content/renderer/media/video_frame_provider.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_VIDEO_FRAME_PROVIDER_H_
   6 #define CONTENT_RENDERER_MEDIA_VIDEO_FRAME_PROVIDER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "content/common/content_export.h"
  11
  12 namespace media {
  13 class VideoFrame;
  14 }
  15
  16 namespace content {
  17
  18 // Define an interface to provide a sequence of video frames to clients.
  19 // TODO(wjia): remove ref count.
  20 // TODO(wjia): rename interface so it doesn't clash with cc::VideoFrameProvider.
  21 class CONTENT_EXPORT VideoFrameProvider
  22     : public base::RefCountedThreadSafe<VideoFrameProvider> {
  23  public:
  24   typedef base::Callback<void(const scoped_refptr<media::VideoFrame>&)>
  25       RepaintCB;
  26
  27   // Start to provide video frames to the caller.
  28   virtual void Start() = 0;
  29
  30   // Stop to provide video frames to the caller.
  31   virtual void Stop() = 0;
  32
  33   // Resume to provide video frames to the caller after being paused.
  34   virtual void Play() = 0;
  35
  36   // Put the provider in pause state and the caller will not receive video
  37   // frames, but the provider might still generate video frames which are
  38   // thrown away.
  39   virtual void Pause() = 0;
  40
  41  protected:
  42   friend class base::RefCountedThreadSafe<VideoFrameProvider>;
  43
  44   VideoFrameProvider();
  45   virtual ~VideoFrameProvider();
  46
  47  private:
  48   DISALLOW_COPY_AND_ASSIGN(VideoFrameProvider);
  49 };
  50
  51 }  // namespace content
  52
  53 #endif  // CONTENT_RENDERER_MEDIA_VIDEO_FRAME_PROVIDER_H_