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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef AudioDestination_h
#define AudioDestination_h
#include "platform/audio/AudioBus.h"
#include "platform/audio/AudioIOCallback.h"
#include "platform/audio/AudioSourceProvider.h"
#include "public/platform/WebAudioDevice.h"
#include "public/platform/WebVector.h"
#include "wtf/Allocator.h"
#include "wtf/Noncopyable.h"
#include "wtf/text/WTFString.h"
#include <memory>
namespace blink {
class AudioPullFIFO;
class SecurityOrigin;
// The AudioDestination class is an audio sink interface between the media
// renderer and the Blink's WebAudio module. It has a FIFO to adapt the
// different processing block sizes of WebAudio renderer and actual hardware
// audio callback.
class PLATFORM_EXPORT AudioDestination : public WebAudioDevice::RenderCallback,
public AudioSourceProvider {
USING_FAST_MALLOC(AudioDestination);
WTF_MAKE_NONCOPYABLE(AudioDestination);
public:
AudioDestination(AudioIOCallback&,
unsigned numberOfOutputChannels,
float sampleRate,
PassRefPtr<SecurityOrigin>);
~AudioDestination() override;
static std::unique_ptr<AudioDestination> create(
AudioIOCallback&,
unsigned numberOfOutputChannels,
float sampleRate,
PassRefPtr<SecurityOrigin>);
// The actual render function (WebAudioDevice::RenderCallback) isochronously
// invoked by the media renderer.
void render(const WebVector<float*>& destinationData,
size_t numberOfFrames,
double delay,
double delayTimestamp,
size_t priorFramesSkipped) override;
// AudioSourceProvider (FIFO)
void provideInput(AudioBus* outputBus, size_t framesToProcess) override;
virtual void start();
virtual void stop();
size_t callbackBufferSize() const { return m_callbackBufferSize; }
float sampleRate() const { return m_sampleRate; }
bool isPlaying() { return m_isPlaying; }
// The information from the actual audio hardware. (via Platform::current)
static float hardwareSampleRate();
static unsigned long maxChannelCount();
private:
std::unique_ptr<WebAudioDevice> m_webAudioDevice;
unsigned m_numberOfOutputChannels;
size_t m_callbackBufferSize;
float m_sampleRate;
bool m_isPlaying;
// The render callback function of WebAudio engine. (i.e. DestinationNode)
AudioIOCallback& m_callback;
RefPtr<AudioBus> m_outputBus;
std::unique_ptr<AudioPullFIFO> m_fifo;
size_t m_framesElapsed;
AudioIOPosition m_outputPosition;
base::TimeTicks m_outputPositionReceivedTimestamp;
// Calculate the optimum buffer size for a given platform. Return false if the
// buffer size calculation fails.
bool calculateBufferSize();
size_t hardwareBufferSize();
};
} // namespace blink
#endif // AudioDestination_h
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