| 摘要 |
PURPOSE:To prevent a meaningless straight line from being detected, by deciding a dark/bright boundary or a bright/dark boundary by a direction of a density gradient vector and a detecting position, and adding, subtracting and accumulating a group to plural picture elements in a prescribed area of an original image in accordance with each picture element based on said result. CONSTITUTION:A density gradient of an original image is detected by a density gradient detecting mechanism 1, and based thereon, a direction of a density gradient vector and a detecting position are derived by an angle distance calculating mechanism 2, and from a relation of both of them, whether an edge is a dark/bright boundary or a bright/dark boundary is discriminated by a bright/dark deciding mechanism 3, and it is mapped to the same point by plus accumulation or minus accumulation by a HUFF conversion positive/negative cumulative storage device 4, therefore, by the storage capacity of half of a conventional device, the same effect is obtained. Also, at the time of search of the same storage area, bright dark/dark bright can be fetched separately or simultaneously. Moreover, a meaningless border line in which dark bright/bright dark is mixed in confusion comes to be scarcely detected. |
