webkit/media/video_frame_provider.h

   1 // Copyright (c) 2012 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 WEBKIT_MEDIA_VIDEO_FRAME_PROVIDER_H_
   6 #define WEBKIT_MEDIA_VIDEO_FRAME_PROVIDER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/ref_counted.h"
  10
  11 namespace media {
  12 class VideoFrame;
  13 }
  14
  15 namespace webkit_media {
  16
  17 // Define an interface to provide a sequence of video frames to clients.
  18 // TODO(wjia): remove ref count.
  19 class VideoFrameProvider
  20     : public base::RefCountedThreadSafe<VideoFrameProvider> {
  21  public:
  22   typedef base::Callback<void(const scoped_refptr<media::VideoFrame>&)>
  23       RepaintCB;
  24
  25   // Start to provide video frames to the caller.
  26   virtual void Start() = 0;
  27
  28   // Stop to provide video frames to the caller.
  29   virtual void Stop() = 0;
  30
  31   // Resume to provide video frames to the caller after being paused.
  32   virtual void Play() = 0;
  33
  34   // Put the provider in pause state and the caller will not receive video
  35   // frames, but the provider might still generate video frames which are
  36   // thrown away.
  37   virtual void Pause() = 0;
  38
  39  protected:
  40   friend class base::RefCountedThreadSafe<VideoFrameProvider>;
  41   VideoFrameProvider();
  42   virtual ~VideoFrameProvider();
  43
  44  private:
  45   DISALLOW_COPY_AND_ASSIGN(VideoFrameProvider);
  46 };
  47
  48 }  // namespace webkit_media
  49
  50 #endif  // WEBKIT_MEDIA_VIDEO_FRAME_PROVIDER_H_