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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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. 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 INC. 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 AudioDestinationNode_h
#define AudioDestinationNode_h
#include "modules/webaudio/AudioBuffer.h"
#include "modules/webaudio/AudioNode.h"
#include "platform/audio/AudioBus.h"
#include "platform/audio/AudioIOCallback.h"
#include "platform/audio/AudioSourceProvider.h"
namespace blink {
class AudioBus;
class AbstractAudioContext;
class AudioDestinationHandler : public AudioHandler, public AudioIOCallback {
public:
AudioDestinationHandler(AudioNode&, float sampleRate);
~AudioDestinationHandler() override;
// AudioHandler
void process(size_t) final { } // we're pulled by hardware so this is never called
// The audio hardware calls render() to get the next render quantum of audio into destinationBus.
// It will optionally give us local/live audio input in sourceBus (if it's not 0).
void render(AudioBus* sourceBus, AudioBus* destinationBus, size_t numberOfFrames) final;
size_t currentSampleFrame() const { return acquireLoad(&m_currentSampleFrame); }
double currentTime() const { return currentSampleFrame() / static_cast<double>(sampleRate()); }
virtual unsigned long maxChannelCount() const { return 0; }
virtual void startRendering() = 0;
virtual void stopRendering() = 0;
protected:
// LocalAudioInputProvider allows us to expose an AudioSourceProvider for local/live audio input.
// If there is local/live audio input, we call set() with the audio input data every render quantum.
class LocalAudioInputProvider final : public AudioSourceProvider {
public:
LocalAudioInputProvider()
: m_sourceBus(AudioBus::create(2, ProcessingSizeInFrames)) // FIXME: handle non-stereo local input.
{
}
void set(AudioBus* bus)
{
if (bus)
m_sourceBus->copyFrom(*bus);
}
// AudioSourceProvider.
void provideInput(AudioBus* destinationBus, size_t numberOfFrames) override
{
bool isGood = destinationBus && destinationBus->length() == numberOfFrames && m_sourceBus->length() == numberOfFrames;
ASSERT(isGood);
if (isGood)
destinationBus->copyFrom(*m_sourceBus);
}
private:
RefPtr<AudioBus> m_sourceBus;
};
// Counts the number of sample-frames processed by the destination.
size_t m_currentSampleFrame;
LocalAudioInputProvider m_localAudioInputProvider;
};
class AudioDestinationNode : public AudioNode {
DEFINE_WRAPPERTYPEINFO();
public:
AudioDestinationHandler& audioDestinationHandler() const;
unsigned long maxChannelCount() const;
protected:
AudioDestinationNode(AbstractAudioContext&);
};
} // namespace blink
#endif // AudioDestinationNode_h
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