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