You should try : http://gmic.sourceforge.net/gimp.shtml
I make a screenshot for you here :
you can try LAB Curves for GIMP : http://www.mm-log.com/lab-curves-gimp
Sourceforge here : http://sourceforge.net/projects/mmfilters/files/
> sorry it is a german text, but looking at the pictures might
> say enough:
> Theese feature of changing color tones is, what I'm looking for
> since a while.
> It's necessary to have Lab-mode, which seems to be nonsense
> to some developers, but the results show me: it makes sense
> to use that mode.
> Maybe not as underlying representation, but available to users
> it should be.
> Maybe a conversion filter that makes RGB->Lab and Lab->RGB,
> available for users (and their scripts) would be helpful.
> Gimp-developer mailing list
Nemes Ioan Sorin
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