andrew@0: /*
andrew@0: 	 Copyright (C) 2003 Paul Brossier
andrew@0: 
andrew@0: 	 This program is free software; you can redistribute it and/or modify
andrew@0: 	 it under the terms of the GNU General Public License as published by
andrew@0: 	 the Free Software Foundation; either version 2 of the License, or
andrew@0: 	 (at your option) any later version.
andrew@0: 
andrew@0: 	 This program is distributed in the hope that it will be useful,
andrew@0: 	 but WITHOUT ANY WARRANTY; without even the implied warranty of
andrew@0: 	 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
andrew@0: 	 GNU General Public License for more details.
andrew@0: 
andrew@0: 	 You should have received a copy of the GNU General Public License
andrew@0: 	 along with this program; if not, write to the Free Software
andrew@0: 	 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
andrew@0: 	 
andrew@0: */
andrew@0: 
andrew@0: /** \file 
andrew@0: 
andrew@0:   Fast Fourier Transform object
andrew@0: 
andrew@0: */
andrew@0: 
andrew@0: #ifndef FFT_H_
andrew@0: #define FFT_H_
andrew@0: 
andrew@0: /* note that <complex.h> is not included here but only in aubio_priv.h, so that
andrew@0:  * c++ projects can still use their own complex definition. */
andrew@0: #include <fftw3.h>
andrew@0: 
andrew@0: #ifdef HAVE_COMPLEX_H
andrew@0: #if FFTW3F_SUPPORT
andrew@0: #define FFTW_TYPE fftwf_complex
andrew@0: #else
andrew@0: #define FFTW_TYPE fftw_complex
andrew@0: #endif
andrew@0: #else
andrew@0: #if FFTW3F_SUPPORT
andrew@0: /** fft data type */
andrew@0: #define FFTW_TYPE float
andrew@0: #else
andrew@0: /** fft data type */
andrew@0: #define FFTW_TYPE double
andrew@0: #endif
andrew@0: #endif
andrew@0: 
andrew@0: #ifdef __cplusplus
andrew@0: extern "C" {
andrew@0: #endif
andrew@0: 
andrew@0: /** fft data type */
andrew@0: typedef FFTW_TYPE fft_data_t;
andrew@0: 
andrew@0: /** FFT object
andrew@0:  
andrew@0:   This object computes forward and backward FFTs, using the complex type to
andrew@0:   store the results. The phase vocoder or aubio_mfft_t objects should be
andrew@0:   preferred to using directly aubio_fft_t. The FFT are computed using FFTW3
andrew@0:   (although support for another library could be added).
andrew@0: 
andrew@0: */
andrew@0: typedef struct _aubio_fft_t aubio_fft_t;
andrew@0: 
andrew@0: /** create new FFT computation object
andrew@0: 
andrew@0:   \param size length of the FFT
andrew@0: 
andrew@0: */
andrew@0: aubio_fft_t * new_aubio_fft(ba_uint_t size);
andrew@0: /** delete FFT object 
andrew@0: 
andrew@0:   \param s fft object as returned by new_aubio_fft
andrew@0: 
andrew@0: */
andrew@0: void del_aubio_fft(aubio_fft_t * s);
andrew@0: /** compute forward FFT
andrew@0: 
andrew@0:   \param s fft object as returned by new_aubio_fft
andrew@0:   \param data input signal 
andrew@0:   \param spectrum output spectrum 
andrew@0:   \param size length of the input vector 
andrew@0: 
andrew@0: */
andrew@0: void aubio_fft_do (const aubio_fft_t *s, const smpl_t * data,
andrew@0:     fft_data_t * spectrum, const ba_uint_t size);
andrew@0: /** compute backward (inverse) FFT
andrew@0: 
andrew@0:   \param s fft object as returned by new_aubio_fft
andrew@0:   \param spectrum input spectrum 
andrew@0:   \param data output signal 
andrew@0:   \param size length of the input vector 
andrew@0: 
andrew@0: */
andrew@0: void aubio_fft_rdo(const aubio_fft_t *s, const fft_data_t * spectrum,
andrew@0:     smpl_t * data, const ba_uint_t size);
andrew@0: /** compute norm vector from input spectrum
andrew@0: 
andrew@0:   \param norm magnitude vector output
andrew@0:   \param spectrum spectral data input
andrew@0:   \param size size of the vectors
andrew@0: 
andrew@0: */
andrew@0: void aubio_fft_getnorm(smpl_t * norm, fft_data_t * spectrum, ba_uint_t size);
andrew@0: /** compute phase vector from input spectrum 
andrew@0:  
andrew@0:   \param phase phase vector output
andrew@0:   \param spectrum spectral data input
andrew@0:   \param size size of the vectors
andrew@0: 
andrew@0: */
andrew@0: void aubio_fft_getphas(smpl_t * phase, fft_data_t * spectrum, ba_uint_t size);
andrew@0: 
andrew@0: /** FFT object (using cvec)
andrew@0: 
andrew@0:   This object works similarly as aubio_fft_t, except the spectral data is
andrew@0:   stored in a cvec_t as two vectors, magnitude and phase. 
andrew@0: 
andrew@0: */
andrew@0: typedef struct _aubio_mfft_t aubio_mfft_t;
andrew@0: 
andrew@0: /** create new FFT computation object
andrew@0: 
andrew@0:   \param winsize length of the FFT
andrew@0:   \param channels number of channels 
andrew@0: 
andrew@0: */
andrew@0: aubio_mfft_t * new_aubio_mfft(ba_uint_t winsize, ba_uint_t channels);
andrew@0: /** compute forward FFT
andrew@0: 
andrew@0:   \param fft fft object as returned by new_aubio_mfft
andrew@0:   \param in input signal 
andrew@0:   \param fftgrain output spectrum
andrew@0: 
andrew@0: */
andrew@0: void aubio_mfft_do (aubio_mfft_t * fft,fvec_t * in,cvec_t * fftgrain);
andrew@0: /** compute backward (inverse) FFT
andrew@0: 
andrew@0:   \param fft fft object as returned by new_aubio_mfft
andrew@0:   \param fftgrain input spectrum (cvec) 
andrew@0:   \param out output signal 
andrew@0: 
andrew@0: */
andrew@0: void aubio_mfft_rdo(aubio_mfft_t * fft,cvec_t * fftgrain, fvec_t * out);
andrew@0: /** delete FFT object 
andrew@0: 
andrew@0:   \param fft fft object as returned by new_aubio_mfft
andrew@0: 
andrew@0: */
andrew@0: void del_aubio_mfft(aubio_mfft_t * fft);
andrew@0: 
andrew@0: 
andrew@0: #ifdef __cplusplus
andrew@0: }
andrew@0: #endif
andrew@0: 
andrew@0: #endif