| 摘要 |
PROBLEM TO BE SOLVED: To achieve high accuracy upon automatic detection of an unevenness area by image processing in an inspection step.SOLUTION: A pre-process unit (21) includes a plurality of filters for calculating a background pixel estimation value of an attention pixel from a pixel value at a position of a plurality of pixels in the vicinity of the attention pixel, and the plurality of filters are configured as a first-order or second-order array. An interval of the plurality of pixels constituting the array and an orientation of the array are different in respective filters, and each of the plurality of filters is used to an unevenness inspection object image to calculate each background pixel estimation value in the attention pixel. Statistical processing is performed to each calculated background pixel estimation value, and thereby a background image is generated by selecting one background pixel estimation value suitable for a background pixel for each attention pixel. |
