Feature value selection manner, and its device for image recognition, stores the image analysis program the storage

摘要

PROBLEM TO BE SOLVED: To derive a stable characteristic value without being affected by the contour shape of a graphic form by dividing into a group of strongly curved parts and a group of weakly curved parts according to the value of the degree (sharp degree) of projecting and recessed parts on a contour and switching the definition of projecting and recessed directions (contour direction) to a different kind to perform calculation.;SOLUTION: This device traces continuous contours outside and inside a character image and produces a list of contour points for a traced contour. Next, it produces a list 331 of sharp degrees by deciding a value corresponding to the sharp angle of a curvature between the orientation before N contour points of each contour point and the orientation after N contour points from it. It is divided into five kinds being a strongly recessed part, a weakly recessed part, a linear/reverse point, a weakly projecting part and a strongly projecting part in accordance with a sharp degree. Then, when it is a strongly projecting part or a strongly recessed part, normal direction calculation is performed in contour direction deviation and when it is a linear/reverse point, tangential direction calculation is performed. Also, the middle point of a straight line connecting points being before N points and after N points is connected to an attentional contour point and calculation is performed with it as a contour direction.;COPYRIGHT: (C)2000,JPO