1. A method of estimating background color in an image comprising: providing a computing device to implement to following steps: accessing said image, wherein said image is comprised of a plurality of rows of pixels, each pixel having a color defined by a color vector comprised of multiple color values, each row of pixels within the image defining a scan line of the image; segmenting each scan line of the image into like-color line segments, wherein the colors of the pixels within each respective like-color line segment have a normal distribution about a mean color of the respective like-color line segment, and the standard deviation of the colors within each like-color line segment is smaller than a difference between its mean color and the mean color of its adjacent like-color line segment; grouping the like-color line segments by color; and estimating the background color on the basis of edge pixels along the line segments of said groups.