media/audio/null_audio_sink.h

   1 // Copyright (c) 2012 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_NULL_AUDIO_SINK_H_
   6 #define MEDIA_AUDIO_NULL_AUDIO_SINK_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/scoped_ptr.h"
  11 #include "media/base/audio_renderer_sink.h"
  12
  13 namespace base {
  14 class SingleThreadTaskRunner;
  15 }
  16
  17 namespace media {
  18 class AudioBus;
  19 class AudioHash;
  20 class FakeAudioWorker;
  21
  22 class MEDIA_EXPORT NullAudioSink
  23     : NON_EXPORTED_BASE(public AudioRendererSink) {
  24  public:
  25   NullAudioSink(const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
  26
  27   // AudioRendererSink implementation.
  28   void Initialize(const AudioParameters& params,
  29                   RenderCallback* callback) override;
  30   void Start() override;
  31   void Stop() override;
  32   void Pause() override;
  33   void Play() override;
  34   bool SetVolume(double volume) override;
  35   void SwitchOutputDevice(const std::string& device_id,
  36                           const GURL& security_origin,
  37                           const SwitchOutputDeviceCB& callback) override;
  38
  39   // Enables audio frame hashing.  Must be called prior to Initialize().
  40   void StartAudioHashForTesting();
  41
  42   // Returns the hash of all audio frames seen since construction.
  43   std::string GetAudioHashForTesting();
  44
  45  protected:
  46   ~NullAudioSink() override;
  47
  48  private:
  49   // Task that periodically calls Render() to consume audio data.
  50   void CallRender();
  51
  52   bool initialized_;
  53   bool playing_;
  54   RenderCallback* callback_;
  55
  56   // Controls whether or not a running hash is computed for audio frames.
  57   scoped_ptr<AudioHash> audio_hash_;
  58
  59   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  60   scoped_ptr<FakeAudioWorker> fake_worker_;
  61   scoped_ptr<AudioBus> audio_bus_;
  62
  63   DISALLOW_COPY_AND_ASSIGN(NullAudioSink);
  64 };
  65
  66 }  // namespace media
  67
  68 #endif  // MEDIA_AUDIO_NULL_AUDIO_SINK_H_