| 摘要 |
PURPOSE: To accurately inspect an objective picture pattern in comparison with reference by averaging in a vertical direction a picture that a picture pattern is picked up, removing noises therefrom, processing it differentially in a vertical direction to emphasize edges thereof, detecting program searching marks from a plurality of edges and positioning the picture pattern. CONSTITUTION: A picture pattern to be inspected is picked up as a picture expanding in vertical and horizontal directions by a CCD camera, etc., and the picture data of respective picture elements is measured. Next, the picture is averaged in a vertical direction to remove the picture noises. Then, the picture data is subject to differential processing in a vertical direction, and only the maximum value of density in a differential value is extracted, then all excluding a vertex part of the density are erased. Further, an edge of specified density or more is extracted in a vertical direction and edges near other edges along the vertical direction are removed. After such operations, a horizontal edge that lasts a specified width in a horizontal direction is selected among them, and one of the maximum density is set as a program searching mark. Based on the result, a picture pattern is positioned and is further compared with a reference picture pattern. |
