[Openicc] color-policy / RGB to CMYK

[Craig Bradney]

On Tuesday 01 March 2005 21:10, Leonard Rosenthol wrote:
> At 01:50 PM 3/1/2005, Jan-Peter Homann wrote:
> >If the free available SWOP-profile from Adobe is used as outputprofile in
> >Scribus, all RGB-gray or RGB-black is converted to CMYK-colors with each
> >channel containing some color. This happens because of the fixed
> >black-generation in an CMYK ICC-profile.
> >If the user wants RGB-gray or RGB-black only converted to the
> >black-channel of the CMYK-output, he needs a version of the SWOP-profile
> >with maximum GCR.
>
>          UNLESS the color managing software (Scribus in this case), is
> smart enough to special case R==G==B and handle it as a direct map to [0 0
> 0 1-R].  This is similar in concept to what the Windows PS driver or tools
> such as PDF Enhancer (http://www.pdfenhancer.com) do.
>
> >So the functionality of changing the black generation in an
> >ICC-CMYK-profile is something, which is useful for all softwares,
> >targeting the graphics arts market.
>
>          Yes, but it's also a complex operation that most users won't
> understand.  Most folks don't get color management as is - and adding
> something like Black Gen is just going to confuse them...
>
> >A second big market is e.g. producing CMYK-PDF from docbook-manuals.
> >In manuals, you have often a lot of screenshots. If Screenshots should be
> >printed in offset, RGB-black should stay pure CMYK-black.
>
>          See above ;).
>
>          But you are right, that is easier to solve on images via ICC since
> for images are you (hopefully) sending entire scanlines into the CMS.

RGB with profiling on export and printing is planned in our 1.3 dev series.

Craig
Scribus