1. An image processing device which subjects image data read from an original document to image processing according to a page-background color of the original document, comprising: a page-background color removal section which removes the page-background color from the image data; a page-background color determination section which sorts the image data into either one of a plurality of groups according to the page-background color of the original document; a plurality of color correction tables being provided so as to respectively correspond to respective page-background colors of the groups, each of the color correction tables having (a) image data before subjected to color correction and (b) image data after subjected to color correction, which are associated with each other; and a color correction processing section which subjects the image data to color correction by using a color correction table, among the color correction tables, corresponding to the group into which the image data is sorted by the page-background color determination section.