2010-10-04  Chris Rogers  <crogers@google.com>

        Reviewed by NOBODY (OOPS!).

        Add BiquadProcessor files

        https://bugs.webkit.org/show_bug.cgi?id=46527

        No new tests since audio API is not yet implemented.

        * webaudio/BiquadProcessor.cpp: Added.

        (WebCore::BiquadProcessor::BiquadProcessor):

        (WebCore::BiquadProcessor::~BiquadProcessor):

        (WebCore::BiquadProcessor::createKernel):

        (WebCore::BiquadProcessor::process):

        * webaudio/BiquadProcessor.h: Added.

        (WebCore::BiquadProcessor::filterCoefficientsDirty):

        (WebCore::BiquadProcessor::parameter1):

        (WebCore::BiquadProcessor::parameter2):

        (WebCore::BiquadProcessor::parameter3):

        (WebCore::BiquadProcessor::type):

/*

 * 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 "BiquadProcessor.h"

#include "BiquadDSPKernel.h"

namespace WebCore {

BiquadProcessor::BiquadProcessor(FilterType type, double sampleRate, size_t numberOfChannels, bool autoInitialize)

    : AudioDSPKernelProcessor(sampleRate, numberOfChannels)

    , m_type(type)

    , m_parameter1(0)

    , m_parameter2(0)

    , m_parameter3(0)

    , m_filterCoefficientsDirty(true)

{

    double nyquist = 0.5 * this->sampleRate();

    switch (type) {

    case LowPass2:

        m_parameter1 = AudioParam::create("frequency", 350.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("resonance", 0.0, -20.0, 20.0);

        m_parameter3 = AudioParam::create("unused", 0.0, 0.0, 1.0);

        break;

    case HighPass2:

        m_parameter1 = AudioParam::create("frequency", 350.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("resonance", 0.0, -20.0, 20.0);

        m_parameter3 = AudioParam::create("unused", 0.0, 0.0, 1.0);

        break;

    case Peaking:

        m_parameter1 = AudioParam::create("frequency", 2500.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("gain", 0.0, -20.0, 20.0);

        m_parameter3 = AudioParam::create("Q", 0.5, 0.0, 1000.0);

        break;

    case Allpass:

        m_parameter1 = AudioParam::create("frequency", 2500.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("Q", 0.5, 0.0, 1000.0);

        m_parameter3 = AudioParam::create("unused", 0.0, 0.0, 1.0);

        break;

    case LowShelf:

        m_parameter1 = AudioParam::create("frequency", 80.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("gain", 0.0, 0.0, 1.0);

        m_parameter3 = AudioParam::create("unused", 0.0, 0.0, 1.0);

        break;

    case HighShelf:

        m_parameter1 = AudioParam::create("frequency", 10000.0, 20.0, nyquist);

        m_parameter2 = AudioParam::create("gain", 0.0, 0.0, 1.0);

        m_parameter3 = AudioParam::create("unused", 0.0, 0.0, 1.0);

        break;

    }

    if (autoInitialize)

        initialize();

}

BiquadProcessor::~BiquadProcessor()

{

    if (isInitialized())

        uninitialize();

}

PassOwnPtr<AudioDSPKernel> BiquadProcessor::createKernel()

{

    return adoptPtr(new BiquadDSPKernel(this));

}

void BiquadProcessor::process(AudioBus* source, AudioBus* destination, size_t framesToProcess)

{

    if (!isInitialized()) {

        destination->zero();

        return;

    }

    // Deal with smoothing / de-zippering.  Start out assuming filter parameters are not changing.

    // The BiquadDSPKernel objects rely on this value to see if they need to re-compute their internal filter coefficients.

    m_filterCoefficientsDirty = false;

    if (m_hasJustReset) {

        // Snap to exact values first time after reset, then smooth for subsequent changes.

        m_parameter1->resetSmoothedValue();

        m_parameter2->resetSmoothedValue();

        m_parameter3->resetSmoothedValue();

        m_filterCoefficientsDirty = true;

        m_hasJustReset = false;

    } else {

        // Smooth all of the filter parameters.  If they haven't yet converged to their target value then mark coefficients as dirty.

        bool isStable1 = m_parameter1->smooth();

        bool isStable2 = m_parameter2->smooth();

        bool isStable3 = m_parameter3->smooth();

        if (!(isStable1 && isStable2 && isStable3))

            m_filterCoefficientsDirty = true;

    }

    // For each channel of our input, process using the corresponding BiquadDSPKernel into the output channel.

    for (unsigned i = 0; i < m_kernels.size(); ++i)

        m_kernels[i]->process(source->channel(i)->data(), destination->channel(i)->data(), framesToProcess);

}

} // namespace WebCore

#endif // ENABLE(WEB_AUDIO)

/*

 * 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 BiquadProcessor_h

#define BiquadProcessor_h

#include "AudioDSPKernel.h"

#include "AudioDSPKernelProcessor.h"

#include "AudioNode.h"

#include "AudioParam.h"

#include "Biquad.h"

#include <wtf/RefPtr.h>

namespace WebCore {

// BiquadProcessor is an AudioDSPKernelProcessor which uses Biquad objects to implement several common filters.

class BiquadProcessor : public AudioDSPKernelProcessor {

public:

    enum FilterType {

        LowPass2,

        HighPass2,

        Peaking,

        Allpass,

        LowShelf,

        HighShelf

    };

    BiquadProcessor(FilterType, double sampleRate, size_t numberOfChannels, bool autoInitialize = true);

    virtual ~BiquadProcessor();

    virtual PassOwnPtr<AudioDSPKernel> createKernel();

    virtual void process(AudioBus* source, AudioBus* destination, size_t framesToProcess);

    bool filterCoefficientsDirty() const { return m_filterCoefficientsDirty; }

    AudioParam* parameter1() { return m_parameter1.get(); }

    AudioParam* parameter2() { return m_parameter2.get(); }

    AudioParam* parameter3() { return m_parameter3.get(); }

    FilterType type() const { return m_type; }

private:

    FilterType m_type;

    RefPtr<AudioParam> m_parameter1;

    RefPtr<AudioParam> m_parameter2;

    RefPtr<AudioParam> m_parameter3;

    // so DSP kernels know when to re-compute coefficients

    bool m_filterCoefficientsDirty;

};

} // namespace WebCore

#endif // BiquadProcessor_h