FloatImg/lib/contrast.c

188 lines
4.1 KiB
C

/*
* contrast.c - part of libfloatimg
* --------------------------------
*
* you can see some use in 'tools/fimgfx.c', so you can thing
* about the 'maxval' parameter. It was touchy :)
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <math.h>
#include "../floatimg.h"
extern int verbosity;
/* ---------------------------------------------------------------- */
int fimg_id_contraste(char *str)
{
if (!strcmp(str, "none")) return CONTRAST_NONE;
if (!strcmp(str, "sqrt")) return CONTRAST_SQRT;
if (!strcmp(str, "pow2")) return CONTRAST_POW2;
if (!strcmp(str, "cos01")) return CONTRAST_COS01;
if (!strcmp(str, "cos010")) return CONTRAST_COS010;
if (!strcmp(str, "xper")) return CONTRAST_XPER;
#if DEBUG_LEVEL
fprintf(stderr, "%s: unknow contrast name '%s'\n", __func__, str);
#endif
return -1;
}
/* ---------------------------------------------------------------- */
/*
* if the second parameter is NULL, operate 'in-place'
*/
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; }
else {
if (d->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s: dst type %d invalide\n",
__func__, d->type);
return -4;
}
}
nbre = s->width * s->height;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * sqrt(dval);
dval = s->G[idx] / maxval;
d->G[idx] = maxval * sqrt(dval);
dval = s->B[idx] / maxval;
d->B[idx] = maxval * sqrt(dval);
}
return 0;
}
/* ---------------------------------------------------------------- */
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__, d->type);
return -4;
}
}
nbre = s->width * s->height;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * dval * dval;
dval = s->G[idx] / maxval;
d->G[idx] = maxval * dval * dval;
dval = s->B[idx] / maxval;
d->B[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 DEBUG_LEVEL
fprintf(stderr, ">>> %s ( %p %p %g )\n", __func__, s, d, maxval);
#endif
if (s->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s: type %d invalide\n",
__func__, s->type);
return -4;
}
if (NULL==d) { d = s; } /* In place */
else {
if (d->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s: dst type %d invalide\n",
__func__, d->type);
return -4;
}
}
nbre = s->width * s->height;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * (0.5 - 0.5 * cos(3.141592654*dval));
dval = s->G[idx] / maxval;
d->G[idx] = maxval * (0.5 - 0.5 * cos(3.141592654*dval));
dval = s->B[idx] / maxval;
d->B[idx] = maxval * (0.5 - 0.5 * cos(3.141592654*dval));
}
return 0;
}
/* ---------------------------------------------------------------- */
int fimg_cos_010(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; }
else {
if (d->type != FIMG_TYPE_RGB) {
fprintf(stderr, "%s : dst type %d invalide\n",
__func__, d->type);
return -4;
}
}
nbre = s->width * s->height;
for (idx=0; idx<nbre; idx++) {
dval = s->R[idx] / maxval;
d->R[idx] = maxval * (0.5 - 0.5 * cos(2*3.141592654*dval));
dval = s->G[idx] / maxval;
d->G[idx] = maxval * (0.5 - 0.5 * cos(2*3.141592654*dval));
dval = s->B[idx] / maxval;
d->B[idx] = maxval * (0.5 - 0.5 * cos(2*3.141592654*dval));
}
return 0;
}
/* ---------------------------------------------------------------- */