Implement a source for remote video tracks.

content/renderer/media/webrtc/media_stream_remote_video_source.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_RENDERER_MEDIA_WEBRTC_MEDIA_STREAM_REMOTE_VIDEO_SOURCE_H_
+#define CONTENT_RENDERER_MEDIA_WEBRTC_MEDIA_STREAM_REMOTE_VIDEO_SOURCE_H_
+
+#include "base/memory/weak_ptr.h"
+#include "content/common/content_export.h"
+#include "content/renderer/media/media_stream_video_source.h"
+#include "media/base/video_frame_pool.h"
+#include "third_party/WebKit/public/platform/WebMediaStreamSource.h"
+#include "third_party/libjingle/source/talk/app/webrtc/mediastreaminterface.h"

[Ronghua Wu (Left Chromium), 2014/03/17 22:45:35]

move one line above

[perkj_chrome, 2014/03/19 16:34:48]

actually - WebKit includes must come first in third_party includes. Otherwise
the presubmit script complains.

+
+namespace content {
+
+// MediaStreamRemoteVideoSource implements the MediaStreamVideoSource interface
+// for video tracks received on a PeerConnection. The purpose of the class is
+// to make sure there is no difference between a video track where the source is
+// a local source and a video track where the source is a remote video track.
+class CONTENT_EXPORT MediaStreamRemoteVideoSource
+     : public MediaStreamVideoSource,
+       public webrtc::VideoRendererInterface,
+       public webrtc::ObserverInterface,
+       public base::SupportsWeakPtr<MediaStreamRemoteVideoSource> {
+ public:
+  explicit MediaStreamRemoteVideoSource(
+      webrtc::VideoTrackInterface* remote_track);
+  virtual ~MediaStreamRemoteVideoSource();
+
+ protected:
+  // Implements MediaStreamVideoSource.
+  virtual void GetCurrentSupportedFormats(
+      int max_requested_width,
+      int max_requested_height) OVERRIDE;
+
+  virtual void StartSourceImpl(
+      const media::VideoCaptureParams& params) OVERRIDE;
+
+  virtual void StopSourceImpl() OVERRIDE;
+
+  virtual webrtc::VideoSourceInterface* GetAdapter() OVERRIDE;
+
+  // Implements webrtc::VideoRendererInterface used for receiving video frames
+  // from the PeerConnection video track. May be called on
+  // a different thread.
+  virtual void SetSize(int width, int height) OVERRIDE;
+  virtual void RenderFrame(const cricket::VideoFrame* frame) OVERRIDE;
+
+  // webrtc::ObserverInterface implementation.
+  virtual void OnChanged() OVERRIDE;
+
+ private:
+  void FrameFormatOnMainThread(const media::VideoCaptureFormat& format);
+  void DoRenderFrameOnMainThread(scoped_refptr<media::VideoFrame> video_frame);
+
+  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  scoped_refptr<webrtc::VideoTrackInterface> remote_track_;
+  webrtc::MediaStreamTrackInterface::TrackState track_state_;
+
+  // |first_frame_received_| and |frame_pool_| are only accessed on whatever
+  /// thread webrtc::VideoRendererInterface::RenderFrame is called on.

[Ronghua Wu (Left Chromium), 2014/03/17 22:45:35]

remove extra /

[perkj_chrome, 2014/03/19 16:34:48]

Done.

+  bool first_frame_received_;
+  media::VideoFramePool frame_pool_;
+
+  // |format_| is the format currently received by this source.
+  media::VideoCaptureFormat format_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaStreamRemoteVideoSource);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MEDIA_WEBRTC_MEDIA_STREAM_REMOTE_VIDEO_SOURCE_H_