Reland of Split IncomingVideoStream into two implementations, with smoothing and without.

webrtc/video/video_receive_stream.cc

 /*
  *  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.
  */
 
@@ skipping 126 matching lines @@
   codec.width = 320;
   codec.height = 180;
   codec.startBitrate = codec.minBitrate = codec.maxBitrate =
       Call::Config::kDefaultStartBitrateBps / 1000;
 
   return codec;
 }
 }  // namespace
 
 namespace internal {
+
+// Since an IncomingVideoStream instance will create a thread/queue, we don't
+// instantiate one unless we know we're going to be delivering the frames
+// to a renderer.
+//
+// TODO(tommi): Consider making the functionality provided by the
+// IncomingVideoStream classes, tied to the Config class instead or even higher
+// level.  That will make it an optional feature that will be up to the
+// application to use or not use.  Right now, we have two classes available,
+// they both have threads involved which uses WebRTC's threading classes and
+// that might not suit what the application wants to do.  If one of them or
+// neither, suits, the app can get some code size back as well as more control.
+std::unique_ptr<rtc::VideoSinkInterface<VideoFrame>>
+MaybeCreateIncomingVideoStream(const VideoReceiveStream::Config& config,
+                               rtc::VideoSinkInterface<VideoFrame>* callback) {
+  std::unique_ptr<rtc::VideoSinkInterface<VideoFrame>> ret;
+  if (config.renderer) {
+    if (config.disable_prerenderer_smoothing) {
+      ret.reset(new IncomingVideoStreamNoSmoothing(callback));
+    } else {
+      ret.reset(new IncomingVideoStream(config.render_delay_ms, callback));
+    }
+  }
+  return ret;
+}
+
 VideoReceiveStream::VideoReceiveStream(
     int num_cpu_cores,
     CongestionController* congestion_controller,
     VideoReceiveStream::Config config,
     webrtc::VoiceEngine* voice_engine,
     ProcessThread* process_thread,
     CallStats* call_stats,
     VieRemb* remb)
     : transport_adapter_(config.rtcp_send_transport),
       config_(std::move(config)),
       process_thread_(process_thread),
       clock_(Clock::GetRealTimeClock()),
       decode_thread_(DecodeThreadFunction, this, "DecodingThread"),
       congestion_controller_(congestion_controller),
       call_stats_(call_stats),
       video_receiver_(clock_, nullptr, this, this, this),
-      incoming_video_stream_(config_.disable_prerenderer_smoothing),
       stats_proxy_(&config_, clock_),
       rtp_stream_receiver_(&video_receiver_,
                            congestion_controller_->GetRemoteBitrateEstimator(
                                UseSendSideBwe(config_)),
                            &transport_adapter_,
                            call_stats_->rtcp_rtt_stats(),
                            congestion_controller_->pacer(),
                            congestion_controller_->packet_router(),
                            remb,
                            &config_,
                            &stats_proxy_,
                            process_thread_),
-      video_stream_decoder_(&video_receiver_,
-                            &rtp_stream_receiver_,
-                            &rtp_stream_receiver_,
-                            rtp_stream_receiver_.IsRetransmissionsEnabled(),
-                            rtp_stream_receiver_.IsFecEnabled(),
-                            &stats_proxy_,
-                            &incoming_video_stream_,
-                            config.pre_render_callback),
       vie_sync_(&video_receiver_) {
   LOG(LS_INFO) << "VideoReceiveStream: " << config_.ToString();
 
   RTC_DCHECK(process_thread_);
   RTC_DCHECK(congestion_controller_);
   RTC_DCHECK(call_stats_);
 
-  // Register the channel to receive stats updates.
-  call_stats_->RegisterStatsObserver(&video_stream_decoder_);
-
   RTC_DCHECK(!config_.decoders.empty());
   std::set<int> decoder_payload_types;
   for (const Decoder& decoder : config_.decoders) {
     RTC_CHECK(decoder.decoder);
     RTC_CHECK(decoder_payload_types.find(decoder.payload_type) ==
               decoder_payload_types.end())
         << "Duplicate payload type (" << decoder.payload_type
         << ") for different decoders.";
     decoder_payload_types.insert(decoder.payload_type);
     video_receiver_.RegisterExternalDecoder(decoder.decoder,
                                             decoder.payload_type);
 
     VideoCodec codec = CreateDecoderVideoCodec(decoder);
     RTC_CHECK(rtp_stream_receiver_.SetReceiveCodec(codec));
     RTC_CHECK_EQ(VCM_OK, video_receiver_.RegisterReceiveCodec(
                              &codec, num_cpu_cores, false));
   }
 
   video_receiver_.SetRenderDelay(config.render_delay_ms);
-  incoming_video_stream_.SetExpectedRenderDelay(config.render_delay_ms);
-  incoming_video_stream_.SetExternalCallback(this);
 
   process_thread_->RegisterModule(&video_receiver_);
   process_thread_->RegisterModule(&vie_sync_);
 }
 
 VideoReceiveStream::~VideoReceiveStream() {
   LOG(LS_INFO) << "~VideoReceiveStream: " << config_.ToString();
   Stop();
 
   process_thread_->DeRegisterModule(&vie_sync_);
   process_thread_->DeRegisterModule(&video_receiver_);
 
   // Deregister external decoders so they are no longer running during
   // destruction. This effectively stops the VCM since the decoder thread is
   // stopped, the VCM is deregistered and no asynchronous decoder threads are
   // running.
   for (const Decoder& decoder : config_.decoders)
     video_receiver_.RegisterExternalDecoder(nullptr, decoder.payload_type);
 
-  call_stats_->DeregisterStatsObserver(&video_stream_decoder_);
-
   congestion_controller_->GetRemoteBitrateEstimator(UseSendSideBwe(config_))
       ->RemoveStream(rtp_stream_receiver_.GetRemoteSsrc());
 }
 
 void VideoReceiveStream::SignalNetworkState(NetworkState state) {
   rtp_stream_receiver_.SignalNetworkState(state);
 }
 
 
 bool VideoReceiveStream::DeliverRtcp(const uint8_t* packet, size_t length) {
   return rtp_stream_receiver_.DeliverRtcp(packet, length);
 }
 
 bool VideoReceiveStream::DeliverRtp(const uint8_t* packet,
                                     size_t length,
                                     const PacketTime& packet_time) {
   return rtp_stream_receiver_.DeliverRtp(packet, length, packet_time);
 }
 
 void VideoReceiveStream::Start() {
   if (decode_thread_.IsRunning())
     return;
   transport_adapter_.Enable();
-  incoming_video_stream_.Start();
+  incoming_video_stream_ = MaybeCreateIncomingVideoStream(config_, this);
+  video_stream_decoder_.reset(new VideoStreamDecoder(
+      &video_receiver_, &rtp_stream_receiver_, &rtp_stream_receiver_,
+      rtp_stream_receiver_.IsRetransmissionsEnabled(),
+      rtp_stream_receiver_.IsFecEnabled(), &stats_proxy_,
+      incoming_video_stream_.get(), config_.pre_render_callback));
+  // Register the channel to receive stats updates.
+  call_stats_->RegisterStatsObserver(video_stream_decoder_.get());
   // Start the decode thread
   decode_thread_.Start();
   decode_thread_.SetPriority(rtc::kHighestPriority);
   rtp_stream_receiver_.StartReceive();
 }
 
 void VideoReceiveStream::Stop() {
-  incoming_video_stream_.Stop();
   rtp_stream_receiver_.StopReceive();
   video_receiver_.TriggerDecoderShutdown();
   decode_thread_.Stop();
+  call_stats_->DeregisterStatsObserver(video_stream_decoder_.get());
+  video_stream_decoder_.reset();
+  incoming_video_stream_.reset();
   transport_adapter_.Disable();
 }
 
 void VideoReceiveStream::SetSyncChannel(VoiceEngine* voice_engine,
                                         int audio_channel_id) {
   if (voice_engine && audio_channel_id != -1) {
     VoEVideoSync* voe_sync_interface = VoEVideoSync::GetInterface(voice_engine);
     vie_sync_.ConfigureSync(audio_channel_id, voe_sync_interface,
                             rtp_stream_receiver_.rtp_rtcp(),
                             rtp_stream_receiver_.GetRtpReceiver());
     voe_sync_interface->Release();
   } else {
     vie_sync_.ConfigureSync(-1, nullptr, rtp_stream_receiver_.rtp_rtcp(),
                             rtp_stream_receiver_.GetRtpReceiver());
   }
 }
 
 VideoReceiveStream::Stats VideoReceiveStream::GetStats() const {
   return stats_proxy_.GetStats();
 }
 
+// TODO(tommi): This method grabs a lock 6 times.
 void VideoReceiveStream::OnFrame(const VideoFrame& video_frame) {
+  // TODO(tommi): OnDecodedFrame grabs a lock, incidentally the same lock
+  // that OnSyncOffsetUpdated() and OnRenderedFrame() below grab.
   stats_proxy_.OnDecodedFrame();
 
   int64_t sync_offset_ms;
-  if (vie_sync_.GetStreamSyncOffsetInMs(video_frame, &sync_offset_ms))
+  // TODO(tommi): GetStreamSyncOffsetInMs grabs three locks.  One inside the
+  // function itself, another in GetChannel() and a third in
+  // GetPlayoutTimestamp.  Seems excessive.  Anyhow, I'm assuming the function
+  // succeeds most of the time, which leads to grabbing a fourth lock.
+  if (vie_sync_.GetStreamSyncOffsetInMs(video_frame, &sync_offset_ms)) {
+    // TODO(tommi): OnSyncOffsetUpdated grabs a lock.
     stats_proxy_.OnSyncOffsetUpdated(sync_offset_ms);
+  }
 
-  if (config_.renderer)
-    config_.renderer->OnFrame(video_frame);
+  // config_.renderer must never be null if we're getting this callback.
+  config_.renderer->OnFrame(video_frame);
 
+  // TODO(tommi): OnRenderFrame grabs a lock too.
   stats_proxy_.OnRenderedFrame(video_frame.width(), video_frame.height());
 }
 
 // TODO(asapersson): Consider moving callback from video_encoder.h or
 // creating a different callback.
 int32_t VideoReceiveStream::Encoded(
     const EncodedImage& encoded_image,
     const CodecSpecificInfo* codec_specific_info,
     const RTPFragmentationHeader* fragmentation) {
   stats_proxy_.OnPreDecode(encoded_image, codec_specific_info);
@@ skipping 33 matching lines @@
     const std::vector<uint16_t>& sequence_numbers) {
   rtp_stream_receiver_.RequestPacketRetransmit(sequence_numbers);
 }
 
 void VideoReceiveStream::RequestKeyFrame() {
   rtp_stream_receiver_.RequestKeyFrame();
 }
 
 }  // namespace internal
 }  // namespace webrtc