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/memory/scoped_vector.h" 13 #include "base/threading/thread_checker.h" 14 #include "content/common/content_export.h" 15 #include "content/public/renderer/media_stream_video_sink.h" 16 #include "content/renderer/media/media_stream_track.h" 17 #include "content/renderer/media/media_stream_video_source.h" 18 19 namespace content { 20 21 // MediaStreamVideoTrack is a video specific representation of a 22 // blink::WebMediaStreamTrack in content. It is owned by the blink object 23 // and can be retrieved from a blink object using 24 // WebMediaStreamTrack::extraData() or MediaStreamVideoTrack::GetVideoTrack. 25 class CONTENT_EXPORT MediaStreamVideoTrack : public MediaStreamTrack { 26 public: 27 // Help method to create a blink::WebMediaStreamTrack and a 28 // MediaStreamVideoTrack instance. The MediaStreamVideoTrack object is owned 29 // by the blink object in its WebMediaStreamTrack::ExtraData member. 30 // |callback| is triggered if the track is added to the source 31 // successfully and will receive video frames that match |constraints| 32 // or if the source fail to provide video frames. 33 // If |enabled| is true, sinks added to the track will 34 // receive video frames when the source deliver frames to the track. 35 static blink::WebMediaStreamTrack CreateVideoTrack( 36 MediaStreamVideoSource* source, 37 const blink::WebMediaConstraints& constraints, 38 const MediaStreamVideoSource::ConstraintsCallback& callback, 39 bool enabled); 40 41 static MediaStreamVideoTrack* GetVideoTrack( 42 const blink::WebMediaStreamTrack& track); 43 44 // Constructor for video tracks. 45 MediaStreamVideoTrack( 46 MediaStreamVideoSource* source, 47 const blink::WebMediaConstraints& constraints, 48 const MediaStreamVideoSource::ConstraintsCallback& callback, 49 bool enabled); 50 virtual ~MediaStreamVideoTrack(); 51 52 virtual void SetEnabled(bool enabled) OVERRIDE; 53 virtual void Stop() OVERRIDE; 54 55 void OnReadyStateChanged(blink::WebMediaStreamSource::ReadyState state); 56 constraints()57 const blink::WebMediaConstraints& constraints() const { 58 return constraints_; 59 } 60 61 protected: 62 // Used to DCHECK that we are called on the correct thread. 63 base::ThreadChecker thread_checker_; 64 65 private: 66 // MediaStreamVideoSink is a friend to allow it to call AddSink() and 67 // RemoveSink(). 68 friend class MediaStreamVideoSink; 69 FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, StartTrack); 70 FRIEND_TEST_ALL_PREFIXES(MediaStreamRemoteVideoSourceTest, RemoteTrackStop); 71 FRIEND_TEST_ALL_PREFIXES(VideoDestinationHandlerTest, PutFrame); 72 73 // Add |sink| to receive state changes on the main render thread and video 74 // frames in the |callback| method on the IO-thread. 75 // |callback| will be reset on the render thread. 76 // These two methods are private such that no subclass can intercept and 77 // store the callback. This is important to ensure that we can release 78 // the callback on render thread without reference to it on the IO-thread. 79 void AddSink(MediaStreamVideoSink* sink, 80 const VideoCaptureDeliverFrameCB& callback); 81 void RemoveSink(MediaStreamVideoSink* sink); 82 83 std::vector<MediaStreamVideoSink*> sinks_; 84 85 // |FrameDeliverer| is an internal helper object used for delivering video 86 // frames on the IO-thread using callbacks to all registered tracks. 87 class FrameDeliverer; 88 scoped_refptr<FrameDeliverer> frame_deliverer_; 89 90 blink::WebMediaConstraints constraints_; 91 92 // Weak ref to the source this tracks is connected to. |source_| is owned 93 // by the blink::WebMediaStreamSource and is guaranteed to outlive the 94 // track. 95 MediaStreamVideoSource* source_; 96 97 DISALLOW_COPY_AND_ASSIGN(MediaStreamVideoTrack); 98 }; 99 100 } // namespace content 101 102 #endif // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_ 103