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25 #ifndef BiquadDSPKernel_h
26 #define BiquadDSPKernel_h
28 #include "platform/audio/AudioDSPKernel.h"
29 #include "platform/audio/Biquad.h"
30 #include "modules/webaudio/BiquadProcessor.h"
34 class BiquadProcessor;
36 // BiquadDSPKernel is an AudioDSPKernel and is responsible for filtering one channel of a BiquadProcessor using a Biquad object.
38 class BiquadDSPKernel FINAL : public AudioDSPKernel {
40 explicit BiquadDSPKernel(BiquadProcessor* processor)
41 : AudioDSPKernel(processor)
46 virtual void process(const float* source, float* dest, size_t framesToProcess) OVERRIDE;
47 virtual void reset() OVERRIDE { m_biquad.reset(); }
49 // Get the magnitude and phase response of the filter at the given
50 // set of frequencies (in Hz). The phase response is in radians.
51 void getFrequencyResponse(int nFrequencies,
52 const float* frequencyHz,
54 float* phaseResponse);
56 virtual double tailTime() const OVERRIDE;
57 virtual double latencyTime() const OVERRIDE;
61 BiquadProcessor* biquadProcessor() { return static_cast<BiquadProcessor*>(processor()); }
63 // To prevent audio glitches when parameters are changed,
64 // dezippering is used to slowly change the parameters.
65 void updateCoefficientsIfNecessary();
66 // Update the biquad cofficients with the given parameters
67 void updateCoefficients(double frequency, double Q, double gain, double detune);
70 // Synchronize process() with getting and setting the filter coefficients.
71 mutable Mutex m_processLock;
76 #endif // BiquadDSPKernel_h