To precisely perform alignment of a plurality of image data when generating image data having a large dynamic range.

A region extraction part 106 divides a screen of a plurality of image data into blocks. If an exclusion element inadequate for alignment is included in neither a block as a motion vector detection target nor a block as a reference image with respect to the block as a motion vector detection target, the region extraction part 106 assumes both blocks as common blocks. A level correction part 107 calculates each average value a1, a2 of pixel values in the common blocks so as to adjust each luminance level of the common blocks to be equal to each other by using their average values a1, a2. A displacement detection part 108 detects displacement among a plurality of image data by using the common blocks respectively having the equal luminance level. A position correction part 109 corrects each position of the plurality of image data corresponding to the displacement amount. An image synthesis part 110 synthesizes the plurality of image data whose each position is corrected.