| 摘要 |
PURPOSE:To separate and identify ranks of defects by extracting a to-be- detected frequency component of a signal by the action of a matrix operator, returning to an original image from a defect position data determined by binarization or the like, and calculating the characteristic amount. CONSTITUTION:A two-dimensional image taken by a CCD camera is stored as an original image in a frame memory. After a to-be-inspected area of the stored image is masked, a Laplacian operator 13 performs a secondary differentiation of the to-be-inspected area, thereby to remove low frequency components and filter and obtain a Laplacian image signal 14 of a high frequency region. A binary image signal 15 obtained by binarizing the signal 14 with a predetermined threshold value is expanded and degenerated to remove isolated points and parts of holes. Thereafter, labelling is carried out through a geometrical treatment, whereby an area where a defect is present is specified from the labelled image area. In this manner, the position where the defect exists is determined and the characteristic amount of the signal is calculated from the original image corresponding to the position. Accordingly, it becomes possible to separate and identify ranks of defects. |
