ref: d3b1eb196325b80ad269ca74456b8f08d1ea4f27
dir: /src/spectral/phasevoc.c/
/*
Copyright (C) 2003-2009 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/>.
*/
#include "aubio_priv.h"
#include "fvec.h"
#include "cvec.h"
#include "mathutils.h"
#include "spectral/fft.h"
#include "spectral/phasevoc.h"
/** phasevocoder internal object */
struct _aubio_pvoc_t {
uint_t win_s; /** grain length */
uint_t hop_s; /** overlap step */
aubio_fft_t * fft; /** fft object */
fvec_t * synth; /** cur output grain [win_s] */
fvec_t * synthold; /** last input frame [win_s-hop_s] */
fvec_t * data; /** current input grain [win_s] */
fvec_t * dataold; /** last input frame [win_s-hop_s] */
fvec_t * w; /** grain window [win_s] */
};
/** 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) {
/* slide */
aubio_pvoc_swapbuffers(pv->data->data,pv->dataold->data,
datanew->data,pv->win_s,pv->hop_s);
/* windowing */
fvec_weight(pv->data, pv->w);
/* shift */
fvec_shift(pv->data);
/* calculate fft */
aubio_fft_do (pv->fft,pv->data,fftgrain);
}
void aubio_pvoc_rdo(aubio_pvoc_t *pv,cvec_t * fftgrain, fvec_t * synthnew) {
/* calculate rfft */
aubio_fft_rdo(pv->fft,fftgrain,pv->synth);
/* unshift */
fvec_shift(pv->synth);
aubio_pvoc_addsynth(pv->synth->data,pv->synthold->data,
synthnew->data,pv->win_s,pv->hop_s);
}
aubio_pvoc_t * new_aubio_pvoc (uint_t win_s, uint_t hop_s) {
aubio_pvoc_t * pv = AUBIO_NEW(aubio_pvoc_t);
/* if (win_s < 2*hop_s) {
AUBIO_WRN("Hop size bigger than half the window size!\n");
} */
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_fft (win_s);
/* remember old */
pv->data = new_fvec (win_s);
pv->synth = new_fvec (win_s);
/* new input output */
pv->dataold = new_fvec (win_s-hop_s);
pv->synthold = new_fvec (win_s-hop_s);
pv->w = new_aubio_window ("hanningz", win_s);
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);
del_fvec(pv->w);
del_aubio_fft(pv->fft);
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;
}