| 摘要 |
PURPOSE: To surely and efficiently detect the micro local change of two similar images by performing an orthogonal transformation by a block unit and comparing and qualifying the coefficient estimated value. CONSTITUTION: From each of two images to be comparison objects, a block B2... are segmented by shifting the block B1 consisting of N×N picture elements of the N picture elements which are continous in the longitudinal direction of a screen (wherein, N is a positive integer) and the N picture elements which are continuous in the lateral direction by less than N picture elements in the longituidinal and lateral directions. For each of block pairs at the same location of the two images, the density function of the picture element density to the picture element location as a variable is orthogonally transformed by a preliminarily fixed orthogonal function system. The estimated value of expansion coefficient when the function is expanded and approximated into finite number of terms is calculated. Then, for each of the block pairs, the presence or absence of the change between the block pairs is detected by a stastistical test by using the estimated value. |
