root/BiquadFilterNode.h

INCLUDED FROM

/*
 * Copyright (C) 2011, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
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 *    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
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 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
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#ifndef BiquadFilterNode_h
#define BiquadFilterNode_h

#include "modules/webaudio/AudioBasicProcessorNode.h"
#include "modules/webaudio/BiquadProcessor.h"

namespace WebCore {

class AudioParam;

class BiquadFilterNode : public AudioBasicProcessorNode {
public:
    // These must be defined as in the .idl file and must match those in the BiquadProcessor class.
    enum {
        LOWPASS = 0,
        HIGHPASS = 1,
        BANDPASS = 2,
        LOWSHELF = 3,
        HIGHSHELF = 4,
        PEAKING = 5,
        NOTCH = 6,
        ALLPASS = 7
    };

    static PassRefPtr<BiquadFilterNode> create(AudioContext* context, float sampleRate)
    {
        return adoptRef(new BiquadFilterNode(context, sampleRate));
    }

    String type() const;
    bool setType(unsigned); // Returns true on success.
    void setType(const String&);

    AudioParam* frequency() { return biquadProcessor()->parameter1(); }
    AudioParam* q() { return biquadProcessor()->parameter2(); }
    AudioParam* gain() { return biquadProcessor()->parameter3(); }
    AudioParam* detune() { return biquadProcessor()->parameter4(); }

    // Get the magnitude and phase response of the filter at the given
    // set of frequencies (in Hz). The phase response is in radians.
    void getFrequencyResponse(const Float32Array* frequencyHz,
                              Float32Array* magResponse,
                              Float32Array* phaseResponse);

private:
    BiquadFilterNode(AudioContext*, float sampleRate);

    BiquadProcessor* biquadProcessor() { return static_cast<BiquadProcessor*>(processor()); }
};

} // namespace WebCore

#endif // BiquadFilterNode_h