| 摘要 |
PROBLEM TO BE SOLVED: To correct image data so that a main image section is properly reproduced even when a gradation of the major image part in an original image is extremely high or low. SOLUTION: A mean gradation balance curve is obtained from lots of image data, individual reference density to correct a color balance is obtained from preliminary scanning image data, and a mean reference density representing mean gradation balance of lots of images is obtained from the individual reference density and the mean gradation balance curve and whether or not a picture element corresponding to the individual reference density is a picture element corresponding to a major image part in the image (252-266). When the picture element is a picture element not corresponding to the major image part, a weight coefficient corresponding to each reference density is decided to obtain a weighted mean density so as to decide the color balance conversion condition (270-274). When the picture element is a picture element corresponding to the major image part, the color balance conversion condition is decided based on the mean reference density (276). When fine scanning image data are received, the color balance is corrected based on the color balance conversion condition. |
