| 摘要 |
PURPOSE: To continuously detect picture edges by approximating actual gray level variation between each minimum and adjacent maximum at an image matrix, which is not filtered by a prescribed function with an inflection point, and making the position of the inflection point express the point of a searched edge. CONSTITUTION: A video edge detector is provided with an image pickup device 10, memories 12, 16, 20 and 24, a processor 14, an external value device 18 and an approximate unit 22. By the image matrix filtered here, the local minimum and maximum of the gray level are decided and separately stored in four directions extended mutually at 45 deg.. After deciding all the maximums and minimums in the filtered image matrix, actual gray level variation in a related direction is approximated between each minimum and adjacent maximum in an image matrix which is not filtered by a prescribed function with the inflection point and the position of the inflection point expresses the point of a searched edge. Thereby the edge which is not intermittent but continuous in all cases is detected. |
