root/DelayDSPKernel.h

INCLUDED FROM

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#ifndef DelayDSPKernel_h
#define DelayDSPKernel_h

#include "core/platform/audio/AudioArray.h"
#include "core/platform/audio/AudioDSPKernel.h"
#include "modules/webaudio/DelayProcessor.h"

namespace WebCore {

class DelayProcessor;

class DelayDSPKernel : public AudioDSPKernel {
public:
    explicit DelayDSPKernel(DelayProcessor*);
    DelayDSPKernel(double maxDelayTime, float sampleRate);

    virtual void process(const float* source, float* destination, size_t framesToProcess);
    virtual void reset();

    double maxDelayTime() const { return m_maxDelayTime; }

    void setDelayFrames(double numberOfFrames) { m_desiredDelayFrames = numberOfFrames; }

    virtual double tailTime() const OVERRIDE;
    virtual double latencyTime() const OVERRIDE;

private:
    AudioFloatArray m_buffer;
    double m_maxDelayTime;
    int m_writeIndex;
    double m_currentDelayTime;
    double m_smoothingRate;
    bool m_firstTime;
    double m_desiredDelayFrames;

    AudioFloatArray m_delayTimes;

    DelayProcessor* delayProcessor() { return static_cast<DelayProcessor*>(processor()); }
    size_t bufferLengthForDelay(double delayTime, double sampleRate) const;
};

} // namespace WebCore

#endif // DelayDSPKernel_h