1. An image processing device comprising: a process output image generation means generating one sheet of a process output image by performing a process using plural sheets of captured images sequentially output from a pickup device in consideration of one of the plural sheets of captured images as a reference image; and a correction means correcting image distortion occurring in the captured images by an optical pickup system including a pickup lens, with respect to the captured images produced in the process output image generation means, when the plural sheets of the captured images are obtained.