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/public/platform/WebAudioDevice.h"
13#include "third_party/WebKit/public/platform/WebVector.h"
14
15namespace media {
16class AudioOutputDevice;
17}
18
19namespace content {
20
21class RendererWebAudioDeviceImpl
22    : public blink::WebAudioDevice,
23      public media::AudioRendererSink::RenderCallback {
24 public:
25  RendererWebAudioDeviceImpl(const media::AudioParameters& params,
26                             blink::WebAudioDevice::RenderCallback* callback,
27                             int session_id);
28  virtual ~RendererWebAudioDeviceImpl();
29
30  // blink::WebAudioDevice implementation.
31  virtual void start();
32  virtual void stop();
33  virtual double sampleRate();
34
35  // AudioRendererSink::RenderCallback implementation.
36  virtual int Render(media::AudioBus* dest,
37                     int audio_delay_milliseconds) OVERRIDE;
38
39  virtual void OnRenderError() OVERRIDE;
40
41 private:
42  const media::AudioParameters params_;
43
44  // Weak reference to the callback into WebKit code.
45  blink::WebAudioDevice::RenderCallback* const client_callback_;
46
47  // To avoid the need for locking, ensure the control methods of the
48  // blink::WebAudioDevice implementation are called on the same thread.
49  base::ThreadChecker thread_checker_;
50
51  // When non-NULL, we are started.  When NULL, we are stopped.
52  scoped_refptr<media::AudioOutputDevice> output_device_;
53
54  // ID to allow browser to select the correct input device for unified IO.
55  int session_id_;
56
57  DISALLOW_COPY_AND_ASSIGN(RendererWebAudioDeviceImpl);
58};
59
60}  // namespace content
61
62#endif  // CONTENT_RENDERER_MEDIA_MEDIA_RENDERER_WEBAUDIODEVICE_IMPL_H_
63