1. An image processing method, comprising: setting a correction target area in a correction target image based on a plurality of input images and correcting the correction target area by using at least one of the plurality of input images as a correction image; and determining a reliability of the correction target area being in a foreground, comprising, a first reliability determination based on a size of the correction target area and a second reliability determination based on a relative value that represents the relative relationship between the respective plurality of input images and a reference image associated with the plurality of input images, wherein correcting the correction target area based on the reliability.