System and method for identifying scale invariant features of object outlines on images

摘要

The present invention relates to a system and method for identifying scale invariant features of image outlines. The method comprises the steps of; receiving a parametric equation of a closed planar curve; choosing nodes on the closed planar curve with equal intervals; generating a continuous scale space of the nodes on the curve; calculating circle of curvature for every node on the closed curve for every scale in every octave; finding circle of curvature differences between plurality of adjacent scales; comparing each curvature difference value and choosing the nodes with a minimum or maximum curvature difference as feature points; representing the outline with a descriptor including all the feature points. The method further comprises the steps; eliminating the feature points which are closer to each other than a predetermined threshold; and comparing a descriptor with each previously recorded descriptor belonging to various outlines, finding at least one descriptor with a good match.