PURPOSE: To enable judgement independent of the position deviation and rotation at a high speed by taking the contour shape of the specified model as the reference shape and positioning based on the partial shape.

CONSTITUTION: Estimation areas B-D to be estimated are specified as a quadrilateral area having proper areas. The postioning between the reference shape and input shape is performed. The dot-array on the input shape included in the estimated areas B-D on the reference shape is made the object to estimate the shape evaluation. The positioning based on the partial shape is performed by searching the combination of points which minimizes information of reference parts a-c specified in advance in the reference shape A stored in a picture processor computer and an evaluation function (f) to be decided by the information of a point of an input shape B which is newly inputted from the input shape from the input shape. The parameters , u, and v of the coordinate conversion where the searched point and the point on the reference shape are overlapped are decided. By converting the coordinates of the input data, the partial shape of both are matched.