[Openicc] Named color profiles

[Richard Hughes]

I'm slightly confused about named color profiles. I've been asked to
support NCP in the gnome-color-manager viewer tool, but I'm a little
unsure of the basics.

As I understand it, each named color in a profile has a title (with
shared prefix and suffix) and two values, a PCS value and a device
value. I'm struggling to work out what the device value should be, if
the PCS is XYZ. Even if the PCS is Lab, surely for v4 profiles we
assume D50, and we can trivially work out the LAB value from the XYZ
value or vice versa. Basically I'm struggling to work out why you
would ever want a NCP with a PCS of Lab.

So a few questions:

* If the profile is v4 and PCS is XYZ, what values do I put into the
NC device? The same as the NC PCS?
* Do PCS Lab named color profiles exist? Does anybody have any
examples of NCPs of either PCS type?
* Is is possible to have a v2 NC profile with D65? Is it sane?
* What's the normal convention of displaying the
%{prefix}%{title}%{suffix} to the user as text? Delimit by " " or by "
- "

Thanks for any advice.

Richard.