Patent ID: 8330986

Claim:
An image forming apparatus, comprising: a printing unit configured to execute a single-sided print job in which one side of a sheet is printed and a double-sided print job in which both sides of the sheet are printed; a storage unit for storing print target data as backing sheet image data in a case where a single-sided print job is executed by the printing unit with respect to the print target data; an image reading unit for reading images on both sides of a document that is subjected to image processing; a backing sheet judgment unit for judging whether there is an image that matches a backing sheet image among the images on both sides of the document by comparing the document image data read by the image reading unit with the backing sheet image data stored in the storage unit; an exclusion processing unit for performing processing to exclude from the image processing targets an image which is judged by the backing sheet judgment unit to match the backing sheet image among the images on both sides of the document read by the image reading unit; wherein the printing unit comprises: a first paper supply unit for supplying a backing sheet, and a second paper supply unit for supplying a sheet blank on both sides, wherein when the single-sided print job is executed using the sheet that is supplied from the first paper supply unit, the storage unit does not store the print target data as the backing sheet image data, and when the single-sided print job is executed using the sheet that is supplied from the second paper supply unit, the storage unit stores the print target data as the backing sheet image data.