src/content/renderer/media/media_stream_video_track.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/renderer/media/media_stream_video_track.h"
   6
   7 #include "base/bind.h"
   8 #include "content/renderer/media/video_frame_deliverer.h"
   9 #include "media/base/bind_to_current_loop.h"
  10
  11 namespace content {
  12
  13 // Helper class used for delivering video frames to MediaStreamSinks on the
  14 // IO-thread.
  15 // Frames are delivered to an instance of this class from a
  16 // MediaStreamVideoSource on the IO-thread to the method DeliverFrameOnIO.
  17 // Frames are only delivered to the sinks if the track is enabled.
  18 class MediaStreamVideoTrack::FrameDeliverer : public VideoFrameDeliverer {
  19  public:
  20   FrameDeliverer(
  21       const scoped_refptr<base::MessageLoopProxy>& io_message_loop_proxy,
  22       bool enabled)
  23       : VideoFrameDeliverer(io_message_loop_proxy),
  24         enabled_(enabled) {
  25   }
  26
  27   // Add |sink| to receive state changes on the main render thread.
  28   // Video frames will be delivered to |callback| on the IO thread.
  29   void AddSink(MediaStreamVideoSink* sink,
  30                const VideoCaptureDeliverFrameCB& callback) {
  31     DCHECK(thread_checker().CalledOnValidThread());
  32     DCHECK(std::find(sinks_.begin(), sinks_.end(), sink) == sinks_.end());
  33     sinks_.push_back(sink);
  34     AddCallback(sink, callback);
  35   }
  36
  37   void RemoveSink(MediaStreamVideoSink* sink) {
  38     DCHECK(thread_checker().CalledOnValidThread());
  39     std::vector<MediaStreamVideoSink*>::iterator it =
  40         std::find(sinks_.begin(), sinks_.end(), sink);
  41     DCHECK(it != sinks_.end());
  42     sinks_.erase(it);
  43     RemoveCallback(sink);
  44   }
  45
  46   void SetEnabled(bool enabled) {
  47     DCHECK(thread_checker().CalledOnValidThread());
  48     io_message_loop()->PostTask(
  49         FROM_HERE,
  50         base::Bind(&MediaStreamVideoTrack::FrameDeliverer::SetEnabledOnIO,
  51                    this, enabled));
  52   }
  53
  54   virtual void DeliverFrameOnIO(
  55       const scoped_refptr<media::VideoFrame>& frame,
  56       const media::VideoCaptureFormat& format) OVERRIDE {
  57     DCHECK(io_message_loop()->BelongsToCurrentThread());
  58     if (!enabled_)
  59       return;
  60     VideoFrameDeliverer::DeliverFrameOnIO(frame, format);
  61   }
  62
  63   const std::vector<MediaStreamVideoSink*>& sinks() const { return sinks_; }
  64
  65  protected:
  66   virtual ~FrameDeliverer() {
  67     DCHECK(sinks_.empty());
  68   }
  69
  70   void SetEnabledOnIO(bool enabled) {
  71     DCHECK(io_message_loop()->BelongsToCurrentThread());
  72     enabled_ = enabled;
  73   }
  74
  75  private:
  76   // The below members are used on the main render thread.
  77   std::vector<MediaStreamVideoSink*> sinks_;
  78
  79   // The below parameters are used on the IO-thread.
  80   bool enabled_;
  81
  82   DISALLOW_COPY_AND_ASSIGN(FrameDeliverer);
  83 };
  84
  85 // static
  86 blink::WebMediaStreamTrack MediaStreamVideoTrack::CreateVideoTrack(
  87     MediaStreamVideoSource* source,
  88     const blink::WebMediaConstraints& constraints,
  89     const MediaStreamVideoSource::ConstraintsCallback& callback,
  90     bool enabled) {
  91   blink::WebMediaStreamTrack track;
  92   track.initialize(source->owner());
  93   track.setExtraData(new MediaStreamVideoTrack(source,
  94                                                constraints,
  95                                                callback,
  96                                                enabled));
  97   return track;
  98 }
  99
 100 // static
 101 MediaStreamVideoTrack* MediaStreamVideoTrack::GetVideoTrack(
 102      const blink::WebMediaStreamTrack& track) {
 103   return static_cast<MediaStreamVideoTrack*>(track.extraData());
 104 }
 105
 106 MediaStreamVideoTrack::MediaStreamVideoTrack(
 107     MediaStreamVideoSource* source,
 108     const blink::WebMediaConstraints& constraints,
 109     const MediaStreamVideoSource::ConstraintsCallback& callback,
 110     bool enabled)
 111     : MediaStreamTrack(NULL, true),
 112       frame_deliverer_(
 113           new MediaStreamVideoTrack::FrameDeliverer(source->io_message_loop(),
 114                                                     enabled)),
 115       constraints_(constraints),
 116       source_(source) {
 117   source->AddTrack(this,
 118                    base::Bind(
 119                        &MediaStreamVideoTrack::FrameDeliverer::DeliverFrameOnIO,
 120                        frame_deliverer_),
 121                    constraints, callback);
 122 }
 123
 124 MediaStreamVideoTrack::~MediaStreamVideoTrack() {
 125   Stop();
 126   DVLOG(3) << "~MediaStreamVideoTrack()";
 127 }
 128
 129 void MediaStreamVideoTrack::AddSink(
 130     MediaStreamVideoSink* sink, const VideoCaptureDeliverFrameCB& callback) {
 131   DCHECK(thread_checker_.CalledOnValidThread());
 132   frame_deliverer_->AddSink(sink, callback);
 133 }
 134
 135 void MediaStreamVideoTrack::RemoveSink(MediaStreamVideoSink* sink) {
 136   DCHECK(thread_checker_.CalledOnValidThread());
 137   frame_deliverer_->RemoveSink(sink);
 138 }
 139
 140 void MediaStreamVideoTrack::SetEnabled(bool enabled) {
 141   DCHECK(thread_checker_.CalledOnValidThread());
 142   MediaStreamTrack::SetEnabled(enabled);
 143
 144   frame_deliverer_->SetEnabled(enabled);
 145   const std::vector<MediaStreamVideoSink*>& sinks = frame_deliverer_->sinks();
 146   for (std::vector<MediaStreamVideoSink*>::const_iterator it = sinks.begin();
 147        it != sinks.end(); ++it) {
 148     (*it)->OnEnabledChanged(enabled);
 149   }
 150 }
 151
 152 void MediaStreamVideoTrack::Stop() {
 153   DCHECK(thread_checker_.CalledOnValidThread());
 154   if (source_) {
 155     source_->RemoveTrack(this);
 156     source_ = NULL;
 157   }
 158   OnReadyStateChanged(blink::WebMediaStreamSource::ReadyStateEnded);
 159 }
 160
 161 void MediaStreamVideoTrack::OnReadyStateChanged(
 162     blink::WebMediaStreamSource::ReadyState state) {
 163   DCHECK(thread_checker_.CalledOnValidThread());
 164   const std::vector<MediaStreamVideoSink*>& sinks = frame_deliverer_->sinks();
 165   for (std::vector<MediaStreamVideoSink*>::const_iterator it = sinks.begin();
 166        it != sinks.end(); ++it) {
 167     (*it)->OnReadyStateChanged(state);
 168   }
 169 }
 170
 171 }  // namespace content