| 摘要 |
PURPOSE:To enable precise positioning by using appreciation function made by combining two indexes, i.e. correlation coefficient and difference in density of each picture element of two pictures and thereby enabling highly accurate correction of positional deviation between the two pictures. CONSTITUTION:Two pictures, a pair of positionally deviated pictures #1, #2 are divided into plural local areas P11, P12, P21...Q11, Q12, Q21... which are thought to be uniform in positional deviation through a local area dividing section, and correlation coefficient of nearby area is determined for each area. Then, rough position correction that repeats shifting in the plant of the picture to a position that makes the value maximum through a position correction object local area designating section and a rough position correcting section. Then, maximum value of variation of correlation coefficient in nearby area becomes less than previously given threshold value. At this point of time, highly accurate correction is made by repeating shifting in the direction to make the appreciation function made by combining density difference of two picture elements and correlation coefficient, and thereby precise positioning is performed. |
