content/renderer/media/video_frame_provider.h

// Copyright 2013 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_VIDEO_FRAME_PROVIDER_H_
#define CONTENT_RENDERER_MEDIA_VIDEO_FRAME_PROVIDER_H_

#include "base/callback.h"
#include "base/memory/ref_counted.h"
#include "content/common/content_export.h"

namespace media {
class VideoFrame;
}

namespace content {

// Define an interface to provide a sequence of video frames to clients.
// TODO(wjia): remove ref count.
// TODO(wjia): rename interface so it doesn't clash with cc::VideoFrameProvider.
class CONTENT_EXPORT VideoFrameProvider
    : public base::RefCountedThreadSafe<VideoFrameProvider> {
 public:
  typedef base::Callback<void(const scoped_refptr<media::VideoFrame>&)>
      RepaintCB;

  // Start to provide video frames to the caller.
  virtual void Start() = 0;

  // Stop to provide video frames to the caller.
  virtual void Stop() = 0;

  // Resume to provide video frames to the caller after being paused.
  virtual void Play() = 0;

  // Put the provider in pause state and the caller will not receive video
  // frames, but the provider might still generate video frames which are
  // thrown away.
  virtual void Pause() = 0;

 protected:
  friend class base::RefCountedThreadSafe<VideoFrameProvider>;

  VideoFrameProvider();
  virtual ~VideoFrameProvider();

 private:
  DISALLOW_COPY_AND_ASSIGN(VideoFrameProvider);
};

}  // namespace content

#endif  // CONTENT_RENDERER_MEDIA_VIDEO_FRAME_PROVIDER_H_