1993.12.08 21:25 "Re: CMYK Tiff Question", by Dan Seyb
Our new Scanner can only write CMYK Tiff files - BUT we need to have some RGB format.
I know it is only a (close) guess to convert from CMYK to RGB. Did someone out there ever write a little tool that would do the job. I have the libtiff (v3.3beta) but do not necessarily want to work my way into it as I'm more interested in the images.
Could someone help please...
The conversion simple enough i doubt anyone would bother unless it is part of a larger package. The Utah Raster Toolkit is the only place i can think to look for something like that.
The conversion is:
R = 1 - C
G = 1 - M
B = 1 - Y
if C == M == Y == 0,
R = G = B = 1 - K
The only place that might get tricky would be if the scanner
does undercolor removal (C, M, or Y != 0 and K != 0), and that
would be a smart scanner.
And a hint:
Track down Foley, van Dam, Feiner & Hughes "Computer Graphics, Principles and Practice, second edition", Addison-Wesley Publishing. It should be available at any decent technical/engineering bookstore. That is the bible.
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| dan seyb | Technical Software | |
| | Halliburton Energy Services | Internet : dseyb@halnet.com |
| | Houston, TX | Phone : (713) 496-8816 |
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