| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a tone inspection device and a tone inspection method for objectively comparing and evaluating a difference between tones corresponding to granularity or brightness which is similar to the visual sense of a human by using a tone index regardless of a difference in an inspection condition or the like. <P>SOLUTION: A tone inspection device includes: an FFT arithmetic part 55 for obtaining a contrast distribution image showing the contrast of each spatial frequency by performing an FFT arithmetic operation to image data D1 of an image obtained by photographing a sheet-shaped inspection object; an MTF arithmetic part 56 for determining the contrast sensitivity of each spatial frequency under the consideration of the brightness of the photographed image and an observation visual field with respect to the image; and a local tone index arithmetic part 57 for calculating a tone index DX by multiplying and adding the contrast distribution image obtained by the FFT arithmetic part 55 and the contrast sensitivity obtained by the MTF arithmetic part 56 for each spatial frequency. <P>COPYRIGHT: (C)2013,JPO&INPIT |
