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29 #ifndef FFTConvolver_h
30 #define FFTConvolver_h
32 #include "platform/audio/AudioArray.h"
33 #include "platform/audio/FFTFrame.h"
37 class PLATFORM_EXPORT FFTConvolver {
39 // fftSize must be a power of two
40 FFTConvolver(size_t fftSize);
42 // For now, with multiple calls to Process(), framesToProcess MUST add up EXACTLY to fftSize / 2
44 // FIXME: Later, we can do more sophisticated buffering to relax this requirement...
46 // The input to output latency is equal to fftSize / 2
48 // Processing in-place is allowed...
49 void process(FFTFrame* fftKernel, const float* sourceP, float* destP, size_t framesToProcess);
53 size_t fftSize() const { return m_frame.fftSize(); }
58 // Buffer input until we get fftSize / 2 samples then do an FFT
59 size_t m_readWriteIndex;
60 AudioFloatArray m_inputBuffer;
62 // Stores output which we read a little at a time
63 AudioFloatArray m_outputBuffer;
65 // Saves the 2nd half of the FFT buffer, so we can do an overlap-add with the 1st half of the next one
66 AudioFloatArray m_lastOverlapBuffer;
71 #endif // FFTConvolver_h