An image processing apparatus includes an image output apparatus and an image reading apparatus. The image output apparatus includes an input object information receiving unit that receives first input object information, a first information image generating unit that generates a first information image, a second information image generating unit that generates a second information image, a first combining unit that combines the first information image with a document, a second combining unit that combines the second information image with a document, and a first output unit that outputs the document. The image reading apparatus includes a first reading unit that reads an information image including first input object information, a second reading unit that reads an information image including second input object information, an extracting unit that extracts the first and second input object information, and a determining unit that determines whether these pieces of information correspond to each other.