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 MessageLoopProxy;
  15 }
  16
  17 namespace media {
  18 class AudioBus;
  19 class AudioHash;
  20 class FakeAudioConsumer;
  21
  22 class MEDIA_EXPORT NullAudioSink
  23     : NON_EXPORTED_BASE(public AudioRendererSink) {
  24  public:
  25   NullAudioSink(const scoped_refptr<base::MessageLoopProxy>& message_loop);
  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   // Enables audio frame hashing.  Must be called prior to Initialize().
  37   void StartAudioHashForTesting();
  38
  39   // Returns the hash of all audio frames seen since construction.
  40   std::string GetAudioHashForTesting();
  41
  42  protected:
  43   virtual ~NullAudioSink();
  44
  45  private:
  46   // Task that periodically calls Render() to consume audio data.
  47   void CallRender(AudioBus* audio_bus);
  48
  49   bool initialized_;
  50   bool playing_;
  51   RenderCallback* callback_;
  52
  53   // Controls whether or not a running hash is computed for audio frames.
  54   scoped_ptr<AudioHash> audio_hash_;
  55
  56   scoped_refptr<base::MessageLoopProxy> message_loop_;
  57   scoped_ptr<FakeAudioConsumer> fake_consumer_;
  58
  59   DISALLOW_COPY_AND_ASSIGN(NullAudioSink);
  60 };
  61
  62 }  // namespace media
  63
  64 #endif  // MEDIA_AUDIO_NULL_AUDIO_SINK_H_