130 lines
4.7 KiB
C++
130 lines
4.7 KiB
C++
/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
|
|
|
|
/*
|
|
Rubber Band Library
|
|
An audio time-stretching and pitch-shifting library.
|
|
Copyright 2007-2018 Particular Programs Ltd.
|
|
|
|
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.
|
|
|
|
Alternatively, if you have a valid commercial licence for the
|
|
Rubber Band Library obtained by agreement with the copyright
|
|
holders, you may redistribute and/or modify it under the terms
|
|
described in that licence.
|
|
|
|
If you wish to distribute code using the Rubber Band Library
|
|
under terms other than those of the GNU General Public License,
|
|
you must obtain a valid commercial licence before doing so.
|
|
*/
|
|
|
|
#ifndef _RUBBERBAND_FFT_H_
|
|
#define _RUBBERBAND_FFT_H_
|
|
|
|
#include "system/sysutils.h"
|
|
|
|
#include <string>
|
|
#include <set>
|
|
|
|
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.
|
|
*
|
|
* The "interleaved" functions use the format sometimes called CCS --
|
|
* size/2+1 real+imaginary pairs. So, the array elements at indices 1
|
|
* and size+1 will always be zero (since the signal is real).
|
|
*
|
|
* All pointer arguments must point to valid data. A NullArgument
|
|
* exception is thrown if any argument is NULL.
|
|
*
|
|
* Neither forward nor inverse transform is scaled.
|
|
*
|
|
* This class is reentrant but not thread safe: use a separate
|
|
* instance per thread, or use a mutex.
|
|
*/
|
|
class FFT
|
|
{
|
|
public:
|
|
enum Exception {
|
|
NullArgument, InvalidSize, InvalidImplementation, InternalError
|
|
};
|
|
|
|
FFT(int size, int debugLevel = 0); // may throw InvalidSize
|
|
~FFT();
|
|
|
|
void forward(const double *R__ realIn, double *R__ realOut, double *R__ imagOut);
|
|
void forwardInterleaved(const double *R__ realIn, double *R__ complexOut);
|
|
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 forwardInterleaved(const float *R__ realIn, float *R__ complexOut);
|
|
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 inverseInterleaved(const double *R__ complexIn, 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 inverseInterleaved(const float *R__ complexIn, 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();
|
|
|
|
enum Precision {
|
|
SinglePrecision = 0x1,
|
|
DoublePrecision = 0x2
|
|
};
|
|
typedef int Precisions;
|
|
|
|
/**
|
|
* Return the OR of all precisions supported by this
|
|
* implementation. All of the functions (float and double) are
|
|
* available regardless of the supported implementations, but they
|
|
* will be calculated at the proper precision only if it is
|
|
* available. (So float functions will be calculated using doubles
|
|
* and then truncated if single-precision is unavailable, and
|
|
* double functions will use single-precision arithmetic if double
|
|
* is unavailable.)
|
|
*/
|
|
Precisions getSupportedPrecisions() const;
|
|
|
|
static std::set<std::string> getImplementations();
|
|
static std::string getDefaultImplementation();
|
|
static void setDefaultImplementation(std::string);
|
|
|
|
#ifdef FFT_MEASUREMENT
|
|
static std::string tune();
|
|
#endif
|
|
|
|
protected:
|
|
FFTImpl *d;
|
|
static std::string m_implementation;
|
|
static void pickDefaultImplementation();
|
|
};
|
|
|
|
}
|
|
|
|
#endif
|
|
|