Experimental Feature: Palette extraction from images

Experimental feature:
Extract palettes from images.

I haven't fully worked out a good way of simplifying palettes to remove very similar colors, but exact duplicates of colors will not be added. I'm currently trying to recursively compare colors using their Euclidean distance, removing those that are too similar. This does result in smaller palettes, but I still see many colors that are too similar to each other.

This works best with images that have no anti-aliasing and use a lossless format like png, tiff, or tga. The image in this post is a good example of what currently works well.

Large images with a lot of unique colors will be quite slow, the less colors in the image, the faster it will be to process.