| // Copyright (c) 2012 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 MEDIA_BASE_VIDEO_RENDERER_H_ |
| #define MEDIA_BASE_VIDEO_RENDERER_H_ |
| |
| #include "base/callback.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/time/time.h" |
| #include "media/base/buffering_state.h" |
| #include "media/base/media_export.h" |
| #include "media/base/pipeline_status.h" |
| |
| namespace media { |
| |
| class DemuxerStream; |
| class VideoDecoder; |
| |
| class MEDIA_EXPORT VideoRenderer { |
| public: |
| // Used to query the current time or duration of the media. |
| typedef base::Callback<base::TimeDelta()> TimeDeltaCB; |
| |
| VideoRenderer(); |
| |
| // Stops all operations and fires all pending callbacks. |
| virtual ~VideoRenderer(); |
| |
| // Initializes a VideoRenderer with |stream|, executing |init_cb| upon |
| // completion. |
| // |
| // |statistics_cb| is executed periodically with video rendering stats, such |
| // as dropped frames. |
| // |
| // |buffering_state_cb| is executed when video rendering has either run out of |
| // data or has enough data to continue playback. |
| // |
| // |ended_cb| is executed when video rendering has reached the end of stream. |
| // |
| // |error_cb| is executed if an error was encountered. |
| // |
| // |get_time_cb| is used to query the current media playback time. |
| virtual void Initialize(DemuxerStream* stream, |
| bool low_delay, |
| const PipelineStatusCB& init_cb, |
| const StatisticsCB& statistics_cb, |
| const BufferingStateCB& buffering_state_cb, |
| const base::Closure& ended_cb, |
| const PipelineStatusCB& error_cb, |
| const TimeDeltaCB& get_time_cb) = 0; |
| |
| // Discards any video data and stops reading from |stream|, executing |
| // |callback| when completed. |
| // |
| // Clients should expect |buffering_state_cb| to be called with |
| // BUFFERING_HAVE_NOTHING while flushing is in progress. |
| virtual void Flush(const base::Closure& callback) = 0; |
| |
| // Starts playback at |timestamp| by reading from |stream| and decoding and |
| // rendering video. |
| // |
| // Only valid to call after a successful Initialize() or Flush(). |
| virtual void StartPlayingFrom(base::TimeDelta timestamp) = 0; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(VideoRenderer); |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_BASE_VIDEO_RENDERER_H_ |