content/renderer/media/media_stream_video_track.h

   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 #ifndef CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_
   6 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_
   7
   8 #include <vector>
   9
  10 #include "base/compiler_specific.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/threading/thread_checker.h"
  13 #include "content/common/content_export.h"
  14 #include "content/public/renderer/media_stream_video_sink.h"
  15 #include "content/renderer/media/media_stream_track.h"
  16 #include "content/renderer/media/media_stream_video_source.h"
  17
  18 namespace content {
  19
  20 // MediaStreamVideoTrack is a video specific representation of a
  21 // blink::WebMediaStreamTrack in content. It is owned by the blink object
  22 // and can be retrieved from a blink object using
  23 // WebMediaStreamTrack::extraData() or MediaStreamVideoTrack::GetVideoTrack.
  24 class CONTENT_EXPORT MediaStreamVideoTrack : public MediaStreamTrack {
  25  public:
  26   // Help method to create a blink::WebMediaStreamTrack and a
  27   // MediaStreamVideoTrack instance. The MediaStreamVideoTrack object is owned
  28   // by the blink object in its WebMediaStreamTrack::ExtraData member.
  29   // |callback| is triggered if the track is added to the source
  30   // successfully and will receive video frames that match |constraints|
  31   // or if the source fail to provide video frames.
  32   // If |enabled| is true, sinks added to the track will
  33   // receive video frames when the source deliver frames to the track.
  34   static blink::WebMediaStreamTrack CreateVideoTrack(
  35       MediaStreamVideoSource* source,
  36       const blink::WebMediaConstraints& constraints,
  37       const MediaStreamVideoSource::ConstraintsCallback& callback,
  38       bool enabled);
  39
  40   static MediaStreamVideoTrack* GetVideoTrack(
  41       const blink::WebMediaStreamTrack& track);
  42
  43   // Constructor for video tracks.
  44   MediaStreamVideoTrack(
  45       MediaStreamVideoSource* source,
  46       const blink::WebMediaConstraints& constraints,
  47       const MediaStreamVideoSource::ConstraintsCallback& callback,
  48       bool enabled);
  49   virtual ~MediaStreamVideoTrack();
  50
  51   void SetEnabled(bool enabled) override;
  52
  53   void Stop() override;
  54
  55   void OnReadyStateChanged(blink::WebMediaStreamSource::ReadyState state);
  56
  57   const blink::WebMediaConstraints& constraints() const { return constraints_; }
  58
  59  private:
  60   // MediaStreamVideoSink is a friend to allow it to call AddSink() and
  61   // RemoveSink().
  62   friend class MediaStreamVideoSink;
  63   FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, StartTrack);
  64   FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, RemoteTrackStop);
  65   FRIEND_TEST_ALL_PREFIXES(PepperToVideoTrackAdapterTest, PutFrame);
  66
  67   // Add |sink| to receive state changes on the main render thread and video
  68   // frames in the |callback| method on the IO-thread.
  69   // |callback| will be reset on the render thread.
  70   // These two methods are private such that no subclass can intercept and
  71   // store the callback. This is important to ensure that we can release
  72   // the callback on render thread without reference to it on the IO-thread.
  73   void AddSink(MediaStreamVideoSink* sink,
  74                const VideoCaptureDeliverFrameCB& callback);
  75   void RemoveSink(MediaStreamVideoSink* sink);
  76
  77   std::vector<MediaStreamVideoSink*> sinks_;
  78
  79   // |FrameDeliverer| is an internal helper object used for delivering video
  80   // frames on the IO-thread using callbacks to all registered tracks.
  81   class FrameDeliverer;
  82   const scoped_refptr<FrameDeliverer> frame_deliverer_;
  83
  84   const blink::WebMediaConstraints constraints_;
  85
  86   // Weak ref to the source this tracks is connected to.  |source_| is owned
  87   // by the blink::WebMediaStreamSource and is guaranteed to outlive the
  88   // track.
  89   MediaStreamVideoSource* source_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(MediaStreamVideoTrack);
  92 };
  93
  94 }  // namespace content
  95
  96 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_