I am interested. I am new ti GIMP development, which I do in my spare time. I am starting to modify the newsprint CMYK mode to directly separate into CMYK layers instead of a flat image as it is now. The CMYK decompose function appears to be broken in my version of 2.10, four black layers appear. I will look into that also. Cheers, and let me know what I can help with. Octavio On Sat, May 18, 2019 at 9:28 PM Øyvind Kolås <pippin@xxxxxxxx> wrote: > On Sat, May 18, 2019 at 10:33 PM Eleftheria Chatziargyriou via > gimp-developer-list <gimp-developer-list@xxxxxxxxx> wrote: > > Hello everyone, > > > > I am occasionally developing a colour theory library as a pet project and > > oftentimes compare it against widely established tools. I was quite > > surprised to see that GIMP doesn't offer any support for the CMYK mode. > > > > I did a bit of searching around and it seems that the feature was popular > > enough to warrant a plug-in (Separate+) which now seems deprecated. > Beyond > > that, I also found a few scattered threads requesting this feature most > of > > which where redirected to the aforementioned plug-in. > > > > Is there any interest for seeing CMYK support as a part of gimp, or is it > > beyond the scope of the project? > > It is very much in scope, and some of the internals are already ready. > The underlying core GIMP imaging libraries babl and GEGL provide > GIMP-2.10 with high-bit depth support. GEGL supports full internal > color management and mixing of image buffers in grayscale, RGB, CMYK, > CIE Lab color spaces of various bit depths and other aspects of pixel > format encoding. For tasks as image loading/saving from JPG/TIFF, > scaling, rotating, cropping, blurring, text-rendering, basic > compositing and more GEGL already handles CMYK. > > Work is underway in GIMP's master branch completing refactorings that > add the previous big feature improvement of babl. The extension of the > pixelformat from keeping track of different encodings of possibly > unbounded sRGB based pixel formats to include color space information > as contained in RGB Matrix ICC profiles. That work which among GIMP > developers is known as the space invasion, since it adds better > support for color-spaces and it adds a space argument to many > functions also lays the foundation for later starting to add support > in GIMP for CMYK as a mode on par with RGB, Grayscale and Indexed. > > Even after that is in place, for *photos* I would strongly urge to > work in RGB and use modern workflows with late-binding, totally > avoiding the new CMYK mode, there is other graphic design use-cases - > with vectors, text and more where it will be more useful; but not for > basic things like retouching and color and light adjustment in > photograhps. When constraints of other tools or workflow demands CMYK > TIFF or JPGs, conversion should happen at export time similar to what > separate+ provides, and the CMYK support would be limited to soft > proofing with the CMYK gamut. > > /pippin - https://pippin.gimp.org/ > _______________________________________________ > gimp-developer-list mailing list > List address: gimp-developer-list@xxxxxxxxx > List membership: > https://mail.gnome.org/mailman/listinfo/gimp-developer-list > List archives: https://mail.gnome.org/archives/gimp-developer-list > _______________________________________________ gimp-developer-list mailing list List address: gimp-developer-list@xxxxxxxxx List membership: https://mail.gnome.org/mailman/listinfo/gimp-developer-list List archives: https://mail.gnome.org/archives/gimp-developer-list
