1 28994509 2004-04-21 devnull #include <u.h>
  2 28994509 2004-04-21 devnull #include <libc.h>
  3 28994509 2004-04-21 devnull #include <draw.h>
  4 28994509 2004-04-21 devnull 
  5 28994509 2004-04-21 devnull float c1 = 1.402;
  6 28994509 2004-04-21 devnull float c2 = 0.34414;
  7 28994509 2004-04-21 devnull float c3 = 0.71414;
  8 28994509 2004-04-21 devnull float c4 = 1.772;
  9 28994509 2004-04-21 devnull 
 10 28994509 2004-04-21 devnull 
 11 28994509 2004-04-21 devnull int
 12 28994509 2004-04-21 devnull closest(int Y, int Cb, int Cr)
 13 28994509 2004-04-21 devnull {
 14 28994509 2004-04-21 devnull 	double r, g, b;
 15 28994509 2004-04-21 devnull 	double diff, min;
 16 28994509 2004-04-21 devnull 	int rgb, R, G, B, v, i;
 17 28994509 2004-04-21 devnull 	int y1, cb1, cr1;
 18 28994509 2004-04-21 devnull 
 19 28994509 2004-04-21 devnull 	Cb -= 128;
 20 28994509 2004-04-21 devnull 	Cr -= 128;
 21 28994509 2004-04-21 devnull 	r = Y+c1*Cr;
 22 28994509 2004-04-21 devnull 	g = Y-c2*Cb-c3*Cr;
 23 28994509 2004-04-21 devnull 	b = Y+c4*Cb;
 24 28994509 2004-04-21 devnull 
 25 cbeb0b26 2006-04-01 devnull /*print("YCbCr: %d %d %d, RGB: %g %g %g\n", Y, Cb, Cr, r, g, b); */
 26 28994509 2004-04-21 devnull 
 27 28994509 2004-04-21 devnull 	min = 1000000.;
 28 28994509 2004-04-21 devnull 	v = 1000;
 29 28994509 2004-04-21 devnull 	for(i=0; i<256; i++){
 30 28994509 2004-04-21 devnull 		rgb =  cmap2rgb(i);
 31 28994509 2004-04-21 devnull 		R = (rgb >> 16) & 0xFF;
 32 28994509 2004-04-21 devnull 		G = (rgb >> 8) & 0xFF;
 33 28994509 2004-04-21 devnull 		B = (rgb >> 0) & 0xFF;
 34 28994509 2004-04-21 devnull 		diff = (R-r)*(R-r) + (G-g)*(G-g) + (B-b)*(B-b);
 35 cbeb0b26 2006-04-01 devnull /*		y1 = 0.5870*G + 0.114*B + 0.299*R; */
 36 cbeb0b26 2006-04-01 devnull /*		cb1 = (B-y1)/1.772; */
 37 cbeb0b26 2006-04-01 devnull /*		cr1 = (R-y1)/1.402; */
 38 28994509 2004-04-21 devnull 		if(diff < min){
 39 cbeb0b26 2006-04-01 devnull /*			if(Y==0 && y1!=0) */
 40 cbeb0b26 2006-04-01 devnull /*				continue; */
 41 cbeb0b26 2006-04-01 devnull /*			if(Y==256-16 && y1<256-16) */
 42 cbeb0b26 2006-04-01 devnull /*				continue; */
 43 cbeb0b26 2006-04-01 devnull /*			if(Cb==0 && cb1!=0) */
 44 cbeb0b26 2006-04-01 devnull /*				continue; */
 45 cbeb0b26 2006-04-01 devnull /*			if(Cb==256-16 && cb1<256-16) */
 46 cbeb0b26 2006-04-01 devnull /*				continue; */
 47 cbeb0b26 2006-04-01 devnull /*			if(Cr==0 && cr1!=0) */
 48 cbeb0b26 2006-04-01 devnull /*				continue; */
 49 cbeb0b26 2006-04-01 devnull /*			if(Cr==256-16 && cr1<256-16) */
 50 cbeb0b26 2006-04-01 devnull /*				continue; */
 51 cbeb0b26 2006-04-01 devnull /*print("%d %d %d\n", R, G, B); */
 52 28994509 2004-04-21 devnull 			min = diff;
 53 28994509 2004-04-21 devnull 			v = i;
 54 28994509 2004-04-21 devnull 		}
 55 28994509 2004-04-21 devnull 	}
 56 28994509 2004-04-21 devnull 	if(v > 255)
 57 28994509 2004-04-21 devnull 		abort();
 58 28994509 2004-04-21 devnull 	return v;
 59 28994509 2004-04-21 devnull }
 60 28994509 2004-04-21 devnull 
 61 28994509 2004-04-21 devnull #define 	SHIFT	5
 62 28994509 2004-04-21 devnull #define	INC		(1<<SHIFT)
 63 28994509 2004-04-21 devnull 
 64 28994509 2004-04-21 devnull typedef struct Color Color;
 65 28994509 2004-04-21 devnull 
 66 28994509 2004-04-21 devnull struct Color
 67 28994509 2004-04-21 devnull {
 68 28994509 2004-04-21 devnull 	int		col;
 69 28994509 2004-04-21 devnull 	Color	*next;
 70 28994509 2004-04-21 devnull };
 71 28994509 2004-04-21 devnull 
 72 28994509 2004-04-21 devnull Color	*col[INC*INC*INC];
 73 28994509 2004-04-21 devnull 
 74 28994509 2004-04-21 devnull void
 75 28994509 2004-04-21 devnull add(int c, int y, int cb, int cr)
 76 28994509 2004-04-21 devnull {
 77 28994509 2004-04-21 devnull 	Color *cp;
 78 28994509 2004-04-21 devnull 
 79 28994509 2004-04-21 devnull 	y >>= 8-SHIFT;
 80 28994509 2004-04-21 devnull 	cb >>= 8-SHIFT;
 81 28994509 2004-04-21 devnull 	cr >>= 8-SHIFT;
 82 28994509 2004-04-21 devnull 	cp = col[cr+INC*(cb+INC*y)];
 83 28994509 2004-04-21 devnull 	while(cp != nil){
 84 28994509 2004-04-21 devnull 		if(cp->col == c)
 85 28994509 2004-04-21 devnull 			return;
 86 28994509 2004-04-21 devnull 		cp = cp->next;
 87 28994509 2004-04-21 devnull 	}
 88 28994509 2004-04-21 devnull 	cp = malloc(sizeof(Color));
 89 28994509 2004-04-21 devnull 	cp->col = c;
 90 28994509 2004-04-21 devnull 	cp->next = col[cr+INC*(cb+INC*y)];
 91 28994509 2004-04-21 devnull 	col[cr+INC*(cb+INC*y)] = cp;
 92 28994509 2004-04-21 devnull }
 93 28994509 2004-04-21 devnull 
 94 28994509 2004-04-21 devnull void
 95 28994509 2004-04-21 devnull main(void)
 96 28994509 2004-04-21 devnull {
 97 28994509 2004-04-21 devnull 	int y, cb, cr, n;
 98 28994509 2004-04-21 devnull 	Color *cp;
 99 28994509 2004-04-21 devnull 
100 28994509 2004-04-21 devnull 	for(y=0; y<256; y++){
101 28994509 2004-04-21 devnull 		for(cb=0; cb<256; cb++)
102 28994509 2004-04-21 devnull 			for(cr=0;cr<256;cr++)
103 28994509 2004-04-21 devnull 				add(closest(y, cb, cr), y, cb, cr);
104 28994509 2004-04-21 devnull 		fprint(2, "%d done\n", y);
105 28994509 2004-04-21 devnull 	}
106 28994509 2004-04-21 devnull 	for(y=0; y<INC*INC*INC; y++){
107 28994509 2004-04-21 devnull 		n = 0;
108 28994509 2004-04-21 devnull 		cp = col[y];
109 28994509 2004-04-21 devnull 		while(cp != nil){
110 28994509 2004-04-21 devnull 			n++;
111 28994509 2004-04-21 devnull 			cp = cp->next;
112 28994509 2004-04-21 devnull 		}
113 28994509 2004-04-21 devnull 		cp = col[y];
114 28994509 2004-04-21 devnull 		while(cp != nil){
115 28994509 2004-04-21 devnull 			n++;
116 28994509 2004-04-21 devnull 			print("%d ", cp->col);
117 28994509 2004-04-21 devnull 			cp = cp->next;
118 28994509 2004-04-21 devnull 		}
119 28994509 2004-04-21 devnull 		print("\n");
120 28994509 2004-04-21 devnull 	}
121 28994509 2004-04-21 devnull }