| 摘要 |
PROBLEM TO BE SOLVED: To ensure the detection of an abnormal part according to changes in image data. SOLUTION: This differentiation means 30 is provided with a notice pixel selection means 31 and an image data stored in an image data memory section 18a is read by a subtraction means 33 sequentially as notice pixel value GN. The differentiation means 30 is provided with a reference pixel selection means 32 and an image data specified by a reference variable X is read by the subtraction means 33 as reference pixel value GN-X. Then, the notice pixel value GN and the reference pixel value GN-X are subtracted by the subtraction means 33 and the results are stored into a differentiation data memory section 18b. Therefore, in the differentiation processing, as the reference pixel can be selected optionally, the reference pixel is selected to maximize the differentiation value ΔGN according to changes in the image data for a pin hole P thereby effectively intensifying the image for the pin hole P. |
