ref: 240e416b398b85f99c076e179734293ebc2cddfc
dir: /src/onset/peakpick.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 "fvec.h"
#include "mathutils.h"
#include "temporal/biquad.h"
#include "onset/peakpick.h"
/* peak picking parameters, default values in brackets
*
* [<----post----|--pre-->]
* .................|.............
* time-> ^now
*/
struct _aubio_peakpicker_t {
/** thresh: offset threshold [0.033 or 0.01] */
smpl_t threshold;
/** win_post: median filter window length (causal part) [8] */
uint_t win_post;
/** pre: median filter window (anti-causal part) [post-1] */
uint_t win_pre;
/** threshfn: name or handle of fn for computing adaptive threshold [median] */
aubio_thresholdfn_t thresholdfn;
/** picker: name or handle of fn for picking event times [peakpick] */
aubio_pickerfn_t pickerfn;
/** biquad lowpass filter */
aubio_biquad_t * biquad;
/** original onsets */
fvec_t * onset_keep;
/** modified onsets */
fvec_t * onset_proc;
/** peak picked window [3] */
fvec_t * onset_peek;
/** scratch pad for biquad and median */
fvec_t * scratch;
/** \bug should be used to calculate filter coefficients */
/* cutoff: low-pass filter cutoff [0.34, 1] */
/* smpl_t cutoff; */
/* not used anymore */
/* time precision [512/44100 winlength/samplerate, fs/buffer_size */
/* smpl_t tau; */
/* alpha: normalisation exponent [9] */
/* smpl_t alpha; */
};
/** modified version for real time, moving mean adaptive threshold this method
* is slightly more permissive than the offline one, and yelds to an increase
* of false positives. best */
smpl_t aubio_peakpicker_do(aubio_peakpicker_t * p, fvec_t * onset) {
fvec_t * onset_keep = (fvec_t *)p->onset_keep;
fvec_t * onset_proc = (fvec_t *)p->onset_proc;
fvec_t * onset_peek = (fvec_t *)p->onset_peek;
fvec_t * scratch = (fvec_t *)p->scratch;
smpl_t mean = 0., median = 0.;
smpl_t isonset = 0.;
uint_t length = p->win_post + p->win_pre + 1;
uint_t i = 0, j;
/* store onset in onset_keep */
/* shift all elements but last, then write last */
/* for (i=0;i<channels;i++) { */
for (j=0;j<length-1;j++) {
onset_keep->data[i][j] = onset_keep->data[i][j+1];
onset_proc->data[i][j] = onset_keep->data[i][j];
}
onset_keep->data[i][length-1] = onset->data[i][0];
onset_proc->data[i][length-1] = onset->data[i][0];
/* } */
/* filter onset_proc */
/** \bug filtfilt calculated post+pre times, should be only once !? */
aubio_biquad_do_filtfilt(p->biquad,onset_proc,scratch);
/* calculate mean and median for onset_proc */
/* for (i=0;i<onset_proc->channels;i++) { */
mean = fvec_mean(onset_proc);
/* copy to scratch */
for (j = 0; j < length; j++)
scratch->data[i][j] = onset_proc->data[i][j];
median = p->thresholdfn(scratch);
/* } */
/* for (i=0;i<onset->channels;i++) { */
/* shift peek array */
for (j=0;j<3-1;j++)
onset_peek->data[i][j] = onset_peek->data[i][j+1];
/* calculate new peek value */
onset_peek->data[i][2] =
onset_proc->data[i][p->win_post] - median - mean * p->threshold;
/* } */
//AUBIO_DBG("%f\n", onset_peek->data[0][2]);
isonset = (p->pickerfn)(onset_peek,1);
if (isonset) { //(isonset) {
isonset = fvec_quadint(onset_peek, 1, 1);
}
return isonset;
}
/** this method returns the current value in the pick peaking buffer
* after smoothing
*/
smpl_t aubio_peakpicker_get_thresholded_input(aubio_peakpicker_t * p)
{
return p->onset_peek->data[0][1];
}
/** function added by Miguel Ramirez to return the onset detection amplitude in peakval */
uint_t aubio_peakpicker_set_threshold(aubio_peakpicker_t * p, smpl_t threshold) {
p->threshold = threshold;
return AUBIO_OK;
}
smpl_t aubio_peakpicker_get_threshold(aubio_peakpicker_t * p) {
return p->threshold;
}
uint_t aubio_peakpicker_set_thresholdfn(aubio_peakpicker_t * p, aubio_thresholdfn_t thresholdfn) {
p->thresholdfn = thresholdfn;
return AUBIO_OK;
}
aubio_thresholdfn_t aubio_peakpicker_get_thresholdfn(aubio_peakpicker_t * p) {
return (aubio_thresholdfn_t) (p->thresholdfn);
}
aubio_peakpicker_t * new_aubio_peakpicker(smpl_t threshold) {
aubio_peakpicker_t * t = AUBIO_NEW(aubio_peakpicker_t);
t->threshold = 0.1; /* 0.0668; 0.33; 0.082; 0.033; */
if (threshold > 0. && threshold < 10.)
t->threshold = threshold;
t->win_post = 5;
t->win_pre = 1;
t->thresholdfn = (aubio_thresholdfn_t)(fvec_median); /* (fvec_mean); */
t->pickerfn = (aubio_pickerfn_t)(fvec_peakpick);
t->scratch = new_fvec(t->win_post+t->win_pre+1,1);
t->onset_keep = new_fvec(t->win_post+t->win_pre+1,1);
t->onset_proc = new_fvec(t->win_post+t->win_pre+1,1);
t->onset_peek = new_fvec(3,1);
/* cutoff: low-pass filter cutoff [0.34, 1] */
/* t->cutoff=0.34; */
t->biquad = new_aubio_biquad(0.1600,0.3200,0.1600,-0.5949,0.2348);
return t;
}
void del_aubio_peakpicker(aubio_peakpicker_t * p) {
del_aubio_biquad(p->biquad);
del_fvec(p->onset_keep);
del_fvec(p->onset_proc);
del_fvec(p->onset_peek);
del_fvec(p->scratch);
AUBIO_FREE(p);
}