blob: 006a30f59ba1ccbb8b1daffc4cc04d7764fd013a [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// RenderAudioSourceProvider provides a bridge between classes:
// WebKit::WebAudioSourceProvider <---> media::AudioRendererSink
//
// RenderAudioSourceProvider is a "sink" of audio, and uses a default
// AudioOutputDevice if a client has not explicitly been set.
//
// WebKit optionally sets a client, and then periodically calls provideInput()
// to render a certain number of audio sample-frames. provideInput()
// uses the renderer to get this data, and then massages it into the form
// required by provideInput(). In this case, the default AudioOutputDevice
// is no longer used.
//
// THREAD SAFETY:
// It is assumed that the callers to setClient() and provideInput()
// implement appropriate locking for thread safety when making
// these calls. This happens in WebKit.
#ifndef CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_
#define CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_
#include <vector>
#include "base/synchronization/lock.h"
#include "media/base/audio_renderer_sink.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebVector.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebAudioSourceProvider.h"
namespace WebKit {
class WebAudioSourceProviderClient;
}
class RenderAudioSourceProvider
: public WebKit::WebAudioSourceProvider,
public media::AudioRendererSink {
public:
RenderAudioSourceProvider();
// WebKit::WebAudioSourceProvider implementation.
// WebKit calls setClient() if it desires to take control of the rendered
// audio stream. We call client's setFormat() when the audio stream format
// is known.
virtual void setClient(WebKit::WebAudioSourceProviderClient* client);
// If setClient() has been called, then WebKit calls provideInput()
// periodically to get the rendered audio stream.
virtual void provideInput(const WebKit::WebVector<float*>& audio_data,
size_t number_of_frames);
// AudioRendererSink implementation.
virtual void Start() OVERRIDE;
virtual void Stop() OVERRIDE;
virtual void Play() OVERRIDE;
virtual void Pause(bool flush) OVERRIDE;
virtual bool SetVolume(double volume) OVERRIDE;
virtual void Initialize(const media::AudioParameters& params,
RenderCallback* renderer) OVERRIDE;
protected:
virtual ~RenderAudioSourceProvider();
private:
// Set to true when Initialize() is called.
bool is_initialized_;
int channels_;
int sample_rate_;
bool is_running_;
media::AudioRendererSink::RenderCallback* renderer_;
WebKit::WebAudioSourceProviderClient* client_;
// Protects access to sink_
base::Lock sink_lock_;
// default_sink_ is the default sink.
scoped_refptr<media::AudioRendererSink> default_sink_;
DISALLOW_COPY_AND_ASSIGN(RenderAudioSourceProvider);
};
#endif // CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_