1. An image forming device comprising: a section that accepts image data including a plurality of pixel data; a detecting section that detects, when an image based on the accepted image data is to be enlarged at a specific zoom level, whether a pattern, distinct from the image, indicating that unauthorized use of the image is inhibited is included at any place in an entire area of the image or not, and detects whether a pattern, distinct from the image, indicating that copying of the image is inhibited is included in an area to be enlarged in the image or not; and an image forming section that forms an output image based on an image, for which the detecting section has detected that the patterns are not included separately in the entire area of the image and the area to be enlarged, and does not perform an output process according to an image, for which the detecting section has detected that the pattern indicating that unauthorized use of the image is inhibited is included in the entire area of the image and the detecting section has detected that the pattern indicating that copying of the image is inhibited is included in the area to be enlarged.