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 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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#ifndef AudioDSPKernel_h
#define AudioDSPKernel_h

#include "AudioDSPKernelProcessor.h"

namespace WebCore {

// AudioDSPKernel does the processing for one channel of an AudioDSPKernelProcessor.

class AudioDSPKernel {
    WTF_MAKE_NONCOPYABLE(AudioDSPKernel);
    WTF_MAKE_FAST_ALLOCATED;
public:
    AudioDSPKernel(AudioDSPKernelProcessor* kernelProcessor)
        : m_kernelProcessor(kernelProcessor)
        , m_sampleRate(kernelProcessor->sampleRate())
    {
    }

    AudioDSPKernel(float sampleRate)
        : m_kernelProcessor(0)
        , m_sampleRate(sampleRate)
    {
    }

    virtual ~AudioDSPKernel() { };

    // Subclasses must override process() to do the processing and reset() to reset DSP state.
    virtual void process(const float* source, float* destination, size_t framesToProcess) = 0;

    // Subclasses that have AudioParams must override this to process the AudioParams.
    virtual void processOnlyAudioParams(size_t) { }

    virtual void reset() = 0;

    float sampleRate() const { return m_sampleRate; }
    double nyquist() const { return 0.5 * sampleRate(); }

    AudioDSPKernelProcessor* processor() { return m_kernelProcessor; }
    const AudioDSPKernelProcessor* processor() const { return m_kernelProcessor; }

    virtual double tailTime() const = 0;
    virtual double latencyTime() const = 0;
    virtual bool requiresTailProcessing() const = 0;

protected:
    AudioDSPKernelProcessor* m_kernelProcessor;
    float m_sampleRate;
};

} // namespace WebCore

#endif // AudioDSPKernel_h