Image processing device and an image processing program

Abstract

According to an aspect of the present invention, provided is an image processing device comprising a saturation value acquisition unit configured to acquire a saturation value of a target pixel or a saturation value of a target small area including a target pixel and peripheral pixels around the target pixel, and a correction unit configured to correct the target pixel so that a corrected gradation characteristic obtained by correcting the target pixel matches a gradation characteristic synthesized by mixing a color gradation characteristic and a monochrome gradation characteristic at a predetermined mixing ratio based on the saturation value, wherein assuming that the saturation value is c, and the mixing ratio of the color gradation characteristic is W, a value of W is represented by variable c as a relationship W=f(c) and satisfies a following condition. Condition: There is a saturation value c and a multiplier a which satisfy f(c)>αg(c), and α≥1, wherein a relationship in which the mixing ratio W increases in proportion to the saturation value c is W=g(c) and the saturation value is equal to or greater than a threshold value.