1. An authentication image creation device comprising: memory means that, for each of a plurality of pixels making up an original image, stores pixel data indicating a display color of that pixel; update pixel obtaining means that obtains pixel data of at least one pixel that has been selected according to a positional relationship between the at least one pixel and a target pixel in a specific location of the original image; update data specifying means that specifies update data for an image processing device to compare against pixel data of a pixel corresponding to the specific location of a target original image based on the pixel data of the at least one pixel obtained by the update pixel obtaining means, so as to determine whether or not to allow stereoscopic processing for creating a stereoscopic image that includes a plurality of images having parallax from that target original image; and data processing means that alters the pixel data of the target pixel stored on the memory means based on the update data specified by the update data specifying means.