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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.
*/
#include "config.h"
#if ENABLE(WEB_AUDIO)
#include "AudioBasicProcessorNode.h"
#include "AudioBus.h"
#include "AudioContext.h"
#include "AudioNodeInput.h"
#include "AudioNodeOutput.h"
#include "AudioProcessor.h"
namespace WebCore {
AudioBasicProcessorNode::AudioBasicProcessorNode(AudioContext* context, double sampleRate)
: AudioNode(context, sampleRate)
{
addInput(adoptPtr(new AudioNodeInput(this)));
addOutput(adoptPtr(new AudioNodeOutput(this, 0)));
// The subclass must create m_processor.
}
void AudioBasicProcessorNode::initialize()
{
if (isInitialized())
return;
ASSERT(processor());
processor()->initialize();
AudioNode::initialize();
}
void AudioBasicProcessorNode::uninitialize()
{
if (!isInitialized())
return;
ASSERT(processor());
processor()->uninitialize();
AudioNode::uninitialize();
}
void AudioBasicProcessorNode::process(size_t framesToProcess)
{
AudioBus* destinationBus = output(0)->bus();
// The realtime thread can't block on this lock, so we call tryLock() instead.
if (m_processLock.tryLock()) {
if (!isInitialized() || !processor())
destinationBus->zero();
else {
AudioBus* sourceBus = input(0)->bus();
// FIXME: if we take "tail time" into account, then we can avoid calling processor()->process() once the tail dies down.
if (!input(0)->isConnected())
sourceBus->zero();
processor()->process(sourceBus, destinationBus, framesToProcess);
}
m_processLock.unlock();
} else {
// Too bad - the tryLock() failed. We must be in the middle of re-connecting and were already outputting silence anyway...
destinationBus->zero();
}
}
// Nice optimization in the very common case allowing for "in-place" processing
void AudioBasicProcessorNode::pullInputs(size_t framesToProcess)
{
// Render input stream - suggest to the input to render directly into output bus for in-place processing in process() if possible.
input(0)->pull(output(0)->bus(), framesToProcess);
}
void AudioBasicProcessorNode::reset()
{
if (processor())
processor()->reset();
}
// As soon as we know the channel count of our input, we can lazily initialize.
// Sometimes this may be called more than once with different channel counts, in which case we must safely
// uninitialize and then re-initialize with the new channel count.
void AudioBasicProcessorNode::checkNumberOfChannelsForInput(AudioNodeInput* input)
{
ASSERT(context()->isAudioThread() && context()->isGraphOwner());
ASSERT(input == this->input(0));
if (input != this->input(0))
return;
ASSERT(processor());
if (!processor())
return;
unsigned numberOfChannels = input->numberOfChannels();
if (isInitialized() && numberOfChannels != output(0)->numberOfChannels()) {
// We're already initialized but the channel count has changed.
// We need to be careful since we may be actively processing right now, so synchronize with process().
MutexLocker locker(m_processLock);
uninitialize();
}
if (!isInitialized()) {
// This will propagate the channel count to any nodes connected further down the chain...
output(0)->setNumberOfChannels(numberOfChannels);
// Re-initialize the processor with the new channel count.
processor()->setNumberOfChannels(numberOfChannels);
initialize();
}
}
unsigned AudioBasicProcessorNode::numberOfChannels()
{
return output(0)->numberOfChannels();
}
} // namespace WebCore
#endif // ENABLE(WEB_AUDIO)
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