anchor.diff:          }
           break;
         case Format.bgr:
  -        for (var i = 0, j = 0, len = input.length; i < len; i += 4, j += 3) {
  +        for (var i = 0, j = 0, len = input.length; j < len; i += 4, j += 3) {
             rgba[i + 0] = input[j + 2];
             rgba[i + 1] = input[j + 1];
             rgba[i + 2] = input[j + 0];
  
positive.code:         }
          break;
        case Format.luminance:
          for (var i = 0, j = 0, len = input.length; i < len; i += 4, ++j) {
            rgba[i + 0] = input[j];
            rgba[i + 1] = input[j];
            rgba[i + 2] = input[j];
  
negative.code:         }
          break;
        case Format.rgb:
          for (var i = 0, j = 0, len = input.length; j < len; i += 4, j += 3) {
            rgba[i + 0] = input[j + 0];
            rgba[i + 1] = input[j + 1];
            rgba[i + 2] = input[j + 2];
  