ref: 32669d979d3b61b852591e63f7ea818e6a7e286b
dir: /src/phasevoc.c/
/*
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 "aubio_priv.h"
#include "sample.h"
#include "fft.h"
#include "mathutils.h"
#include "phasevoc.h"
/** phasevocoder internal object */
struct _aubio_pvoc_t {
/** grain length */
uint_t win_s;
/** overlap step */
uint_t hop_s;
/** number of channels */
uint_t channels;
/** spectral data */
aubio_mfft_t * fft;
/**cur output grain [win_s] */
fvec_t * synth;
/**last input frame [win_s-hop_s] */
fvec_t * synthold;
/**current input grain [win_s] */
fvec_t * data;
/**last input frame [win_s-hop_s] */
fvec_t * dataold;
/** grain window [win_s] */
float * w;
};
/** returns data and dataold slided by hop_s */
static void aubio_pvoc_swapbuffers(
smpl_t * data,
smpl_t * dataold,
const smpl_t * datanew,
uint_t win_s, uint_t hop_s);
/** do additive synthesis from 'old' and 'cur' */
static void aubio_pvoc_addsynth(
const smpl_t * synth,
smpl_t * synthold,
smpl_t * synthnew,
uint_t win_s, uint_t hop_s);
void aubio_pvoc_do(aubio_pvoc_t *pv, fvec_t * datanew, cvec_t *fftgrain) {
uint_t i,j;
for (i=0; i<pv->channels; i++) {
/* slide */
aubio_pvoc_swapbuffers(pv->data->data[i],pv->dataold->data[i],
datanew->data[i],pv->win_s,pv->hop_s);
/* windowing */
for (j=0; j<pv->win_s; j++) pv->data->data[i][j] *= pv->w[j];
}
/* shift */
vec_shift(pv->data);
/* calculate fft */
aubio_mfft_do (pv->fft,pv->data,fftgrain);
}
void aubio_pvoc_rdo(aubio_pvoc_t *pv,cvec_t * fftgrain, fvec_t * synthnew) {
uint_t i,j;
/* calculate rfft */
aubio_mfft_rdo(pv->fft,fftgrain,pv->synth);
/* unshift */
vec_shift(pv->synth);
for (i=0; i<pv->channels; i++) {
for (j=0; j<pv->win_s; j++) pv->synth->data[i][j] *= pv->w[j];
aubio_pvoc_addsynth(pv->synth->data[i],pv->synthold->data[i],
synthnew->data[i],pv->win_s,pv->hop_s);
}
}
aubio_pvoc_t * new_aubio_pvoc (uint_t win_s, uint_t hop_s, uint_t channels) {
aubio_pvoc_t * pv = AUBIO_NEW(aubio_pvoc_t);
if (win_s < 2*hop_s) {
AUBIO_ERR("Hop size bigger than half the window size!\n");
AUBIO_ERR("Resetting hop size to half the window size.\n");
hop_s = win_s / 2;
}
if (hop_s < 1) {
AUBIO_ERR("Hop size is smaller than 1!\n");
AUBIO_ERR("Resetting hop size to half the window size.\n");
hop_s = win_s / 2;
}
pv->fft = new_aubio_mfft(win_s,channels);
/* remember old */
pv->data = new_fvec (win_s, channels);
pv->synth = new_fvec (win_s, channels);
/* new input output */
pv->dataold = new_fvec (win_s-hop_s, channels);
pv->synthold = new_fvec (win_s-hop_s, channels);
pv->w = AUBIO_ARRAY(smpl_t,win_s);
window(pv->w,win_s,aubio_win_hanningz);
pv->channels = channels;
pv->hop_s = hop_s;
pv->win_s = win_s;
return pv;
}
void del_aubio_pvoc(aubio_pvoc_t *pv) {
del_fvec(pv->data);
del_fvec(pv->synth);
del_fvec(pv->dataold);
del_fvec(pv->synthold);
AUBIO_FREE(pv->w);
AUBIO_FREE(pv);
}
static void aubio_pvoc_swapbuffers(smpl_t * data, smpl_t * dataold,
const smpl_t * datanew, uint_t win_s, uint_t hop_s)
{
uint_t i;
for (i=0;i<win_s-hop_s;i++)
data[i] = dataold[i];
for (i=0;i<hop_s;i++)
data[win_s-hop_s+i] = datanew[i];
for (i=0;i<win_s-hop_s;i++)
dataold[i] = data[i+hop_s];
}
static void aubio_pvoc_addsynth(const smpl_t * synth, smpl_t * synthold,
smpl_t * synthnew, uint_t win_s, uint_t hop_s)
{
uint_t i;
smpl_t scale = 2*hop_s/(win_s+.0);
/* add new synth to old one and put result in synthnew */
for (i=0;i<hop_s;i++)
synthnew[i] = synthold[i]+synth[i]*scale;
/* shift synthold */
for (i=0;i<win_s-2*hop_s;i++)
synthold[i] = synthold[i+hop_s];
/* erase last frame in synthold */
for (i=win_s-hop_s;i<win_s;i++)
synthold[i-hop_s]=0.;
/* additive synth */
for (i=0;i<win_s-hop_s;i++)
synthold[i] += synth[i+hop_s]*scale;
}