1. An image processing device comprising: a first acquiring unit configured to acquire a plurality of parallax images having parallax between one another; a second acquiring unit configured to acquire identification information of a parallax image to be observed from a predetermined observing point position in each of a plurality of regions into which a display area on which three-dimensional image is configured to be displayed is divided, each of the regions including at least one element image, and the element image including each pixel in the plurality of parallax images; a corrector configured to correct pixels at positions corresponding to the regions in the parallax images into pixels of parallax images identified by the identification information; and a first generator configured to generate the three-dimensional image from the parallax images resulting from the correction by the corrector.