In consideration of two features of traffic signs

colour and shape

a random sampling consensus（ RANSAC） which posses Harris angular point is proposed to detect traffic signs. The first phase is to conduct detection through Canny operator after colour extraction of the image. The second phase includes extracting initial image angular point with the help of Harris corner detector. The result is achieved by the matching between RANSAC algorithm and detection model. The simulation experiment shows that the 84 % of detection rate

basically meet the demand of instantaneity.