libtthimage/Lib/dither2.c
2023-11-18 19:56:25 +01:00

191 lines
3.9 KiB
C

/*
dither2.c
---------
*/
#include <stdio.h>
#include <stdlib.h>
#include "../tthimage.h"
/*::------------------------------------------------------------------::*/
/* ya pas un probleme d'offset dans ces tables ? XXX */
static
int dx[]= { 0, 0, 0,
1, 1, 1,
2, 2, 2 };
static
int dy[]= { 0, 1, 2,
0, 1, 2,
0, 1, 2 };
/*::------------------------------------------------------------------::*/
/*
* I don't know how to do that ;) but I try hardly ;)
*/
int
Image_dither_3x3_0(Image_Desc *s, Image_Desc *d, int uh)
{
int x, y, r, g, b;
int foo, sr, sg, sb;
#if DEBUG_LEVEL
fprintf(stderr, "* %s le seuil est %d\n", __func__, uh);
#endif
if ( (foo=Image_compare_desc(s, d)) )
{
fprintf(stderr, "dither 3x3 0: images are differents %d\n", foo);
return foo;
}
#if DEBUG_LEVEL > 2
Image_TGA_save("/tmp/aaaa_debug_a.tga", s, 0);
#endif
/* XXX Image_clear(d, 0, 0, 0); */
for (y=0; y<s->height-3; y+=3)
{
for (x=0; x<s->width-3; x+=3)
{
/* compute the average of pixels in a 3x3 field */
sr = sg = sb = 0;
for (foo=0; foo<9; foo++)
{
sr += (s->Rpix[y+dy[foo]])[x+dx[foo]];
sg += (s->Gpix[y+dy[foo]])[x+dx[foo]];
sb += (s->Bpix[y+dy[foo]])[x+dx[foo]];
}
r = sr / 9;
g = sg / 9;
b = sb / 9;
/* plot all point, with colors based on average values */
(d->Rpix[y]) [x] = r<uh ? 0 : 255;
(d->Rpix[y+1]) [x] = r<uh ? 0 : 255;
(d->Rpix[y]) [x+1] = r<uh ? 0 : 255;
(d->Rpix[y+1]) [x+1] = r<uh ? 0 : 255;
(d->Gpix[y]) [x+1] = g<uh ? 0 : 255;
(d->Gpix[y+1]) [x+1] = g<uh ? 0 : 255;
(d->Gpix[y]) [x+2] = g<uh ? 0 : 255;
(d->Gpix[y+1]) [x+2] = g<uh ? 0 : 255;
(d->Bpix[y+1]) [x+1] = b<uh ? 0 : 255;
(d->Bpix[y+2]) [x] = b<uh ? 0 : 255;
(d->Bpix[y+2]) [x+2] = b<uh ? 0 : 255;
(d->Bpix[y+2]) [x+3] = b<uh ? 0 : 255;
}
}
#if DEBUG_LEVEL > 2
Image_TGA_save("/tmp/aaaa_debug_b.tga", d, 0);
#endif
return FUNC_IS_BETA;
}
/*::------------------------------------------------------------------::*/
/*
* 28 mars 2003...
*
* parameter 'uh' is not used.
*/
int
Image_dither_3x3_1(Image_Desc *s, Image_Desc *d, int uh)
{
int foo, x, y;
int sr, sg, sb;
if ( (foo=Image_compare_desc(s, d)) )
{
fprintf(stderr, "dither 3x3 1: images are differents %d\n", foo);
return foo;
}
#if DEBUG_LEVEL
fprintf(stderr, "* Image_dither_3x3_1 (%s) is experimental\n", __FILE__);
#endif
/* XXX Image_clear(d, 0, 0, 0); */
for (y=0; y<s->height-3; y+=3)
{
for (x=0; x<s->width-3; x+=3)
{
/* compute the average of pixels in a 3x3 field */
sr = sg = sb = 0;
for (foo=0; foo<9; foo++)
{
sr += (s->Rpix[y+dy[foo]])[x+dx[foo]];
sg += (s->Gpix[y+dy[foo]])[x+dx[foo]];
sb += (s->Bpix[y+dy[foo]])[x+dx[foo]];
}
for (foo=0; foo<sr/255; foo++)
{
if (foo>=9)
{
fprintf(stderr, "overflow\n");
return 666;
}
(d->Rpix[y+dy[foo]])[x+dx[foo]] = 255;
}
for (foo=0; foo<sg/255; foo++)
{
if (foo>=9)
{
fprintf(stderr, "overflow\n");
return 666;
}
(d->Gpix[y+dy[foo]])[x+dx[foo]] = 255;
}
for (foo=0; foo<sb/255; foo++)
{
if (foo>=9)
{
fprintf(stderr, "overflow\n");
return 666;
}
(d->Bpix[y+dy[foo]])[x+dx[foo]] = 255;
}
}
}
return FUNC_IS_BETA;
}
/*::------------------------------------------------------------------::*/
int
Image_dither_3x3_2(Image_Desc *s, Image_Desc *d, int uh)
{
int foo;
if ( (foo=Image_compare_desc(s, d)) )
{
fprintf(stderr, "dither 3x3 2: images are differents %d\n", foo);
return foo;
}
/* XXX Image_clear(d, 0, 0, 0); */
return FUNC_NOT_FINISH;
}
/*::------------------------------------------------------------------::*/
int
Image_dither_3x3_3(Image_Desc *s, Image_Desc *d, int uh)
{
int foo;
if ( (foo=Image_compare_desc(s, d)) )
{
fprintf(stderr, "dither 3x3 3: images are differents %d\n", foo);
return foo;
}
/* XXX Image_clear(d, 0, 0, 0); */
return FUNC_NOT_FINISH;
}
/*::------------------------------------------------------------------::*/