Image processing apparatus, image processing program, image processing method, and storage medium

An image processing device includes: a size acquisition section that acquires a first display size of an output target display device that performs 3D display; a storage section that stores respective parallax amounts adjusted by a user during performing 3D display of 3D display image data respectively on display devices of different types, and stores respective second display sizes of the display devices; a parallax amount computation section that computes a parallax amount for the first display size based on a relationship between the parallax amounts and the second display sizes stored in the storage section; and an output section that outputs to the output target display device the computed parallax amount and the 3D display image data.