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 <string>
   9
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/time/time.h"
  12 #include "media/base/audio_renderer_sink.h"
  13
  14 namespace base {
  15 class SingleThreadTaskRunner;
  16 }
  17
  18 namespace media {
  19 class AudioBus;
  20 class ClocklessAudioSinkThread;
  21
  22 // Implementation of an AudioRendererSink that consumes the audio as fast as
  23 // possible. This class does not support multiple Play()/Pause() events.
  24 class MEDIA_EXPORT ClocklessAudioSink
  25     : NON_EXPORTED_BASE(public AudioRendererSink) {
  26  public:
  27   ClocklessAudioSink();
  28
  29   // AudioRendererSink implementation.
  30   void Initialize(const AudioParameters& params,
  31                   RenderCallback* callback) override;
  32   void Start() override;
  33   void Stop() override;
  34   void Pause() override;
  35   void Play() override;
  36   bool SetVolume(double volume) override;
  37   void SwitchOutputDevice(const std::string& device_id,
  38                           const GURL& security_origin,
  39                           const SwitchOutputDeviceCB& callback) override;
  40
  41   // Returns the time taken to consume all the audio.
  42   base::TimeDelta render_time() { return playback_time_; }
  43
  44  protected:
  45   ~ClocklessAudioSink() override;
  46
  47  private:
  48   scoped_ptr<ClocklessAudioSinkThread> thread_;
  49   bool initialized_;
  50   bool playing_;
  51
  52   // Time taken in last set of Render() calls.
  53   base::TimeDelta playback_time_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(ClocklessAudioSink);
  56 };
  57
  58 }  // namespace media
  59
  60 #endif  // MEDIA_AUDIO_CLOCKLESS_AUDIO_SINK_H_