A digital camera which is an image processing apparatus is controlled so that a first image and a second image are acquired for the same subject in different timings. A plurality of correction tables for use in shading correction are prepared in advance in a shading ROM of the digital camera. When a first image and a second image are acquired, multiplication of one correction table is performed on both images by a shading correction circuit. As a result of this, a shading correction is effected on both images. The first image and the second image that have been subjected to the shading correction are taken into respective image memories, and after being subjected to a positioning process by a general controller, they are synthesized to generate a synthesized image.