ref: a88594d54be34baa13566a417ed8b358eea439cd
dir: /src/spectral/fft.h/
/*
Copyright (C) 2003-2013 Paul Brossier <piem@aubio.org>
This file is part of aubio.
aubio 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 3 of the License, or
(at your option) any later version.
aubio is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with aubio. If not, see <http://www.gnu.org/licenses/>.
*/
/** \file
Fast Fourier Transform
Depending on how aubio was compiled, FFT are computed using one of:
- [Ooura](http://www.kurims.kyoto-u.ac.jp/~ooura/fft.html)
- [FFTW3](http://www.fftw.org)
- [vDSP](https://developer.apple.com/library/mac/#documentation/Accelerate/Reference/vDSPRef/Reference/reference.html)
\example spectral/test-fft.c
*/
#ifndef AUBIO_FFT_H
#define AUBIO_FFT_H
#ifdef __cplusplus
extern "C" {
#endif
/** FFT object
This object computes forward and backward FFTs.
*/
typedef struct _aubio_fft_t aubio_fft_t;
/** create new FFT computation object
\param size length of the FFT
*/
aubio_fft_t * new_aubio_fft (uint_t size);
/** delete FFT object
\param s fft object as returned by new_aubio_fft
*/
void del_aubio_fft(aubio_fft_t * s);
/** compute forward FFT
\param s fft object as returned by new_aubio_fft
\param input input signal
\param spectrum output spectrum
*/
void aubio_fft_do (aubio_fft_t *s, const fvec_t * input, cvec_t * spectrum);
/** compute backward (inverse) FFT
\param s fft object as returned by new_aubio_fft
\param spectrum input spectrum
\param output output signal
*/
void aubio_fft_rdo (aubio_fft_t *s, const cvec_t * spectrum, fvec_t * output);
/** compute forward FFT
\param s fft object as returned by new_aubio_fft
\param input real input signal
\param compspec complex output fft real/imag
*/
void aubio_fft_do_complex (aubio_fft_t *s, const fvec_t * input, fvec_t * compspec);
/** compute backward (inverse) FFT from real/imag
\param s fft object as returned by new_aubio_fft
\param compspec real/imag input fft array
\param output real output array
*/
void aubio_fft_rdo_complex (aubio_fft_t *s, const fvec_t * compspec, fvec_t * output);
/** convert real/imag spectrum to norm/phas spectrum
\param compspec real/imag input fft array
\param spectrum cvec norm/phas output array
*/
void aubio_fft_get_spectrum(const fvec_t * compspec, cvec_t * spectrum);
/** convert real/imag spectrum to norm/phas spectrum
\param compspec real/imag input fft array
\param spectrum cvec norm/phas output array
*/
void aubio_fft_get_realimag(const cvec_t * spectrum, fvec_t * compspec);
/** compute phas spectrum from real/imag parts
\param compspec real/imag input fft array
\param spectrum cvec norm/phas output array
*/
void aubio_fft_get_phas(const fvec_t * compspec, cvec_t * spectrum);
/** compute imaginary part from the norm/phas cvec
\param spectrum norm/phas input array
\param compspec real/imag output fft array
*/
void aubio_fft_get_imag(const cvec_t * spectrum, fvec_t * compspec);
/** compute norm component from real/imag parts
\param compspec real/imag input fft array
\param spectrum cvec norm/phas output array
*/
void aubio_fft_get_norm(const fvec_t * compspec, cvec_t * spectrum);
/** compute real part from norm/phas components
\param spectrum norm/phas input array
\param compspec real/imag output fft array
*/
void aubio_fft_get_real(const cvec_t * spectrum, fvec_t * compspec);
#ifdef __cplusplus
}
#endif
#endif /* AUBIO_FFT_H */