A Novel Fuzzy Approach for Shape Determination of Traffic Signs

In this paper, a novel fuzzy approach is developed to determine the shape of traffic signs. More than 1600 images of traffic signs were collected in different light conditions by a digital camera mounted in a car and used for testing this approach. Every RGB image was converted into HSV colour space, and segmented by using a set of fuzzy rules depending on the hue and saturation values of each pixel in the HSV colour space. The fuzzy rules are used to extract the colours of the road signs. Objects in each segmented image are labelled and tested for the presence of probable sign. All small objects under certain threshold are discarded, and the remaining objects are tested by a fuzzy shape recognizer which invokes another set of fuzzy rules. Four shape measures are used to decide the shape of the sign; rectangularity, triangularity, ellipticity, and the new shape measure octagonality.