Affine transformation coefficient calculation method and image processing apparatus in image processing

摘要

PPROBLEM TO BE SOLVED: To provide an affine transformation coefficient calculating method for correcting geometrical distortion of a target image, and an image processor for the same. PSOLUTION: The affine transformation coefficient calculating method has a procedure of extracting the circumscribed rectangle of each character of a character string by binarizing the image of the photographed character string, a procedure of calculating some of coefficients of an affine transformation matrix from the center point distance between circumscribed rectangles of a reference pattern corresponding to the character string and geometrical position relation of the circumscribed rectangles of the binarized character string, a procedure of finding the 1st moment matrix of one character image of the character string, a procedure of finding the 2nd moment matrix of a reference image corresponding to the character whose 1st moment matrix is found, and a procedure of finding the remaining coefficients of the affine transformation matrix from some coefficient of the affine transformation matrix and the 1st and the 2nd moment matrixes. PCOPYRIGHT: (C)2004,JPO