Color masking in GIMP


I was wondering if there is a way in GIMP to create a color mask using RGB values instead of the Select by Color tool?

Thanks for the input.


I can not work out anyway to do an rgb selection in GIMP. Playing with the select by color tool and adjusting the threshold values is the closest method I could come up with. However, in darktable you can create parametric masks based on many values including hue or color. The best masking system I have come across.

Why do you need a mask based upon color? I ask this to fully understand the problem and how it may be resolved.

Hi Terry:

Thanks for getting back to me. Iā€™m a graphic designer. In my work, I blend images into solid color backgrounds. I have used Corel Photopaint for years. The color masking feature allow me to quickly select a blended image using RGB. In GIMP I use the eyedropper to identify the pixel color, set a vertical and horizontal guide to mark that pixels location, and then use the Select by Color tool to click in that precise location to get the mask I need. The methodology works fine, but its just slower than the RGB method in Corel.

The reason I started to familiarize with GIMP is because it is a robust, free program. The people who view my artwork need a photo manipulation program to decipher my work. If they do not have such a program I recommend they use GIMP. I include instructions with my pieces based on using GIMP. It just takes a little longer to instruct a user how to create the needed mask if no RGB select method is available. I just wanted to keep it as simple as possible.

No worries. I just thought I might have overlooked an RGB selection methodology in GIMP. You can more fully understand my use of masks in you visit my website at

Thanks again for your input.


Hi @tigerstime, and welcome!

Have fun!
Claes in Lund, Sweden

Try the ofn-color-select script.

Installation instructions at the bottom of the linked page. HTML doc in the ZIP.

Bytes are still wet, so use with care.

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