| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of accurately and stably detecting an edge position included in the picked-up gray-level image in one image processing without requiring a changeover processing in the case of sharp distribution of differential values near the edge part and even in the case of the displaced focal point and the gradual distribution of differential values near the edge. SOLUTION: In the method of detecting the edge position of a material to be measured from a gray-level image of the material to be measured picked up by a CCD camera, differential processing is performed to the gray-level image so as to form a differential image, and scanning is performed on this differential image, and the maximum value is extracted from among the differential values of the scanned picture elements, and symmetric computing is performed to the differential image near the peak position, a position of the picture element having the maximum differential value. A matching processing with the approximate curve is performed to the distribution curve obtained by the asymmetric computing so as to compute the edge position of the material to be measured. |
