blob: 77204b2215ca6916b7b3784b53d3364150ba6aa4 [file] [log] [blame]
// Copyright 2013 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.
#ifndef MEDIA_BLINK_WEBAUDIOSOURCEPROVIDER_IMPL_H_
#define MEDIA_BLINK_WEBAUDIOSOURCEPROVIDER_IMPL_H_
#include "base/callback.h"
#include "base/memory/weak_ptr.h"
#include "base/synchronization/lock.h"
#include "media/base/audio_renderer_sink.h"
#include "media/base/media_export.h"
#include "third_party/WebKit/public/platform/WebAudioSourceProvider.h"
#include "third_party/WebKit/public/platform/WebVector.h"
namespace blink {
class WebAudioSourceProviderClient;
}
namespace media {
// WebAudioSourceProviderImpl provides a bridge between classes:
// blink::WebAudioSourceProvider <---> AudioRendererSink
//
// WebAudioSourceProviderImpl wraps an existing audio sink that is used unless
// WebKit has set a client via setClient(). While a client is set WebKit will
// periodically call provideInput() to render a certain number of audio
// sample-frames using the sink's RenderCallback to get the data.
//
// All calls are protected by a lock.
class MEDIA_EXPORT WebAudioSourceProviderImpl
: NON_EXPORTED_BASE(public blink::WebAudioSourceProvider),
NON_EXPORTED_BASE(public AudioRendererSink) {
public:
explicit WebAudioSourceProviderImpl(
const scoped_refptr<AudioRendererSink>& sink);
// blink::WebAudioSourceProvider implementation.
virtual void setClient(blink::WebAudioSourceProviderClient* client);
virtual void provideInput(const blink::WebVector<float*>& audio_data,
size_t number_of_frames);
// AudioRendererSink implementation.
void Start() override;
void Stop() override;
void Play() override;
void Pause() override;
bool SetVolume(double volume) override;
void Initialize(const AudioParameters& params,
RenderCallback* renderer) override;
protected:
virtual ~WebAudioSourceProviderImpl();
private:
// Calls setFormat() on |client_| from the Blink renderer thread.
void OnSetFormat();
// Closure that posts a task to call OnSetFormat() on the renderer thread.
base::Closure set_format_cb_;
// Set to true when Initialize() is called.
int channels_;
int sample_rate_;
double volume_;
// Tracks the current playback state.
enum PlaybackState { kStopped, kStarted, kPlaying };
PlaybackState state_;
// Where audio comes from.
AudioRendererSink::RenderCallback* renderer_;
// When set via setClient() it overrides |sink_| for consuming audio.
blink::WebAudioSourceProviderClient* client_;
// Where audio ends up unless overridden by |client_|.
base::Lock sink_lock_;
scoped_refptr<AudioRendererSink> sink_;
scoped_ptr<AudioBus> bus_wrapper_;
// NOTE: Weak pointers must be invalidated before all other member variables.
base::WeakPtrFactory<WebAudioSourceProviderImpl> weak_factory_;
DISALLOW_IMPLICIT_CONSTRUCTORS(WebAudioSourceProviderImpl);
};
} // namespace media
#endif // MEDIA_BLINK_WEBAUDIOSOURCEPROVIDER_IMPL_H_