BiquadFilterNode.cpp   [plain text]

/*
 * Copyright (C) 2011, Google Inc. All rights reserved.
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 *
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#include "config.h"

#if ENABLE(WEB_AUDIO)

#include "BiquadFilterNode.h"

#include "ExceptionCode.h"

namespace WebCore {

BiquadFilterNode::BiquadFilterNode(AudioContext* context, float sampleRate)
    : AudioBasicProcessorNode(context, sampleRate)
{
    // Initially setup as lowpass filter.
    m_processor = adoptPtr(new BiquadProcessor(sampleRate, 1, false));
    biquadProcessor()->parameter1()->setContext(context);
    biquadProcessor()->parameter2()->setContext(context);
    biquadProcessor()->parameter3()->setContext(context);
    setNodeType(NodeTypeBiquadFilter);
}

void BiquadFilterNode::setType(unsigned short type, ExceptionCode& ec)
{
    if (type > BiquadProcessor::Allpass) {
        ec = NOT_SUPPORTED_ERR;
        return;
    }
    
    biquadProcessor()->setType(static_cast<BiquadProcessor::FilterType>(type));
}


void BiquadFilterNode::getFrequencyResponse(const Float32Array* frequencyHz,
                                            Float32Array* magResponse,
                                            Float32Array* phaseResponse)
{
    if (!frequencyHz || !magResponse || !phaseResponse)
        return;
    
    int n = std::min(frequencyHz->length(),
                     std::min(magResponse->length(), phaseResponse->length()));

    if (n) {
        biquadProcessor()->getFrequencyResponse(n,
                                                frequencyHz->data(),
                                                magResponse->data(),
                                                phaseResponse->data());
    }
}

} // namespace WebCore

#endif // ENABLE(WEB_AUDIO)