ref: dda6ba6b4a25ce34d40ce3f4b0c14ca2c95bc32a
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; }