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/*
* Copyright (c) 2013 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 <stddef.h>
#include <cstdint>
#include <vector>
#include "api/rtp_headers.h"
#include "api/sequence_checker.h"
#include "api/video_codecs/video_codec.h"
#include "api/video_codecs/video_decoder.h"
#include "modules/video_coding/decoder_database.h"
#include "modules/video_coding/deprecated/jitter_buffer.h"
#include "modules/video_coding/deprecated/packet.h"
#include "modules/video_coding/deprecated/receiver.h"
#include "modules/video_coding/encoded_frame.h"
#include "modules/video_coding/generic_decoder.h"
#include "modules/video_coding/include/video_coding.h"
#include "modules/video_coding/include/video_coding_defines.h"
#include "modules/video_coding/internal_defines.h"
#include "modules/video_coding/media_opt_util.h"
#include "modules/video_coding/timing/timing.h"
#include "modules/video_coding/video_coding_impl.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#include "rtc_base/one_time_event.h"
#include "rtc_base/trace_event.h"
#include "system_wrappers/include/clock.h"
namespace webrtc {
namespace vcm {
VideoReceiver::VideoReceiver(Clock* clock,
VCMTiming* timing,
const FieldTrialsView& field_trials)
: clock_(clock),
_timing(timing),
_receiver(_timing, clock_, field_trials),
_decodedFrameCallback(_timing, clock_, field_trials),
_frameTypeCallback(nullptr),
_packetRequestCallback(nullptr),
_scheduleKeyRequest(false),
drop_frames_until_keyframe_(false),
max_nack_list_size_(0),
_codecDataBase(),
_retransmissionTimer(10, clock_),
_keyRequestTimer(500, clock_) {
decoder_thread_checker_.Detach();
module_thread_checker_.Detach();
}
VideoReceiver::~VideoReceiver() {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
}
void VideoReceiver::Process() {
RTC_DCHECK_RUN_ON(&module_thread_checker_);
// Key frame requests
if (_keyRequestTimer.TimeUntilProcess() == 0) {
_keyRequestTimer.Processed();
bool request_key_frame = _frameTypeCallback != nullptr;
if (request_key_frame) {
MutexLock lock(&process_mutex_);
request_key_frame = _scheduleKeyRequest;
}
if (request_key_frame)
RequestKeyFrame();
}
// Packet retransmission requests
// TODO(holmer): Add API for changing Process interval and make sure it's
// disabled when NACK is off.
if (_retransmissionTimer.TimeUntilProcess() == 0) {
_retransmissionTimer.Processed();
bool callback_registered = _packetRequestCallback != nullptr;
uint16_t length = max_nack_list_size_;
if (callback_registered && length > 0) {
// Collect sequence numbers from the default receiver.
bool request_key_frame = false;
std::vector<uint16_t> nackList = _receiver.NackList(&request_key_frame);
int32_t ret = VCM_OK;
if (request_key_frame) {
ret = RequestKeyFrame();
}
if (ret == VCM_OK && !nackList.empty()) {
MutexLock lock(&process_mutex_);
if (_packetRequestCallback != nullptr) {
_packetRequestCallback->ResendPackets(&nackList[0], nackList.size());
}
}
}
}
}
// Register a receive callback. Will be called whenever there is a new frame
// ready for rendering.
int32_t VideoReceiver::RegisterReceiveCallback(
VCMReceiveCallback* receiveCallback) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
// This value is set before the decoder thread starts and unset after
// the decoder thread has been stopped.
_decodedFrameCallback.SetUserReceiveCallback(receiveCallback);
return VCM_OK;
}
// Register an externally defined decoder object.
void VideoReceiver::RegisterExternalDecoder(VideoDecoder* externalDecoder,
uint8_t payloadType) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
if (externalDecoder == nullptr) {
RTC_CHECK(_codecDataBase.DeregisterExternalDecoder(payloadType));
return;
}
_codecDataBase.RegisterExternalDecoder(payloadType, externalDecoder);
}
// Register a frame type request callback.
int32_t VideoReceiver::RegisterFrameTypeCallback(
VCMFrameTypeCallback* frameTypeCallback) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
// This callback is used on the module thread, but since we don't get
// callbacks on the module thread while the decoder thread isn't running
// (and this function must not be called when the decoder is running),
// we don't need a lock here.
_frameTypeCallback = frameTypeCallback;
return VCM_OK;
}
int32_t VideoReceiver::RegisterPacketRequestCallback(
VCMPacketRequestCallback* callback) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
// This callback is used on the module thread, but since we don't get
// callbacks on the module thread while the decoder thread isn't running
// (and this function must not be called when the decoder is running),
// we don't need a lock here.
_packetRequestCallback = callback;
return VCM_OK;
}
// Decode next frame, blocking.
// Should be called as often as possible to get the most out of the decoder.
int32_t VideoReceiver::Decode(uint16_t maxWaitTimeMs) {
RTC_DCHECK_RUN_ON(&decoder_thread_checker_);
VCMEncodedFrame* frame = _receiver.FrameForDecoding(maxWaitTimeMs, true);
if (!frame)
return VCM_FRAME_NOT_READY;
bool drop_frame = false;
{
MutexLock lock(&process_mutex_);
if (drop_frames_until_keyframe_) {
// Still getting delta frames, schedule another keyframe request as if
// decode failed.
if (frame->FrameType() != VideoFrameType::kVideoFrameKey) {
drop_frame = true;
_scheduleKeyRequest = true;
} else {
drop_frames_until_keyframe_ = false;
}
}
}
if (drop_frame) {
_receiver.ReleaseFrame(frame);
return VCM_FRAME_NOT_READY;
}
// If this frame was too late, we should adjust the delay accordingly
if (frame->RenderTimeMs() > 0)
_timing->UpdateCurrentDelay(Timestamp::Millis(frame->RenderTimeMs()),
clock_->CurrentTime());
if (first_frame_received_()) {
RTC_LOG(LS_INFO) << "Received first complete decodable video frame";
}
const int32_t ret = Decode(*frame);
_receiver.ReleaseFrame(frame);
return ret;
}
int32_t VideoReceiver::RequestKeyFrame() {
RTC_DCHECK_RUN_ON(&module_thread_checker_);
TRACE_EVENT0("webrtc", "RequestKeyFrame");
if (_frameTypeCallback != nullptr) {
const int32_t ret = _frameTypeCallback->RequestKeyFrame();
if (ret < 0) {
return ret;
}
MutexLock lock(&process_mutex_);
_scheduleKeyRequest = false;
} else {
return VCM_MISSING_CALLBACK;
}
return VCM_OK;
}
// Must be called from inside the receive side critical section.
int32_t VideoReceiver::Decode(const VCMEncodedFrame& frame) {
RTC_DCHECK_RUN_ON(&decoder_thread_checker_);
TRACE_EVENT0("webrtc", "VideoReceiver::Decode");
// Change decoder if payload type has changed
VCMGenericDecoder* decoder =
_codecDataBase.GetDecoder(frame, &_decodedFrameCallback);
if (decoder == nullptr) {
return VCM_NO_CODEC_REGISTERED;
}
return decoder->Decode(frame, clock_->CurrentTime());
}
// Register possible receive codecs, can be called multiple times
void VideoReceiver::RegisterReceiveCodec(
uint8_t payload_type,
const VideoDecoder::Settings& settings) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
_codecDataBase.RegisterReceiveCodec(payload_type, settings);
}
// Incoming packet from network parsed and ready for decode, non blocking.
int32_t VideoReceiver::IncomingPacket(const uint8_t* incomingPayload,
size_t payloadLength,
const RTPHeader& rtp_header,
const RTPVideoHeader& video_header) {
RTC_DCHECK_RUN_ON(&module_thread_checker_);
if (video_header.frame_type == VideoFrameType::kVideoFrameKey) {
TRACE_EVENT1("webrtc", "VCM::PacketKeyFrame", "seqnum",
rtp_header.sequenceNumber);
}
if (incomingPayload == nullptr) {
// The jitter buffer doesn't handle non-zero payload lengths for packets
// without payload.
// TODO(holmer): We should fix this in the jitter buffer.
payloadLength = 0;
}
// Callers don't provide any ntp time.
const VCMPacket packet(incomingPayload, payloadLength, rtp_header,
video_header, /*ntp_time_ms=*/0,
clock_->CurrentTime());
int32_t ret = _receiver.InsertPacket(packet);
// TODO(holmer): Investigate if this somehow should use the key frame
// request scheduling to throttle the requests.
if (ret == VCM_FLUSH_INDICATOR) {
{
MutexLock lock(&process_mutex_);
drop_frames_until_keyframe_ = true;
}
RequestKeyFrame();
} else if (ret < 0) {
return ret;
}
return VCM_OK;
}
void VideoReceiver::SetNackSettings(size_t max_nack_list_size,
int max_packet_age_to_nack,
int max_incomplete_time_ms) {
RTC_DCHECK_RUN_ON(&construction_thread_checker_);
if (max_nack_list_size != 0) {
max_nack_list_size_ = max_nack_list_size;
}
_receiver.SetNackSettings(max_nack_list_size, max_packet_age_to_nack,
max_incomplete_time_ms);
}
} // namespace vcm
} // namespace webrtc