2006.10.16 20:34 "[Tiff] Tag 346", by Ross Presser

2006.10.17 13:53 "Re: [Tiff] Tag 346", by Leonard Rosenthol

The data are not quite equivalent; the colors do have semantic meaning in this context -- it's important to know which pixels are magenta rather than black, and the magenta and black pixels are not shades of the same tint. It may work as an intermediate format. It would look rather odd on screen, though, as a grayscale image,

I didn't realize you were displaying on screen...

I thought you were just needing to process it for some particular purpose (scaling, etc.). In which case, it didn't matter what the color values were.

But yes, if you are actually planning to display it - and you know the colormap ahead of time - then sure, conversion of the indexed palette (ONLY) to RGB, performing the operations and then just replacing the palette back would be fine.

Leonard
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