1. An image processing system for generating a processed image depending on an input image, the system comprising: an image processing portion configured to add, to the processed image, an AR marker which is an image for identifying missing information missing from information of the input image when the processed image is generated; an AR content generating portion configured to generate an AR content corresponding to the missing information; an AR content registration portion configured to store, into a storage portion, the AR marker and the AR content in association with each other; a camera for photographing the processed image which is printed or displayed; an AR marker recognizing portion configured to recognize the AR marker contained in a photographed image obtained by photographing the processed image by the camera; and an AR display processing portion configured to display the AR content stored in association with the recognized AR marker in the storage portion in a manner to be superimposed on the processed image photographed by the camera.