Source/WebCore/Modules/webaudio/WaveShaperProcessor.h

/*
 * Copyright (C) 2011, Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
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 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
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#pragma once

#include "AudioDSPKernel.h"
#include "AudioDSPKernelProcessor.h"
#include "AudioNode.h"
#include <JavaScriptCore/Float32Array.h>
#include <memory>
#include <wtf/Lock.h>
#include <wtf/RefPtr.h>

namespace WebCore {

// WaveShaperProcessor is an AudioDSPKernelProcessor which uses WaveShaperDSPKernel objects to implement non-linear distortion effects.

class WaveShaperProcessor : public AudioDSPKernelProcessor {
public:
    enum OverSampleType {
        OverSampleNone,
        OverSample2x,
        OverSample4x
    };

    WaveShaperProcessor(float sampleRate, size_t numberOfChannels);

    virtual ~WaveShaperProcessor();

    std::unique_ptr<AudioDSPKernel> createKernel() override;

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

    void setCurve(Float32Array*);
    Float32Array* curve() { return m_curve.get(); }

    void setOversample(OverSampleType);
    OverSampleType oversample() const { return m_oversample; }

private:
    // m_curve represents the non-linear shaping curve.
    RefPtr<Float32Array> m_curve;

    OverSampleType m_oversample;

    // This synchronizes process() with setCurve().
    mutable Lock m_processMutex;
};

} // namespace WebCore