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28 #include "DelayDSPKernel.h"
29 #include "FFTConvolver.h"
34 class HRTFPanner : public Panner {
36 explicit HRTFPanner(double sampleRate);
37 virtual ~HRTFPanner();
40 virtual void pan(double azimuth, double elevation, AudioBus* inputBus, AudioBus* outputBus, size_t framesToProcess);
43 size_t fftSize() { return fftSizeForSampleRate(m_sampleRate); }
44 static size_t fftSizeForSampleRate(double sampleRate);
46 double sampleRate() const { return m_sampleRate; }
49 // Given an azimuth angle in the range -180 -> +180, returns the corresponding azimuth index for the database,
50 // and azimuthBlend which is an interpolation value from 0 -> 1.
51 int calculateDesiredAzimuthIndexAndBlend(double azimuth, double& azimuthBlend);
55 // m_isFirstRender and m_azimuthIndex are used to avoid harshly changing from rendering at one azimuth angle to another angle very far away.
56 // Changing the azimuth gradually produces a smoother sound.
60 FFTConvolver m_convolverL;
61 FFTConvolver m_convolverR;
62 DelayDSPKernel m_delayLineL;
63 DelayDSPKernel m_delayLineR;
66 } // namespace WebCore
68 #endif // HRTFPanner_h