| 摘要 |
PROBLEM TO BE SOLVED: To improve the observed image reading performance of a processed image by setting an absolute value of a function depending on a difference signal based on the difference signal between an original image signal and an unsharpened mask signal. SOLUTION: When an original image signal Sorg obtained by a reader or the like is given to a low pass filter 11, the filter 11 sets a prescribed fog mask to the original image signal Sorg and a fog mask signal Sus is outputted to a 1st arithmetic element 13. The arithmetic element 13 calculates a difference signal between the original image signal Sorg and the fog mask signal Sus and provides an output of the result to a conversion table 12. The conversion table 12 converts the received difference signal into an emphasis signal f(Sorg-Sus) and provides an output of it to a 2nd arithmetic means 14. The 2nd arithmetic element 14 adds the original image signal and the emphasis signal to provide an output of a processed image signal Sproc. As a result, the processed image signal is obtained, in which the sharpness of a desired image part is emphasized. |
