Interesting. I've had the idea for generating palettes based upon captured nature scenes or animals, especially birds and fish. Now that I think about it, take it a step further to include the habitat, and there you go: ecosystem palettes.
I wrote a simple web app to find the five most dominant colours in a photo, and present them as a bottom layer to the uploaded photo with the hexadecimal code included. So much used, at least by myself I love to see detected colours in all sorts of scenes or motives.
I used to Photoshop>Pixellate a nice photograph very coarsely, and cherry pick a few colours from the resulting "swatch". Not sure how sound a method it was, but it got me past analysis paralysis when starting a new project.
