1. A method of tracking a road boundary, comprising: capturing a color image from a camera; identifying a pair of regions of interest (ROI) in the color image on each side of a candidate boundary position; extracting a color profile from each of the ROIs; generating a weighted color difference score by comparing the color profiles and weighting a difference between the color profiles based on a color similarity between colors in the color profiles; and outputting a determination of a first detected boundary based upon the weighted color difference score; and wherein the road boundary need not be painted to be detected.