ref: 21bd43cd56c206a650d48e79d966bd4c40dff3dd
dir: /src/filterbank.h/
/*
Copyright (C) 2007 Amaury Hazan
adapted to aubio from LibXtract
http://libxtract.sourceforge.net/
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.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/** \file
Filterbank object
General-purpose spectral filterbank object. Comes with mel-filter initialization function.
*/
#ifndef AUBIOFILTERBANK_H
#define AUBIOFILTERBANK_H
#ifdef __cplusplus
extern "C" {
#endif
typedef struct aubio_filterbank_t_ aubio_filterbank_t;
/** create filterbank object
\param win_s size of analysis buffer (and length the FFT transform)
\param n_filters number of filters to create
*/
aubio_filterbank_t * new_aubio_filterbank(uint_t n_filters, uint_t win_s);
/** destroy filterbank object
\param fb filterbank, as returned by new_aubio_filterbank method
*/
void del_aubio_filterbank(aubio_filterbank_t * fb);
/** filterbank initialization for mel filters
\param fb filterbank, as returned by new_aubio_filterbank method
\param nyquist nyquist frequency, i.e. half of the sampling rate
\param style libxtract style
\param freqmin lowest filter frequency
\param freqmax highest filter frequency
*/
void aubio_filterbank_mfcc_init(aubio_filterbank_t * fb, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max);
// Initialization
/** \brief A function to initialise a mel filter bank
*
* It is up to the caller to pass in a pointer to memory allocated for freq_bands arrays of length N. This function populates these arrays with magnitude coefficients representing the mel filterbank on a linear scale
*/
int aubio_mfcc_init(int N, smpl_t nyquist, int style, smpl_t freq_min, smpl_t freq_max, int freq_bands, smpl_t ** fft_tables);
#ifdef __cplusplus
}
#endif
#endif