It is determined whether each block (51) including a plurality of pixels extracted from a basic field (30) has an edge or not, and then which state, stationary or non-stationary, each of the pixels forming together the block (51) determined to have an edge is. There is calculated an absolute value of a difference between a pixel determined to be non-stationary and a pixel (91 or 92) in each pixel position in a reference field (40) or pixels (82 to 85) included in the reference field and adjacent to the non-stationary pixel, and a correlation is found between such pixels in consideration according to the calculated difference absolute-value. A motion vector is determined by the block matching method according to results of the determination, and allocated to each of the pixels. Thus, the motion vector of each block is corrected to an accurate one of each of the pixels.