Re: [Openexr-devel] Introduction and CTL/ICC question

[Kai-Uwe Behrmann]

Am 10.03.05, 12:02 -0800 schrieb Joseph Goldstone:

> On Mar 10, 2005, at 11:35 AM, Kai-Uwe Behrmann wrote:
> 
> > Following Drew Hess mentioning:
> > > (except to say that there is a lot of work going on right now to
> > > figure out how to make ICC profiles work in a "digital cinema" world)
> > .. I asked if parameterized transforms will be the way within OpenEXR for
> > exchanging device characteristics.
> > 
> > Parameterized form makes me thinking about stuctures, logical
> > fillable by ICC profile structures and vice versa, Such as describing
> > colour primaries, matrices , gamma values, or using parametric curves as
> > described by section 6.5.14 of the ICC spec ...

> Were you serious about wanting a parameterized form for color primaries,
> matrices and gamma values, or was that rhetorical, with the real weight of
> your request concerning tone reproduction curves and the shaper LUTs expressed
> as a component of the lut16Type, lut8Type, lutAtoBType and lutBtoAType
> encodings?
 
My question included tone reproduction as well as profiles 
for content manipulation. While ICC CMMs usualy work with CLUTs or 
lattices (except display profiles), matrix based profiles often could very 
elegant express the same. Faced for instance with the imprecission 
of CLUT based profiles for large gamut differences, the matrix approach 
seems plausible.

regards
Kai-Uwe Behrmann
                                + development for color management 
                                + imaging / panoramas
                                + email: address@hidden
                                + http://www.behrmann.name