| 摘要 |
PURPOSE:To allow highly accurate high speed detection of contamination around a seam by generating a subwindow of predetermined profile having center at a predetermined point on the extension of the seam thereby detecting black contamination in the vicinity of upper seam. CONSTITUTION:After a seam line L is determined by a seam line position determining circuit, coordinates of intersection P of the line L and a ring window 30 are calculated. A predetermined offset amount 44 is then added to the coordinates of the intersection P thus determining a point O'. A window region for an object to be inspected is then determined with a circle of predetermined radius (r) having center at the point O' as a subwindow 41. A rectangular region S circumscribing the subwindow 41 is then determined and the vicinity of upper seam 24 is S canned to deliver a masked multilevel gray image signal including only the seam part 24 to a defective image detecting circuit thus detecting defective pixel in the subwindow 41 region. In this regard, a region obtained by removing the background 45 from the subwindow 41 is set as an region to be inspected thus realizing high speed processing. |
