| 摘要 |
PURPOSE:To perform alignment of the image data of a small area positively even when the image data shows only edge in one direction or no pattern. CONSTITUTION:The image data to be inspected which is photographed by a photographing device 10 is differentiated and binarized by a first differentiating/ binarizing means 13. A reference image data is differentiated in a plurality of directions by a second differentiation/binarizing means 16, thereby detecting the differentiating direction showing the maximum differential value. Moreover, the reference image data is differentiated and binarized. A histogram in each differentiating direction is formed from the detected number of the maximum differentiating directions by a histrogram forming means 29, and an invalid differentiating direction is detected by an invalid direction detecting means 30. The image data to be inspected and the reference image data are processed through pattern-matching by correcting means 31, 32. The amount of the positional shift in the invalid direction detected at this time is invalidated. In consequence, the amount of the positional shift between the image data to be inspected and the reference image data is obtained. |
