Using Gimp, I reduced an image to 4-colors indexed mode.
I actually need only 3 colors: black, blue and white/background, but due to the 2^n constraint I went for black, white and 2 shades of blue.
I did that in order to reduce file size as much as possible.
Now the question is what is the best lossless format to save this file in, that results in minimal file size?
Again - I'm using Gimp.
Especially, I'd be glad to find a file format that takes advantage of this reduced color depth. I assume that PNG and GIF, being general formats, do not take advantage of it. Am I wrong?