Image forming apparatus and copy management system

Additional data useful for the management of copies of a document for an image forming apparatus is embedded in a hard copy of the document. The additional data is embedded in an image of a document as discrete dots arranged in a prescribed format. Preferably, the size of each of said discrete dots is such as not to be recognized easily with the naked eye. The image data for embedding the additional data can be obtained by reading a document, or by receiving data sent from a computer. Additional data embedded in a hard copy can be extracted from the image data on the hard copy. Further, the production of a copy according to the image data can be controlled according to the extracted additional data. Additional data is generated for each copy according to the extracted additional data for embedding it in a hard copy to identify each copy.