| 摘要 |
PROBLEM TO BE SOLVED: To provide an image reading apparatus in which a streak of gradation is prevented from being generated by sensitivity variance. ! SOLUTION: A CPU 3 calculates streak data Pd by subtracting full pixel average data Ps of gray zone image data from average data Pv in a sub scanning direction of the gray zone image data (S26). In the case where it is determined that background color data are not white (S35: NO), the CPU 3 executes streak correction processing for correcting vertical streaks of a manuscript M by using the streak data Pd (S36). Therefore, images of not only a white manuscript and a black manuscript but also of a halftone manuscript can be read without influence of sensitivity variance, and a streak of gradation can be prevented from being generated by sensitivity variance. ! COPYRIGHT: (C)2015,JPO&INPIT |
