| // 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 MEDIA_FILTERS_VIDEO_FRAME_SCHEDULER_H_ |
| #define MEDIA_FILTERS_VIDEO_FRAME_SCHEDULER_H_ |
| |
| #include "base/callback.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/time/time.h" |
| #include "media/base/media_export.h" |
| |
| namespace media { |
| |
| class VideoFrame; |
| |
| // Defines an abstract video frame scheduler that is capable of managing the |
| // display of video frames at explicit times. |
| class MEDIA_EXPORT VideoFrameScheduler { |
| public: |
| VideoFrameScheduler() {} |
| virtual ~VideoFrameScheduler() {} |
| |
| enum Reason { |
| DISPLAYED, // Frame was displayed. |
| DROPPED, // Frame was dropped. |
| }; |
| typedef base::Callback<void(const scoped_refptr<VideoFrame>&, Reason)> DoneCB; |
| |
| // Schedule |frame| to be displayed at |wall_ticks|, firing |done_cb| when |
| // the scheduler has finished with the frame. |
| // |
| // To avoid reentrancy issues, |done_cb| is run on a separate calling stack. |
| virtual void ScheduleVideoFrame(const scoped_refptr<VideoFrame>& frame, |
| base::TimeTicks wall_ticks, |
| const DoneCB& done_cb) = 0; |
| |
| // Causes the scheduler to cancel any previously scheduled frames. |
| // |
| // There is no guarantee that |done_cb|'s for previously scheduled frames |
| // will not be run. Clients should implement callback tracking/cancellation |
| // if they are sensitive to old callbacks being run. |
| virtual void Reset() = 0; |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_FILTERS_VIDEO_FRAME_SCHEDULER_H_ |