source: src/resample.c @ 220dcfc

/*
         Copyright (C) 2003 Paul Brossier

         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.
         
*/


#include <samplerate.h> /* from libsamplerate */

#include "aubio_priv.h"
#include "sample.h"
#include "resample.h"

struct _aubio_resampler_t {
        SRC_DATA        *proc;
        SRC_STATE *stat;
        float ratio;
        uint_t type;
};

aubio_resampler_t * new_aubio_resampler(float ratio, uint_t type) {
        aubio_resampler_t * s  = AUBIO_NEW(aubio_resampler_t);
        sint_t error = 0;
        s->stat = src_new (type, 1, (sint_t*)error) ; /* only one channel */
        s->proc = AUBIO_NEW(SRC_DATA);
        if (error) AUBIO_ERR("%s\n",src_strerror(error));
        s->ratio = ratio;
        return s;
}

void del_aubio_resampler(aubio_resampler_t *s) {
        src_delete(s->stat);
        AUBIO_FREE(s);
}

uint_t aubio_resampler_process(aubio_resampler_t *s, 
    fvec_t * input,  fvec_t * output) {
        uint_t i ;
        s->proc->input_frames = input->length;
        s->proc->output_frames = output->length;
        s->proc->src_ratio = s->ratio;
        for (i = 0 ; i< input->channels; i++) 
        {
                /* make SRC_PROC data point to input outputs */
                s->proc->data_in = input->data[i];
                s->proc->data_out= output->data[i];
                /* do resampling */
                src_process (s->stat, s->proc) ;
        }
        return AUBIO_OK;
}