Method for correcting image information

TLDR: In this article, a test original obtained by drawing parallel lines with equal intervals on a transparent sheet is read out by a transmission type scanner and stored in a RAM of a computer and the positional information of parallel lines of the test image is obtained from the stored information.

Abstract: PURPOSE:To completely remove distortion and to obtain an accurate original image by detecting the characteristic information of an image receiving means and correcting the image of the original based upon the detected result CONSTITUTION:A test original obtained by drawing parallel lines with equal intervals on a transparent sheet is read out by a transmission type scanner and stored in a RAM of a computer and the positional information of parallel lines of the test image is obtained from the stored information After selecting the positional information most close to the center of the image out of the stored information, a deviation value is determined, the positional information of an original parallel lines is estimated by applying least square method and a correction value is calculated from these detecting position information and the estimated position information Then, an errors between two points close to both the ends of the test original is calculated, the deviation value is changed, a deviation value minimizing a difference between respective correction values and a difference between errors is calculated and the estimated position information is obtained by applying the least square method again to use the most optimum correction value as the correcting characteristic information of the scanner Thus, correct positional information can be obtained