[Openicc] Introduction / Gutenprint

[Stefan Döhla]

>    What I want to say is, the driver should support both, accept CMYK
>    and separate dark/light cyan and magenta internally in the driver,
>    or directly accept CcMmYK (6-color) from the caller.

I don't completely agree on this. The light inks do not really extend
the gamut but are intended to have better light tones. In more expensive
RIPs, you can set a threshold or mixture of the light and dark inks.

The initial calibration does usually look like this:
- set ink limits for the separate inks (because 80% is no more
  distinguishable from 100% of the)
- set thresholds, where the light ink replaces the default, dark one
- weight the inks to have maximum gamut and clear mixed colours
  (e.g. to have really red, not orange, when mixing M and Y)
- set a global maximum ink limit

This gives a proper setup to start regular linearization and profiling.
Printer manufacturers do the initial job for you (inside their drivers).

Stefan
-- 
Stefan Döhla
mailto:color at doehla.de