In this paper, a planar contour consisting of line segments and circular arcs is described in analytic form, and the contour matching problem is formulated as an optimization problem based on the criterion of minimax (or so-called minimal zone) errors. An iterative descent algorithm is developed to solve the multimodal and non-differentiable optimization problem, the solution of which reports the out-of-profile error and determines the scale and pose of the shape. (C) 1997 Elsevier Science B.V.