Representation of a curved boundary

A method of representing a boundary curve is presented. The proposed method first partitions a boundary into segments by curvature zero-crossings. Inflection points on the boundary are extracted as curvature zero-crossings using the convexity/concavity of points with respect to their neighbor points. Each segment is then approximated by a parametric cubic polynomial, and the boundary curve is represented by semantic and relational characteristics of these segments. The method generates a unique description for a boundary under rotation, translation, scale change, and even under slight deformation.<>