WaveShaperProcessor.cpp   [plain text]

/*
 * Copyright (C) 2011, Google Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
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 *
 * 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
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#include "config.h"

#if ENABLE(WEB_AUDIO)

#include "WaveShaperProcessor.h"

#include "WaveShaperDSPKernel.h"

namespace WebCore {
    
WaveShaperProcessor::WaveShaperProcessor(float sampleRate, size_t numberOfChannels)
    : AudioDSPKernelProcessor(sampleRate, numberOfChannels)
{
}

WaveShaperProcessor::~WaveShaperProcessor()
{
    if (isInitialized())
        uninitialize();
}

PassOwnPtr<AudioDSPKernel> WaveShaperProcessor::createKernel()
{
    return adoptPtr(new WaveShaperDSPKernel(this));
}

void WaveShaperProcessor::setCurve(Float32Array* curve)
{
    // This synchronizes with process().
    MutexLocker processLocker(m_processLock);
    
    m_curve = curve;
}

void WaveShaperProcessor::process(const AudioBus* source, AudioBus* destination, size_t framesToProcess)
{
    if (!isInitialized()) {
        destination->zero();
        return;
    }

    // The audio thread can't block on this lock, so we call tryLock() instead.
    MutexTryLocker tryLocker(m_processLock);
    if (tryLocker.locked()) {        
        // For each channel of our input, process using the corresponding WaveShaperDSPKernel into the output channel.
        for (unsigned i = 0; i < m_kernels.size(); ++i)
            m_kernels[i]->process(source->channel(i)->data(), destination->channel(i)->mutableData(), framesToProcess);
    } else {
        // Too bad - the tryLock() failed. We must be in the middle of a setCurve() call.
        destination->zero();
    }
}

} // namespace WebCore

#endif // ENABLE(WEB_AUDIO)