Implement disabling and enabling media tracks

media/filters/ffmpeg_demuxer.cc

Index: media/filters/ffmpeg_demuxer.cc
diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index 76ac688f911fd68f56ddc6cbbc8dbc451964f466..f546e670148d54158fb14fd31773fb937fba7fa1 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -272,6 +272,8 @@ FFmpegDemuxerStream::FFmpegDemuxerStream(
       last_packet_timestamp_(kNoTimestamp()),
       last_packet_duration_(kNoTimestamp()),
       video_rotation_(VIDEO_ROTATION_0),
+      is_enabled_(true),
+      waiting_for_keyframe_(false),
       fixup_negative_timestamps_(false) {
   DCHECK(demuxer_);
 
@@ -358,6 +360,13 @@ void FFmpegDemuxerStream::EnqueuePacket(ScopedAVPacket packet) {
     return;
   }
 
+  if (waiting_for_keyframe_) {
+    if (packet.get()->flags & AV_PKT_FLAG_KEY)
+      waiting_for_keyframe_ = false;
+    else
+      return;

[chcunningham, 2016/06/24 23:32:55]

This would be good to DVLOG - "Dropping non-key frame pts:X"

[servolk, 2016/06/25 00:36:33]

Done.

+  }
+
 #if defined(USE_PROPRIETARY_CODECS)
   // Convert the packet if there is a bitstream filter.
   if (packet->data && bitstream_converter_ &&
@@ -618,6 +627,12 @@ void FFmpegDemuxerStream::Read(const ReadCB& read_cb) {
     return;
   }
 
+  if (!is_enabled_) {
+    DVLOG(1) << "Read from disabled stream, returning EOS";
+    base::ResetAndReturn(&read_cb_).Run(kOk, DecoderBuffer::CreateEOSBuffer());
+    return;
+  }
+
   SatisfyPendingRead();
 }
 
@@ -681,6 +696,34 @@ VideoRotation FFmpegDemuxerStream::video_rotation() {
   return video_rotation_;
 }
 
+bool FFmpegDemuxerStream::enabled() const {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  return is_enabled_;
+}
+
+void FFmpegDemuxerStream::set_enabled(bool enabled, base::TimeDelta timestamp) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  if (enabled == is_enabled_)
+    return;
+
+  is_enabled_ = enabled;
+  if (is_enabled_) {
+    waiting_for_keyframe_ = true;
+    if (!stream_restarted_cb_.is_null())
+      stream_restarted_cb_.Run(this, timestamp);
+  }
+  if (!is_enabled_ && !read_cb_.is_null()) {
+    DVLOG(1) << "Read from disabled stream, returning EOS";
+    base::ResetAndReturn(&read_cb_).Run(kOk, DecoderBuffer::CreateEOSBuffer());
+    return;
+  }
+}
+
+void FFmpegDemuxerStream::SetStreamRestartedCB(const StreamRestartedCB& cb) {
+  DCHECK(!cb.is_null());
+  stream_restarted_cb_ = cb;
+}
+
 void FFmpegDemuxerStream::SetLiveness(Liveness liveness) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK_EQ(liveness_, LIVENESS_UNKNOWN);
@@ -1469,6 +1512,34 @@ void FFmpegDemuxer::OnSeekFrameDone(const PipelineStatusCB& cb, int result) {
   cb.Run(PIPELINE_OK);
 }
 
+void FFmpegDemuxer::OnEnabledAudioTracksChanged(
+    const std::vector<MediaTrack::Id>& track_ids,
+    base::TimeDelta currTime) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  bool enabled = false;
+  DemuxerStream* audio_stream = GetStream(DemuxerStream::AUDIO);
+  CHECK(audio_stream);
+  if (track_ids.size() > 0) {
+    // DCHECK(track_id_to_demux_stream_map_[track_ids[0]] == audio_stream);
+    enabled = true;
+  }
+  audio_stream->set_enabled(enabled, currTime);
+}
+
+void FFmpegDemuxer::OnSelectedVideoTrackChanged(
+    const std::vector<MediaTrack::Id>& track_ids,
+    base::TimeDelta currTime) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  bool enabled = false;
+  DemuxerStream* video_stream = GetStream(DemuxerStream::VIDEO);
+  CHECK(video_stream);
+  if (track_ids.size() > 0) {
+    // DCHECK(track_id_to_demux_stream_map_[track_ids[0]] == video_stream);
+    enabled = true;
+  }
+  video_stream->set_enabled(enabled, currTime);
+}
+
 void FFmpegDemuxer::ReadFrameIfNeeded() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
@@ -1556,7 +1627,8 @@ void FFmpegDemuxer::OnReadFrameDone(ScopedAVPacket packet, int result) {
     }
 
     FFmpegDemuxerStream* demuxer_stream = streams_[packet->stream_index];
-    demuxer_stream->EnqueuePacket(std::move(packet));
+    if (demuxer_stream->enabled())
+      demuxer_stream->EnqueuePacket(std::move(packet));
   }
 
   // Keep reading until we've reached capacity.