source: src/hist.c @ d3efa4e

/*
         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 "scale.h"
#include "mathutils.h" //vec_min vec_max
#include "hist.h"

/********
 * Object Structure
 */

struct _aubio_hist_t {
        /*bug: move to a fvec */
        smpl_t ** hist;
        uint_t nelems;
        uint_t channels;
        smpl_t * cent;
        aubio_scale_t *scaler;
};


/********************************************************
 * Object Memory Allocation
 */

static aubio_hist_t * aubio_hist_malloc(uint_t channels, uint_t nelems);
static void aubio_hist_free(aubio_hist_t * s);

aubio_hist_t * aubio_hist_malloc(uint_t channels, uint_t nelems) {
        uint_t i;
        aubio_hist_t * s = AUBIO_NEW(aubio_hist_t);
        s->channels = channels;
        s->nelems = nelems;
        
        s->hist = AUBIO_ARRAY(smpl_t*, channels);
        for (i=0; i< s->channels; i++) {
                s->hist[i] = AUBIO_ARRAY(smpl_t, nelems);
        }
        s->cent = AUBIO_ARRAY(smpl_t, nelems);
        return s;
}

void aubio_hist_free(aubio_hist_t * s) {
        AUBIO_FREE(s);
}

/***
 * Object creation/deletion calls
 */
aubio_hist_t * new_aubio_hist (smpl_t ilow, smpl_t ihig, uint_t nelems, uint_t channels){
        smpl_t step = (ihig-ilow)/(smpl_t)(nelems);
        smpl_t accum = step;
        uint_t i;
        aubio_hist_t * s = aubio_hist_malloc(channels, nelems);
        
        /* use scale to map ilow/ihig -> 0/nelems */
        s->scaler = new_aubio_scale(ilow,ihig,0,nelems);
        /* calculate centers now once */
        s->cent[0] = ilow + 0.5 * step;
        for (i=1; i < s->nelems; i++, accum+=step )
                s->cent[i] = s->cent[0] + accum;
        
        return s;       
}

void del_aubio_hist(aubio_hist_t *s) {
        aubio_hist_free(s);
}

/***
 * do it
 */
void aubio_hist_do (aubio_hist_t *s, fvec_t *input) 
{
        uint_t i,j;
        aubio_scale_do(s->scaler, input);
        /* reset data */
        for (i=0; i < s->channels; i++)
                for (j=0; j < s->nelems; j++) 
                        s->hist[i][j] = 0;
        /* run accum */
        for (i=0; i < input->channels; i++)
                for (j=0;  j < input->length; j++) 
                                s->hist[i][(uint_t)floor(input->data[i][j])] += 1;
}

void aubio_hist_do_notnull (aubio_hist_t *s, fvec_t *input) 
{
        uint_t i,j;
        aubio_scale_do(s->scaler, input);
        /* reset data */
        for (i=0; i < s->channels; i++)
                for (j=0; j < s->nelems; j++) 
                        s->hist[i][j] = 0;
        /* run accum */
        for (i=0; i < input->channels; i++)
                for (j=0;  j < input->length; j++) 
                        if (input->data[i][j]!=0.0f) //input is not 0
                                s->hist[i][(uint_t)floor(input->data[i][j])] += 1;
}


void aubio_hist_dyn_notnull (aubio_hist_t *s, fvec_t *input) 
{
        uint_t i,j;
        smpl_t ilow = vec_min(input);
        smpl_t ihig = vec_max(input);
        smpl_t step = (ihig-ilow)/(smpl_t)(s->nelems);
        
        /* readapt */
        aubio_scale_set(s->scaler, ilow, ihig, 0, s->nelems);

        /* recalculate centers */
        s->cent[0] = ilow + 0.5f * step;
        for (i=1; i < s->nelems; i++)
                s->cent[i] = s->cent[0] + i * step;

        /* scale */     
        aubio_scale_do(s->scaler, input);

        /* reset data */
        for (i=0; i < s->channels; i++)
                for (j=0; j < s->nelems; j++) 
                        s->hist[i][j] = 0;
        /* run accum */
        for (i=0; i < input->channels; i++)
                for (j=0;  j < input->length; j++) 
                        if (input->data[i][j]!=0.) //input was not 0
                                s->hist[i][(uint_t)floorf(input->data[i][j])] += 1;
}

void aubio_hist_weigth (aubio_hist_t *s) 
{
        uint_t i,j;
        for (i=0; i < s->channels; i++)
                for (j=0; j < s->nelems; j++) {
                        s->hist[i][j] *= s->cent[j];
                }
}

smpl_t aubio_hist_mean (aubio_hist_t *s) 
{
        uint_t i,j;
        smpl_t tmp = 0.0f;
        for (i=0; i < s->channels; i++)
                for (j=0; j < s->nelems; j++)
                        tmp += s->hist[i][j];
        return tmp/(smpl_t)(s->nelems);
}