1. A computer-implemented method for characterizing colors of an image, wherein the image comprises a plurality of pixels, the method comprising: for each respective pixel of at least a subset of pixels of the image, assigning values to one or more color categories based on color information of the pixel; wherein, for each of one or more first pixels, said assigning comprises assigning values to a plurality of the color categories based on color information of the pixel; and determining information regarding the total values of pixels assigned to each of the color categories, wherein said information characterizes colors of the image: