GSoC CM collaboration

Kai-Uwe Behrmann ku.b at
Sun Mar 2 11:15:43 PST 2008

Am 02.03.08, 19:56 +0100 schrieb Maarten Maathuis:
> On 3/2/08, Kai-Uwe Behrmann <ku.b at> wrote:
> > Am 02.03.08, 19:14 +0100 schrieb Maarten Maathuis:

> >  > What kind of color correction do you have in mind? (besides the usual
> >  > gamma adjustment)
> >
> >
> > Many colour transformations are CLUT based. This is in case of X a
> >  3 dimensional table to interpolate from input to output. Additional
> >  gamma and matix operations can play a role. But for LCD's more and more
> >  CLUT's are used, as these devices are sometimes very non linear other than
> >  CRT's.
> If all you want is control of the LUT's, then i suggest you look at
> randrproto. I'm not sure if it's perfect yet, but it should be
> reasonable.
You talk about the graphics card gamma tables, while I talk about 3 
dimensional tables. Usually the a 3*3*17 sized for monitors and 
additional one dimensional curves. 
A 3*3*17 cube needs some interpolation routine to get the final 
output from an argitrary input. A nearest match would not suffice.

The graphics card gamma tables are one dimensional, containing usual 3*256 

kind regards
Kai-Uwe Behrmann
developing for colour management +

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