1. An image processing system for generating a processed image depending based on an input image, the system comprising: an image processing portion configured to generate a processed image, wherein, in generating the processed image, the image processing portion is configured to add an augmented reality (AR) marker to the input image, the AR marker being associated with missing information that is present in the input image and missing in the processed image and the image processing portion being configured to output the processed image including the AR marker to a tangible recording medium; 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 terminal operably connected to the storage portion of the AR content registration portion, the terminal comprising: a camera configured to photograph the tangible recording medium to generate a photographed image; an AR marker recognizing portion configured to recognize the AR marker contained in the photographed image obtained; 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; wherein the AR content comprises image data on a missing image and position data indicating a positional relationship between the AR marker and the missing image.