Road sign detection and recognition

Road sign detection is important to a robotic vehicle that automatically drives on roads. In this paper, road signs are detected by means of rules that restrict color and shape and require signs to appear only in limited regions in an image. They are then recognized using a template matching method and tracked through a sequence of images. The method is fast and can easily be modified to include new classes of signs. The road sign detection is used as part of a control system that autonomously drives a vehicle over paved roads. The primary application is to detect intersections, which are usually marked with street name signs or stop signs. An estimate of the range to the sign is computed based on the size of the sign and provides a cue to intersection detection software and driving control.