Best way to select area bounded by a specific colored line

[Krikor]

(04-20-2024, 09:10 PM)T-buch Wrote: If I want to select an area which is bounded by a specific colored line (se the attached sample) how can I do that the easiest and with the greatest possible accuracy?

With Select by Color (Shift+o) you select the line that outlines the colors.
With the selection active you can paint this selection with the color of your choice. (here I used black color).
This way you have obtained the desired area.

   

If you want, just select each transparent area and add colors individually to each one.