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livetrax/libs/rubberband/src/FFT.h

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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
/*
Rubber Band
An audio time-stretching and pitch-shifting library.
Copyright 2007-2008 Chris Cannam.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version. See the file
COPYING included with this distribution for more information.
*/
#ifndef _RUBBERBAND_FFT_H_
#define _RUBBERBAND_FFT_H_
#include "sysutils.h"
namespace RubberBand {
class FFTImpl;
/**
* Provide the basic FFT computations we need, using one of a set of
* candidate FFT implementations (depending on compile flags).
*
* Implements real->complex FFTs of power-of-two sizes only. Note
* that only the first half of the output signal is returned (the
* complex conjugates half is omitted), so the "complex" arrays need
* room for size/2+1 elements.
*
* Not thread safe: use a separate instance per thread.
*/
class FFT
{
public:
enum Exception { InvalidSize };
FFT(int size, int debugLevel = 0); // may throw InvalidSize
~FFT();
void forward(const double *R__ realIn, double *R__ realOut, double *R__ imagOut);
void forwardPolar(const double *R__ realIn, double *R__ magOut, double *R__ phaseOut);
void forwardMagnitude(const double *R__ realIn, double *R__ magOut);
void forward(const float *R__ realIn, float *R__ realOut, float *R__ imagOut);
void forwardPolar(const float *R__ realIn, float *R__ magOut, float *R__ phaseOut);
void forwardMagnitude(const float *R__ realIn, float *R__ magOut);
void inverse(const double *R__ realIn, const double *R__ imagIn, double *R__ realOut);
void inversePolar(const double *R__ magIn, const double *R__ phaseIn, double *R__ realOut);
void inverseCepstral(const double *R__ magIn, double *R__ cepOut);
void inverse(const float *R__ realIn, const float *R__ imagIn, float *R__ realOut);
void inversePolar(const float *R__ magIn, const float *R__ phaseIn, float *R__ realOut);
void inverseCepstral(const float *R__ magIn, float *R__ cepOut);
// Calling one or both of these is optional -- if neither is
// called, the first call to a forward or inverse method will call
// init(). You only need call these if you don't want to risk
// expensive allocations etc happening in forward or inverse.
void initFloat();
void initDouble();
float *getFloatTimeBuffer();
double *getDoubleTimeBuffer();
static void tune();
protected:
FFTImpl *d;
static int m_method;
};
}
#endif