/Avc/paint_2.js

http://github.com/mbebenita/Broadway · JavaScript · 35 lines · 32 code · 3 blank · 0 comment · 2 complexity · db035fd75c5ac3b29fc6f35feedb884c MD5 · raw file 

    

  1. function _paint($luma, $cb, $cr, w, h) {
    2. 

  2.   for (var y1,y2,u,v,ruv,guv,buv,j,w_2=w>>1,W=w*4, surface=SDL.surfaces[SDL.screen], d=surface.image.data, r=0; h-=2;) {
    3. 

  3.     for (j=w_2; j--;) {
    4. 

  4.       u = HEAPU8[$cr++];
    5. 

  5.       v = HEAPU8[$cb++];
    6. 

  6.       ruv = 409*u-56992;
    7. 

  7.       guv = 34784-208*u-100*v;
    8. 

  8.       buv = 516*v-70688;
    9. 

  9. 

  10.       y2 = HEAPU8[$luma+w]*298;
    11. 

  11.       y1 = HEAPU8[$luma++]*298;
    12. 

  12.       d[r+W] = y2+ruv>>8;
    13. 

  13.       d[r++] = y1+ruv>>8;
    14. 

  14.       d[r+W] = y2+guv>>8;
    15. 

  15.       d[r++] = y1+guv>>8;
    16. 

  16.       d[r+W] = y2+buv>>8;
    17. 

  17.       d[r++] = y1+buv>>8;
    18. 

  18.       r++;
    19. 

  19. 

  20.       y2 = HEAPU8[$luma+w]*298;
    21. 

  21.       y1 = HEAPU8[$luma++]*298;
    22. 

  22.       d[r+W] = y2+ruv>>8;
    23. 

  23.       d[r++] = y1+ruv>>8;
    24. 

  24.       d[r+W] = y2+guv>>8;
    25. 

  25.       d[r++] = y1+guv>>8;
    26. 

  26.       d[r+W] = y2+buv>>8;
    27. 

  27.       d[r++] = y1+buv>>8;
    28. 

  28.       r++;
    29. 

  29.     }
    30. 

  30.     r+=W;
    31. 

  31.     $luma+=w;
    32. 

  32.   }
    33. 

  33.   surface.ctx.putImageData(surface.image, 0, 0 );
    34. 

  34. }
    35.