IMAGE PROCESSING APPARATUS WITH DETECTION OF MOTION VECTOR BETWEEN IMAGES, CONTROL METHOD THEREFOR, AND STORAGE MEDIUM STORING CONTROL PROGRAM THEREFOR

摘要

An image processing apparatus that is capable of improving the alignment accuracy by detecting a motion vector accurately even if there is a low contrast region or a repeating pattern region. A division unit divides each of inputted images into blocks of a predetermined size. A first determination unit determines whether contrast in a block is less than a predetermined contrast for each of the blocks. A size changing unit changes the size of the block concerned when the first determination unit determines that the block concerned is low contrast. A motion vector detection unit detects a motion vector by comparing images in each pair of corresponding blocks between the images.