[cairo] Spot colors (and CMYK)

James Cloos cloos at jhcloos.com
Wed Jan 20 16:17:08 PST 2010


>>>>> "Bill" == Bill Spitzak <spitzak at gmail.com> writes:

Bill> I do not understand. What exactly do you think EVERY SINGLE PROGRAM IN 
Bill> THE WORLD does with those current CMYK "alternatives" when they draw 
Bill> them on the screen?

Bill> I find it impossible to believe that any program does anything other 
Bill> than the simplistic conversion. Any "smarter" program will instead use 
Bill> the pantone color directly.

Look at the XPDF or poppler src.  They follow adobe's lead in converting
DeviceCMYK to DeviceRGB (aka sRGB).  The transform is straight forward,
not too complex, but is not at all a simple r=m-1 kind of transform.

Also, look for:

/usr/share/ghostscript/${VERSION}/Resource/ColorSpace/DefaultCMYK

and compare that against the TrivialCMYK in the same dir.  That does the
same transform.

The idea is to simulate the look of a typical office colour laser
printing to typical office uncoated paper on an sRGB monitor when
each is viewed in conditions.

-JimC
-- 
James Cloos <cloos at jhcloos.com>         OpenPGP: 1024D/ED7DAEA6


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