Color Separation?

[Frankwpb1970]

(07-14-2022, 04:39 PM)rich2005 Wrote: Do you require a cmyk image file - a jpeg or a psd  There is a plugin called Cyan which is useful. there is an example here: https://www.gimp-forum.net/Thread-gimp-2...8#pid30238

Gimp is a RBG editor and all editing is RGB.
You can separate a rgb image into its c-m-y-k equivalent layers using Colors -> Components -> Decompose and choose CMYK {or RGB if that is what you want) from the drop down list.
That gives you greyscale images which are the masks of the separated colors.

It is a big subject and you should start with general concepts such as https://www.lifewire.com/color-separation-1697622
As you see, it is mostly a PhotoShop subject.

Edit: Just looking at your other posts: Is this for screen printing ? Some software mentioned here https://silverbobbin.com/color-separatio...-printing/

I can think of ways in Gimp but how many colors are you considering? Each color requires its own black & white mask.

Thanks for the reply, I would like to know both RGB and CMYK techniques. 
Im interested in making tshirts and want to use photo images to print on the shirts so if Im not doing black or white ink, I want to be abl to separate the colors and multicolor print.