sys/src/cmd/jpg/close.c

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