Image distortion correction device, storage medium, program, image distortion correction method, an image reading apparatus and an image forming apparatus

摘要

PROBLEM TO BE SOLVED: To correct a scanned image of bound originals even when the back of the originals is perpendicular to the direction of horizontal scanning at the time of scanning. SOLUTION: The outer rectangle containing each character is extracted from a binary image obtained by thresholding an scanned image (step S1). The amount of distortion of the scanned image is estimated by using the change in the shape of the extracted rectangle of the character and the change in the background gray level of the scanned image (steps S2-S9). The scanned image or the binary image is subject to magnification on the basis of the estimated amount of distortion (step S10). Thus, if the back of the bound original is perpendicular to the direction of horizontal scanning at the time of scanning, since the shape of the rectangle of each character changes, the scanned image of the bound originals can be corrected.