content/renderer/media/renderer_webaudiodevice_impl.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 CONTENT_RENDERER_MEDIA_MEDIA_RENDERER_WEBAUDIODEVICE_IMPL_H_
   6 #define CONTENT_RENDERER_MEDIA_MEDIA_RENDERER_WEBAUDIODEVICE_IMPL_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "base/threading/thread_checker.h"
  10 #include "media/audio/audio_parameters.h"
  11 #include "media/base/audio_renderer_sink.h"
  12 #include "third_party/WebKit/Source/Platform/chromium/public/WebAudioDevice.h"
  13 #include "third_party/WebKit/Source/Platform/chromium/public/WebVector.h"
  14
  15 namespace content {
  16
  17 class RendererAudioOutputDevice;
  18
  19 class RendererWebAudioDeviceImpl
  20     : public WebKit::WebAudioDevice,
  21       public media::AudioRendererSink::RenderCallback {
  22  public:
  23   RendererWebAudioDeviceImpl(const media::AudioParameters& params,
  24                              WebKit::WebAudioDevice::RenderCallback* callback);
  25   virtual ~RendererWebAudioDeviceImpl();
  26
  27   // WebKit::WebAudioDevice implementation.
  28   virtual void start();
  29   virtual void stop();
  30   virtual double sampleRate();
  31
  32   // AudioRendererSink::RenderCallback implementation.
  33   virtual int Render(media::AudioBus* dest,
  34                      int audio_delay_milliseconds) OVERRIDE;
  35
  36   virtual void RenderIO(media::AudioBus* source,
  37                         media::AudioBus* dest,
  38                         int audio_delay_milliseconds) OVERRIDE;
  39
  40   virtual void OnRenderError() OVERRIDE;
  41
  42  private:
  43   const media::AudioParameters params_;
  44
  45   // Weak reference to the callback into WebKit code.
  46   WebKit::WebAudioDevice::RenderCallback* const client_callback_;
  47
  48   // To avoid the need for locking, ensure the control methods of the
  49   // WebKit::WebAudioDevice implementation are called on the same thread.
  50   base::ThreadChecker thread_checker_;
  51
  52   // When non-NULL, we are started.  When NULL, we are stopped.
  53   scoped_refptr<RendererAudioOutputDevice> output_device_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(RendererWebAudioDeviceImpl);
  56 };
  57
  58 }  // namespace content
  59
  60 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_RENDERER_WEBAUDIODEVICE_IMPL_H_