FloatImg/funcs/geometry.c

/*
 *		FLOATIMG
 *	distorsions géométriques - coredumping ?
 */

#include  <stdio.h>
#include  <stdlib.h>

#include  "../floatimg.h"

/* --------------------------------------------------------------------- */
/*
 *	really crude function, need more work...
 */
int fimg_halfsize_0(FloatImg *src, FloatImg *dst, int notused)
{
int		wd, hd;
int		foo, x, y;
float		pixel[3];

#if DEBUG_LEVEL
fprintf(stderr, ">>> %s ( %p %p %d )\n", __func__,
			src, dst, notused);
#endif

			/* no magic check here ? */
if (dst->width || dst->height) {
	fprintf(stderr, "*** %s: image at %p not empty\n", __func__, dst);
	fimg_describe(dst, "destination halfsize 0");
	return -2;
	}

wd = src->width / 2;	hd = src->height / 2;
foo = fimg_create(dst, wd, hd, FIMG_TYPE_RGB);
if (foo) {
	fprintf(stderr, "%s: err create %d\n", __func__, foo);
	return -3;
	}

for (y=0; y<hd; y++) {
	for (x=0; x<wd; x++) {
		foo = fimg_get_rgb(src, x*2, y*2, pixel);
		if (foo) {
			fprintf(stderr, "%s: err get %d\n", __func__, foo);
			abort();
			}
		foo = fimg_plot_rgb(dst, x, y, pixel[0], pixel[1], pixel[2]);
		if (foo) {
			fprintf(stderr, "%s: err plot %d\n", __func__, foo);
			abort();
			}
		}

	}
return 0;
}
/* --------------------------------------------------------------------- */
int fimg_halfsize_1(FloatImg *src, FloatImg *dst, int notused)
{
int		wd, hd;
int		foo, x, y, x2, y2;
float		ac;

if (dst->width || dst->height) {
	fprintf(stderr, "*** %s: image at %p not empty\n", __func__, dst);
	fimg_describe(dst, "destination halfsize 1");
	return -2;
	}

wd = src->width / 2;	hd = src->height / 2;
if ( (foo = fimg_create(dst, wd, hd, FIMG_TYPE_RGB)) ) {
	fprintf(stderr, "%s: err create %d\n", __func__, foo);
	return -3;
	}

#define WS  (src->width)
#define WD  (dst->width)

for (y=0; y<hd; y++) {
	y2 = y * 2;
	for (x=0; x<wd; x++) {
		x2 = x * 2;

		ac = src->R[(y2*WS)+x2]      + src->R[(y2*WS)+x2+1] +
		     src->R[((1+y2)*WS)+x2]  + src->R[((1+y2)*WS)+x2+1];
		dst->R[y*WD +x] = ac / 4.0;

		ac = src->G[(y2*WS)+x2]      + src->G[(y2*WS)+x2+1] +
		     src->G[((1+y2)*WS)+x2]  + src->G[((1+y2)*WS)+x2+1];
		dst->G[y*WD +x] = ac / 4.0;

		ac = src->B[(y2*WS)+x2]      + src->B[(y2*WS)+x2+1] +
		     src->B[((1+y2)*WS)+x2]  + src->B[((1+y2)*WS)+x2+1];
		dst->B[y*WD +x] = ac / 4.0;

		}
	}

#undef WS
#undef WD

return 0;
}
/* --------------------------------------------------------------------- */