How to separate an image into multiple layers based on color

[tmanni]

One precision about the Posterize filter:
The parameter "Posterize levels" does not control the number of intensities the final image will have.
It determines how many intervals are used to split the whole range of intensities.
So if no pixels fall into one or more intervals, you will have less intensities in the final result than the level number.

[Ofnuts]

(04-29-2020, 09:04 AM)tmanni Wrote: One precision about the Posterize filter:
The parameter "Posterize levels" does not control the number of intensities the final image will have.
It determines how many intervals are used to split the whole range of intensities.
So if no pixels fall into one or more intervals, you will have less intensities in the final result than the level number.

And this seems to be the number of intensities per channel, so if you have 3 levels, you have potentially 3**3 colors in the output.