media/audio/clockless_audio_sink.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 MEDIA_AUDIO_CLOCKLESS_AUDIO_SINK_H_
   6 #define MEDIA_AUDIO_CLOCKLESS_AUDIO_SINK_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/time/time.h"
  10 #include "media/base/audio_renderer_sink.h"
  11
  12 namespace base {
  13 class MessageLoopProxy;
  14 }
  15
  16 namespace media {
  17 class AudioBus;
  18 class ClocklessAudioSinkThread;
  19
  20 // Implementation of an AudioRendererSink that consumes the audio as fast as
  21 // possible. This class does not support multiple Play()/Pause() events.
  22 class MEDIA_EXPORT ClocklessAudioSink
  23     : NON_EXPORTED_BASE(public AudioRendererSink) {
  24  public:
  25   ClocklessAudioSink();
  26
  27   // AudioRendererSink implementation.
  28   virtual void Initialize(const AudioParameters& params,
  29                           RenderCallback* callback) OVERRIDE;
  30   virtual void Start() OVERRIDE;
  31   virtual void Stop() OVERRIDE;
  32   virtual void Pause() OVERRIDE;
  33   virtual void Play() OVERRIDE;
  34   virtual bool SetVolume(double volume) OVERRIDE;
  35
  36   // Returns the time taken to consume all the audio.
  37   base::TimeDelta render_time() { return playback_time_; }
  38
  39  protected:
  40   virtual ~ClocklessAudioSink();
  41
  42  private:
  43   scoped_ptr<ClocklessAudioSinkThread> thread_;
  44   bool initialized_;
  45   bool playing_;
  46
  47   // Time taken in last set of Render() calls.
  48   base::TimeDelta playback_time_;
  49
  50   DISALLOW_COPY_AND_ASSIGN(ClocklessAudioSink);
  51 };
  52
  53 }  // namespace media
  54
  55 #endif  // MEDIA_AUDIO_CLOCKLESS_AUDIO_SINK_H_