FloatImg/lib/contrast.c

107 lines
1.8 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <math.h>
#include "../floatimg.h"
extern int verbosity;
/* ---------------------------------------------------------------- */
int fimg_square_root(FloatImg *s, FloatImg *d, double maxval)
{
int nbre, idx;
double dval;
if (s->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s : type %d invalide\n",
__func__, s->type);
return -4;
}
if (NULL==d) {
d = s;
}
nbre = s->width * s->height * 3;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * sqrt(dval);
}
return -1;
}
/* ---------------------------------------------------------------- */
int fimg_power_2(FloatImg *s, FloatImg *d, double maxval)
{
int nbre, idx;
double dval;
if (s->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s : src type %d invalide\n",
__func__, s->type);
return -4;
}
if (NULL==d) {
d = s;
}
else {
if (d->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s : dst type %d invalide\n",
__func__, s->type);
return -4;
}
}
nbre = s->width * s->height * 3;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * dval * dval;
}
return 0;
}
/* ---------------------------------------------------------------- */
/*
#macro Cos_01( X )
(0.5-0.5*cos( 3.141592654 * X))
#end
*/
int fimg_cos_01(FloatImg *s, FloatImg *d, double maxval)
{
int nbre, idx;
double dval;
if (s->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s : type %d invalide\n",
__func__, s->type);
return -4;
}
if (NULL==d) {
d = s;
}
nbre = s->width * s->height * 3;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * (0.5 - 0.5 * cos(3.141592654*dval));
}
return 0;
}
/* ---------------------------------------------------------------- */
/* ---------------------------------------------------------------- */