[Openicc] Re: Hello *and* (was): LINUX, Gutenprint / CUPS / Color policies

[Chris Murphy]

On May 12, 2005, at 7:11 PM, Robert L Krawitz wrote:

>    From: Chris Murphy <lists at colorremedies.com>
>
>    A driver ensuring conversion from pixels to commands to produce
>    droplets in a reasonably consistent, predictable and logical manner
>    is fundamental. Colorimetric accuracy is not.
>
>
> There's more to it than that -- if the input is RGB, black generation
> needs to be done in a reasonable way, and presumably you want good
> linearization, and generation of extra inks if needed.  Things like
> that are exactly what we have to figure out.

I put black generation, linearization, etc. under the "logical" 
category. :) There does need to be an attempt at making the tone 
response of the output device mimic the tone response of the source 
file (or do a better job than the original file), and some basic color 
coordination is necessary so that "red" prints "red" and not "pink" or 
"orange". Colorimetric accuracy is, to me, not a fundamental 
requirement of printer drivers. It's a desired feature for certain 
market segments. The average consumer that owns an inkjet printer, is 
not using ICC profiles let alone custom ones, and yet they manage to 
get quite acceptable output. It's the difference between accurate 
color, and pleasing color.

>
>    No print drivers from the major manufacturers perform color
>    management with a particular print job containing multiple source
>    profiles. On both platforms, this is deferred to the operating 
> system
>    to manage with input from the printer driver based on print dialog
>    settings.
>
> I wasn't aware that either Linux or BSD did any color management in
> the OS :-)

*sigh* yes of course. When using my professional hat, thus far I 
haven't come into contact with an OS other than Windows or Mac OS in a 
color management context. So, my writing sometimes reveals my 
occupationally induced myopic world view of available operating 
systems.

> Again, remember that there's at least one driver developer on this
> list (me), and hopefully there are folks from the other major free
> source printer driver projects (HPIJS, Omni) here too.

I realize that. I'm admittedly extrapolating from my experiences here, 
since I have very little with other OS's, especially in a color 
management context. But the OS-specific anecdote is merely to point out 
that making drivers complicated without a really good reason isn't a 
good idea. I'd need to hear some compelling reasons for making print 
drivers themselves the center of the CMS when it comes to arbitrating 
whether to convert or not.


Chris Murphy
Color Remedies (TM)
www.colorremedies.com/realworldcolor
---------------------------------------------------------
Co-author "Real World Color Management, 2nd Ed"
Published by PeachPit Press (ISBN 0-321-26722-2)
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