length += block_length;
type = rtp_header_extension_map_.Next(type);
}
if (total_block_length == 0) {
// No extension added.
return 0;
}
// Add padding elements until we've filled a 32 bit block.
size_t padding_bytes =
RtpUtility::Word32Align(total_block_length) - total_block_length;
if (padding_bytes > 0) {
memset(&data_buffer[kHeaderLength + total_block_length], 0, padding_bytes);
total_block_length += padding_bytes;
}
// Set header length (in number of Word32, header excluded).
ByteWriter<uint16_t>::WriteBigEndian(data_buffer + kPosLength,
total_block_length / 4);
// Total added length.
return kHeaderLength + total_block_length;
}
uint8_t RTPSender::BuildTransmissionTimeOffsetExtension(
uint8_t* data_buffer) const {
// From RFC 5450: Transmission Time Offsets in RTP Streams.
//
// The transmission time is signaled to the receiver in-band using the
// general mechanism for RTP header extensions [RFC5285]. The payload
// of this extension (the transmitted value) is a 24-bit signed integer.
// When added to the RTP timestamp of the packet, it represents the
// "effective" RTP transmission time of the packet, on the RTP
// timescale.
//
// The form of the transmission offset extension block:
//
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | len=2 | transmission offset |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Get id defined by user.
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionTransmissionTimeOffset,
&id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 2;
data_buffer[pos++] = (id << 4) + len;
ByteWriter<int32_t, 3>::WriteBigEndian(data_buffer + pos,
transmission_time_offset_);
pos += 3;
assert(pos == kTransmissionTimeOffsetLength);
return kTransmissionTimeOffsetLength;
}
uint8_t RTPSender::BuildAudioLevelExtension(uint8_t* data_buffer) const {
// An RTP Header Extension for Client-to-Mixer Audio Level Indication
//
// https://datatracker.ietf.org/doc/draft-lennox-avt-rtp-audio-level-exthdr/
//
// The form of the audio level extension block:
//
// 0 1
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | len=0 |V| level |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Get id defined by user.
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionAudioLevel, &id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 0;
data_buffer[pos++] = (id << 4) + len;
data_buffer[pos++] = (1 << 7) + 0; // Voice, 0 dBov.
assert(pos == kAudioLevelLength);
return kAudioLevelLength;
}
uint8_t RTPSender::BuildAbsoluteSendTimeExtension(uint8_t* data_buffer) const {
// Absolute send time in RTP streams.
//
// The absolute send time is signaled to the receiver in-band using the
// general mechanism for RTP header extensions [RFC5285]. The payload
// of this extension (the transmitted value) is a 24-bit unsigned integer
// containing the sender's current time in seconds as a fixed point number
// with 18 bits fractional part.
//
// The form of the absolute send time extension block:
//
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | len=2 | absolute send time |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Get id defined by user.
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionAbsoluteSendTime,
&id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 2;
data_buffer[pos++] = (id << 4) + len;
ByteWriter<uint32_t, 3>::WriteBigEndian(data_buffer + pos,
absolute_send_time_);
pos += 3;
assert(pos == kAbsoluteSendTimeLength);
return kAbsoluteSendTimeLength;
}
uint8_t RTPSender::BuildVideoRotationExtension(uint8_t* data_buffer) const {
// Coordination of Video Orientation in RTP streams.
//
// Coordination of Video Orientation consists in signaling of the current
// orientation of the image captured on the sender side to the receiver for
// appropriate rendering and displaying.
//
// 0 1
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | len=0 |0 0 0 0 C F R R|
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Get id defined by user.
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionVideoRotation, &id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 0;
data_buffer[pos++] = (id << 4) + len;
data_buffer[pos++] = ConvertVideoRotationToCVOByte(rotation_);
assert(pos == kVideoRotationLength);
return kVideoRotationLength;
}
uint8_t RTPSender::BuildTransportSequenceNumberExtension(
uint8_t* data_buffer,
uint16_t sequence_number) const {
// 0 1 2
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | L=1 |transport wide sequence number |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Get id defined by user.
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionTransportSequenceNumber,
&id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 1;
data_buffer[pos++] = (id << 4) + len;
ByteWriter<uint16_t>::WriteBigEndian(data_buffer + pos, sequence_number);
pos += 2;
assert(pos == kTransportSequenceNumberLength);
return kTransportSequenceNumberLength;
}
uint8_t RTPSender::BuildPlayoutDelayExtension(
uint8_t* data_buffer,
uint16_t min_playout_delay_ms,
uint16_t max_playout_delay_ms) const {
RTC_DCHECK_LE(min_playout_delay_ms, kPlayoutDelayMaxMs);
RTC_DCHECK_LE(max_playout_delay_ms, kPlayoutDelayMaxMs);
RTC_DCHECK_LE(min_playout_delay_ms, max_playout_delay_ms);
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// | ID | len=2 | MIN delay | MAX delay |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
uint8_t id;
if (rtp_header_extension_map_.GetId(kRtpExtensionPlayoutDelay, &id) != 0) {
// Not registered.
return 0;
}
size_t pos = 0;
const uint8_t len = 2;
// Convert MS to value to be sent on extension header.
uint16_t min_playout = min_playout_delay_ms / kPlayoutDelayGranularityMs;
uint16_t max_playout = max_playout_delay_ms / kPlayoutDelayGranularityMs;
data_buffer[pos++] = (id << 4) + len;
data_buffer[pos++] = min_playout >> 4;
data_buffer[pos++] = ((min_playout & 0xf) << 4) | (max_playout >> 8);
data_buffer[pos++] = max_playout & 0xff;
assert(pos == kPlayoutDelayLength);
return kPlayoutDelayLength;
}
bool RTPSender::FindHeaderExtensionPosition(RTPExtensionType type,
const uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
size_t* position) const {
// Get length until start of header extension block.
int extension_block_pos =
rtp_header_extension_map_.GetLengthUntilBlockStartInBytes(type);
if (extension_block_pos < 0) {
LOG(LS_WARNING) << "Failed to find extension position for " << type
<< " as it is not registered.";
return false;
}
HeaderExtension header_extension(type);
size_t extension_pos =
kRtpHeaderLength + rtp_header.numCSRCs * sizeof(uint32_t);
size_t block_pos = extension_pos + extension_block_pos;
if (rtp_packet_length < block_pos + header_extension.length ||
rtp_header.headerLength < block_pos + header_extension.length) {
LOG(LS_WARNING) << "Failed to find extension position for " << type
<< " as the length is invalid.";
return false;
}
// Verify that header contains extension.
if (!(rtp_packet[extension_pos] == 0xBE &&
rtp_packet[extension_pos + 1] == 0xDE)) {
LOG(LS_WARNING) << "Failed to find extension position for " << type
<< "as hdr extension not found.";
return false;
}
*position = block_pos;
return true;
}
RTPSender::ExtensionStatus RTPSender::VerifyExtension(
RTPExtensionType extension_type,
uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
size_t extension_length_bytes,
size_t* extension_offset) const {
// Get id.
uint8_t id = 0;
if (rtp_header_extension_map_.GetId(extension_type, &id) != 0)
return ExtensionStatus::kNotRegistered;
size_t block_pos = 0;
if (!FindHeaderExtensionPosition(extension_type, rtp_packet,
rtp_packet_length, rtp_header, &block_pos))
return ExtensionStatus::kError;
// Verify first byte in block.
const uint8_t first_block_byte = (id << 4) + (extension_length_bytes - 2);
if (rtp_packet[block_pos] != first_block_byte)
return ExtensionStatus::kError;
*extension_offset = block_pos;
return ExtensionStatus::kOk;
}
void RTPSender::UpdateTransmissionTimeOffset(uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
int64_t time_diff_ms) const {
size_t offset;
rtc::CritScope lock(&send_critsect_);
switch (VerifyExtension(kRtpExtensionTransmissionTimeOffset, rtp_packet,
rtp_packet_length, rtp_header,
kTransmissionTimeOffsetLength, &offset)) {
case ExtensionStatus::kNotRegistered:
return;
case ExtensionStatus::kError:
LOG(LS_WARNING) << "Failed to update transmission time offset.";
return;
case ExtensionStatus::kOk:
break;
default:
RTC_NOTREACHED();
}
// Update transmission offset field (converting to a 90 kHz timestamp).
ByteWriter<int32_t, 3>::WriteBigEndian(rtp_packet + offset + 1,
time_diff_ms * 90); // RTP timestamp.
}
bool RTPSender::UpdateAudioLevel(uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
bool is_voiced,
uint8_t dBov) const {
size_t offset;
rtc::CritScope lock(&send_critsect_);
switch (VerifyExtension(kRtpExtensionAudioLevel, rtp_packet,
rtp_packet_length, rtp_header, kAudioLevelLength,
&offset)) {
case ExtensionStatus::kNotRegistered:
return false;
case ExtensionStatus::kError:
LOG(LS_WARNING) << "Failed to update audio level.";
return false;
case ExtensionStatus::kOk:
break;
default:
RTC_NOTREACHED();
}
rtp_packet[offset + 1] = (is_voiced ? 0x80 : 0x00) + (dBov & 0x7f);
return true;
}
bool RTPSender::UpdateVideoRotation(uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
VideoRotation rotation) const {
size_t offset;
rtc::CritScope lock(&send_critsect_);
switch (VerifyExtension(kRtpExtensionVideoRotation, rtp_packet,
rtp_packet_length, rtp_header, kVideoRotationLength,
&offset)) {
case ExtensionStatus::kNotRegistered:
return false;
case ExtensionStatus::kError:
LOG(LS_WARNING) << "Failed to update CVO.";
return false;
case ExtensionStatus::kOk:
break;
default:
RTC_NOTREACHED();
}
rtp_packet[offset + 1] = ConvertVideoRotationToCVOByte(rotation);
return true;
}
void RTPSender::UpdateAbsoluteSendTime(uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header,
int64_t now_ms) const {
size_t offset;
rtc::CritScope lock(&send_critsect_);
switch (VerifyExtension(kRtpExtensionAbsoluteSendTime, rtp_packet,
rtp_packet_length, rtp_header,
kAbsoluteSendTimeLength, &offset)) {
case ExtensionStatus::kNotRegistered:
return;
case ExtensionStatus::kError:
LOG(LS_WARNING) << "Failed to update absolute send time";
return;
case ExtensionStatus::kOk:
break;
default:
RTC_NOTREACHED();
}
// Update absolute send time field (convert ms to 24-bit unsigned with 18 bit
// fractional part).
ByteWriter<uint32_t, 3>::WriteBigEndian(rtp_packet + offset + 1,
ConvertMsTo24Bits(now_ms));
}
bool RTPSender::UpdateTransportSequenceNumber(
uint16_t sequence_number,
uint8_t* rtp_packet,
size_t rtp_packet_length,
const RTPHeader& rtp_header) const {
size_t offset;
rtc::CritScope lock(&send_critsect_);
switch (VerifyExtension(kRtpExtensionTransportSequenceNumber, rtp_packet,
rtp_packet_length, rtp_header,
kTransportSequenceNumberLength, &offset)) {
case ExtensionStatus::kNotRegistered:
return false;
case ExtensionStatus::kError:
LOG(LS_WARNING) << "Failed to update transport sequence number";
return false;
case ExtensionStatus::kOk:
break;
default:
RTC_NOTREACHED();
}
BuildTransportSequenceNumberExtension(rtp_packet + offset, sequence_number);
return true;
}
bool RTPSender::AllocateTransportSequenceNumber(int* packet_id) const {
if (!transport_sequence_number_allocator_)
return false;
*packet_id = transport_sequence_number_allocator_->AllocateSequenceNumber();
return true;
}
void RTPSender::SetSendingStatus(bool enabled) {
if (enabled) {
uint32_t frequency_hz = SendPayloadFrequency();
uint32_t RTPtime = CurrentRtp(*clock_, frequency_hz);
// Will be ignored if it's already configured via API.
SetStartTimestamp(RTPtime, false);
} else {
rtc::CritScope lock(&send_critsect_);
if (!ssrc_forced_) {
// Generate a new SSRC.
ssrc_db_->ReturnSSRC(ssrc_);
ssrc_ = ssrc_db_->CreateSSRC();
RTC_DCHECK(ssrc_ != 0);
bitrates_.set_ssrc(ssrc_);
}
// Don't initialize seq number if SSRC passed externally.
if (!sequence_number_forced_ && !ssrc_forced_) {
// Generate a new sequence number.
sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber);
}
}
}
void RTPSender::SetSendingMediaStatus(bool enabled) {
rtc::CritScope lock(&send_critsect_);
sending_media_ = enabled;
}
bool RTPSender::SendingMedia() const {
rtc::CritScope lock(&send_critsect_);
return sending_media_;
}
uint32_t RTPSender::Timestamp() const {
rtc::CritScope lock(&send_critsect_);
return timestamp_;
}
void RTPSender::SetStartTimestamp(uint32_t timestamp, bool force) {
rtc::CritScope lock(&send_critsect_);
if (force) {
start_timestamp_forced_ = true;
start_timestamp_ = timestamp;
} else {
if (!start_timestamp_forced_) {
start_timestamp_ = timestamp;
}
}
}
uint32_t RTPSender::StartTimestamp() const {
rtc::CritScope lock(&send_critsect_);
return start_timestamp_;
}
uint32_t RTPSender::GenerateNewSSRC() {
// If configured via API, return 0.
rtc::CritScope lock(&send_critsect_);
if (ssrc_forced_) {
return 0;
}
ssrc_ = ssrc_db_->CreateSSRC();
RTC_DCHECK(ssrc_ != 0);
bitrates_.set_ssrc(ssrc_);
return ssrc_;
}
void RTPSender::SetSSRC(uint32_t ssrc) {
// This is configured via the API.
rtc::CritScope lock(&send_critsect_);
if (ssrc_ == ssrc && ssrc_forced_) {
return; // Since it's same ssrc, don't reset anything.
}
ssrc_forced_ = true;
ssrc_db_->ReturnSSRC(ssrc_);
ssrc_db_->RegisterSSRC(ssrc);
ssrc_ = ssrc;
bitrates_.set_ssrc(ssrc_);
if (!sequence_number_forced_) {
sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber);
}
}
uint32_t RTPSender::SSRC() const {
rtc::CritScope lock(&send_critsect_);
return ssrc_;
}
void RTPSender::SetCsrcs(const std::vector<uint32_t>& csrcs) {
assert(csrcs.size() <= kRtpCsrcSize);
rtc::CritScope lock(&send_critsect_);
csrcs_ = csrcs;
}
void RTPSender::SetSequenceNumber(uint16_t seq) {
rtc::CritScope lock(&send_critsect_);
sequence_number_forced_ = true;
sequence_number_ = seq;
}
uint16_t RTPSender::SequenceNumber() const {
rtc::CritScope lock(&send_critsect_);
return sequence_number_;
}
// Audio.
int32_t RTPSender::SendTelephoneEvent(uint8_t key,
uint16_t time_ms,
uint8_t level) {
if (!audio_configured_) {
return -1;
}
return audio_->SendTelephoneEvent(key, time_ms, level);
}
int32_t RTPSender::SetAudioPacketSize(uint16_t packet_size_samples) {
if (!audio_configured_) {
return -1;
}
return audio_->SetAudioPacketSize(packet_size_samples);
}
int32_t RTPSender::SetAudioLevel(uint8_t level_d_bov) {
return audio_->SetAudioLevel(level_d_bov);
}
int32_t RTPSender::SetRED(int8_t payload_type) {
if (!audio_configured_) {
return -1;
}
return audio_->SetRED(payload_type);
}
int32_t RTPSender::RED(int8_t *payload_type) const {
if (!audio_configured_) {
return -1;
}
return audio_->RED(payload_type);
}
RtpVideoCodecTypes RTPSender::VideoCodecType() const {
assert(!audio_configured_ && "Sender is an audio stream!");
return video_->VideoCodecType();
}
void RTPSender::SetGenericFECStatus(bool enable,
uint8_t payload_type_red,
uint8_t payload_type_fec) {
RTC_DCHECK(!audio_configured_);
video_->SetGenericFECStatus(enable, payload_type_red, payload_type_fec);
}
void RTPSender::GenericFECStatus(bool* enable,
uint8_t* payload_type_red,
uint8_t* payload_type_fec) const {
RTC_DCHECK(!audio_configured_);
video_->GenericFECStatus(enable, payload_type_red, payload_type_fec);
}
int32_t RTPSender::SetFecParameters(
const FecProtectionParams *delta_params,
const FecProtectionParams *key_params) {
if (audio_configured_) {
return -1;
}
video_->SetFecParameters(delta_params, key_params);
return 0;
}
void RTPSender::BuildRtxPacket(uint8_t* buffer, size_t* length,
uint8_t* buffer_rtx) {
rtc::CritScope lock(&send_critsect_);
uint8_t* data_buffer_rtx = buffer_rtx;
// Add RTX header.
RtpUtility::RtpHeaderParser rtp_parser(
reinterpret_cast<const uint8_t*>(buffer), *length);
RTPHeader rtp_header;
rtp_parser.Parse(&rtp_header);
// Add original RTP header.
memcpy(data_buffer_rtx, buffer, rtp_header.headerLength);
// Replace payload type, if a specific type is set for RTX.
auto kv = rtx_payload_type_map_.find(rtp_header.payloadType);
// Use rtx mapping associated with media codec if we can't find one, assuming
// it's red.
// TODO(holmer): Remove once old Chrome versions don't rely on this.
if (kv == rtx_payload_type_map_.end())
kv = rtx_payload_type_map_.find(payload_type_);
if (kv != rtx_payload_type_map_.end())
data_buffer_rtx[1] = kv->second;
if (rtp_header.markerBit)
data_buffer_rtx[1] |= kRtpMarkerBitMask;
// Replace sequence number.
uint8_t* ptr = data_buffer_rtx + 2;
ByteWriter<uint16_t>::WriteBigEndian(ptr, sequence_number_rtx_++);
// Replace SSRC.
ptr += 6;
ByteWriter<uint32_t>::WriteBigEndian(ptr, ssrc_rtx_);
// Add OSN (original sequence number).
ptr = data_buffer_rtx + rtp_header.headerLength;
ByteWriter<uint16_t>::WriteBigEndian(ptr, rtp_header.sequenceNumber);
ptr += 2;
// Add original payload data.
memcpy(ptr, buffer + rtp_header.headerLength,
*length - rtp_header.headerLength);
*length += 2;
}
void RTPSender::RegisterRtpStatisticsCallback(
StreamDataCountersCallback* callback) {
rtc::CritScope cs(&statistics_crit_);
rtp_stats_callback_ = callback;
}
StreamDataCountersCallback* RTPSender::GetRtpStatisticsCallback() const {
rtc::CritScope cs(&statistics_crit_);
return rtp_stats_callback_;
}
uint32_t RTPSender::BitrateSent() const {
return total_bitrate_sent_.BitrateLast();
}
void RTPSender::SetRtpState(const RtpState& rtp_state) {
rtc::CritScope lock(&send_critsect_);
sequence_number_ = rtp_state.sequence_number;
sequence_number_forced_ = true;
timestamp_ = rtp_state.timestamp;
capture_time_ms_ = rtp_state.capture_time_ms;
last_timestamp_time_ms_ = rtp_state.last_timestamp_time_ms;
media_has_been_sent_ = rtp_state.media_has_been_sent;
}
RtpState RTPSender::GetRtpState() const {
rtc::CritScope lock(&send_critsect_);
RtpState state;
state.sequence_number = sequence_number_;
state.start_timestamp = start_timestamp_;
state.timestamp = timestamp_;
state.capture_time_ms = capture_time_ms_;
state.last_timestamp_time_ms = last_timestamp_time_ms_;
state.media_has_been_sent = media_has_been_sent_;
return state;
}
void RTPSender::SetRtxRtpState(const RtpState& rtp_state) {
rtc::CritScope lock(&send_critsect_);
sequence_number_rtx_ = rtp_state.sequence_number;
}
RtpState RTPSender::GetRtxRtpState() const {
rtc::CritScope lock(&send_critsect_);
RtpState state;
state.sequence_number = sequence_number_rtx_;
state.start_timestamp = start_timestamp_;
return state;
}
} // namespace webrtc