Recognition of partial circular shapes from segmented contours

This paper presents a circle-finding method to deal with partially occluded circles using segmented contours. Contours are segmented using a criterion based on the derivative of the curvature. Constant curvature segments are primitives inputted into a clustering algorithm which brings out the relationships among contour segments which are likely to represent the same circles. A minimization criterion is used to find the circle parameters, providing an accurate parameter estimation. The method allows recovery of the contour segments used to estimate circle parameters, providing useful information in some practical applications. (C) 1996 Academic Press, Inc.