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Deciphering mask data.

Open therahedwig opened this issue 6 years ago • 1 comments

Ok, so I've gotten pretty far with deciphering transparency mask data:

  1. Masks are stored as 16bit, not 8bit like the color raster data.
  2. The highest value of a given mask seems to be 16447???

This isn't as important as getting big raster data to load, but I am terribly confused why the maximum value is 16447...

therahedwig avatar Sep 12 '19 16:09 therahedwig

16447 has a bit pattern 0100000000111111 which might imply some kind of alternate encoding is going on such as fixed point or some other type of packed binary format or something. The last 6 bits probably actually encodes the pixel intensity.

Wunkolo avatar Sep 12 '19 17:09 Wunkolo