I recently discovered a web application that allows you to upload an image and it returns a palette of colors based on the colors in the original image. The idea behind this application is that designers are quickly given color codes that will compliment the image’s color scheme. The cartographic aspect that I discovered is that a mapmaker using an aerial or satellite image as their basemap can design their map so that the colors of subsequent layers correspond harmoniously. Simply take a portion of the basemap and upload it to the website and copy the output for future use.
Below are two more examples:
