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#include <u.h>
#include <libc.h>
#include <draw.h>
float c1 = 1.402;
float c2 = 0.34414;
float c3 = 0.71414;
float c4 = 1.772;
int
closest(int Y, int Cb, int Cr)
{
double r, g, b;
double diff, min;
int rgb, R, G, B, v, i;
int y1, cb1, cr1;
Cb -= 128;
Cr -= 128;
r = Y+c1*Cr;
g = Y-c2*Cb-c3*Cr;
b = Y+c4*Cb;
/*print("YCbCr: %d %d %d, RGB: %g %g %g\n", Y, Cb, Cr, r, g, b); */
min = 1000000.;
v = 1000;
for(i=0; i<256; i++){
rgb = cmap2rgb(i);
R = (rgb >> 16) & 0xFF;
G = (rgb >> 8) & 0xFF;
B = (rgb >> 0) & 0xFF;
diff = (R-r)*(R-r) + (G-g)*(G-g) + (B-b)*(B-b);
/* y1 = 0.5870*G + 0.114*B + 0.299*R; */
/* cb1 = (B-y1)/1.772; */
/* cr1 = (R-y1)/1.402; */
if(diff < min){
/* if(Y==0 && y1!=0) */
/* continue; */
/* if(Y==256-16 && y1<256-16) */
/* continue; */
/* if(Cb==0 && cb1!=0) */
/* continue; */
/* if(Cb==256-16 && cb1<256-16) */
/* continue; */
/* if(Cr==0 && cr1!=0) */
/* continue; */
/* if(Cr==256-16 && cr1<256-16) */
/* continue; */
/*print("%d %d %d\n", R, G, B); */
min = diff;
v = i;
}
}
if(v > 255)
abort();
return v;
}
#define SHIFT 5
#define INC (1<<SHIFT)
typedef struct Color Color;
struct Color
{
int col;
Color *next;
};
Color *col[INC*INC*INC];
void
add(int c, int y, int cb, int cr)
{
Color *cp;
y >>= 8-SHIFT;
cb >>= 8-SHIFT;
cr >>= 8-SHIFT;
cp = col[cr+INC*(cb+INC*y)];
while(cp != nil){
if(cp->col == c)
return;
cp = cp->next;
}
cp = malloc(sizeof(Color));
cp->col = c;
cp->next = col[cr+INC*(cb+INC*y)];
col[cr+INC*(cb+INC*y)] = cp;
}
void
main(void)
{
int y, cb, cr, n;
Color *cp;
for(y=0; y<256; y++){
for(cb=0; cb<256; cb++)
for(cr=0;cr<256;cr++)
add(closest(y, cb, cr), y, cb, cr);
fprint(2, "%d done\n", y);
}
for(y=0; y<INC*INC*INC; y++){
n = 0;
cp = col[y];
while(cp != nil){
n++;
cp = cp->next;
}
cp = col[y];
while(cp != nil){
n++;
print("%d ", cp->col);
cp = cp->next;
}
print("\n");
}
}
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