Source/platform/audio/AudioDSPKernel.h

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#ifndef AudioDSPKernel_h
#define AudioDSPKernel_h

#include "platform/audio/AudioDSPKernelProcessor.h"

namespace WebCore {

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

class PLATFORM_EXPORT AudioDSPKernel {
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;
    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;

protected:
    AudioDSPKernelProcessor* m_kernelProcessor;
    float m_sampleRate;
};

} // namespace WebCore

#endif // AudioDSPKernel_h