Sci. Form Vol. 3 (No. 2), pp. 87-101, 1988

Multi-Scale Curvatures—Multi-Resolutional Interpretation of Digital Curvatures for Contour Feature Extraction

Koichiro Deguchi

Department of Mathematical Engineering and Information Physics, Faculty of Engineering, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan

(Received August 12, 1988; Accepted November 3, 1988)

Keywords: Image Processing, Shape Representation, Contour Feature Analysis, Contour Curvature, Multi-Resolutional Interpretation

Abstract. This paper describes a new method of extracting figure's contour features based on its curvature. For a digital figure, curvatures are approximated by using differences of contour tangential angles at two points separated by an appropriate distance scale. In this method, a set of curvatures with various scales is calculated. From the curvature changes with respect to the multiple scales, the features of the original contour, such as the locations and angles of vertices, are extracted. In this method the "view-field resolutions" for the analysis of figure features are determined automatically, for each figure and its parts.