1. A method of dividing a digital image into segments, wherein the digital image comprises an array of pixels each having a pixel location and a pixel color value, the method comprising: obtaining an image frame comprising an array of pixels each having a pixel color value; assigning an initial segment identifier to each pixel in the image frame independent of each pixel's pixel color value; testing, using an appropriateness test, pixels for possible reassignment from a current segment to a neighboring segment; and if the appropriateness test indicates a pixel should be reassigned, reassigning the segment identifier of the pixel.