An image forming apparatus includes an identification-mark making unit. The identification-mark making unit makes a page identification mark for identifying a page, on a predetermined position of a paper sheet during printing. The identification-mark making unit, based on the page identification mark made in a previous printing, includes a correction/addition mark that indicates an existence of a correction page or an additional page since the previous printing in a part of the page identification mark when a new print output is performed.

An image forming apparatus includes an identification-mark making unit. The identification-mark making unit makes a page identification mark for identifying a page, on a predetermined position of a paper sheet during printing. The identification-mark making unit, based on the page identification mark made in a previous printing, includes a correction/addition mark that indicates an existence of a correction page or an additional page since the previous printing in a part of the page identification mark when a new print output is performed.

Certain embodiments provide a marking apparatus that including a determination section configured to determine the type of a medium on which an image is formed with decolorable image forming material, a recording section configured to record a mark indicating the decolored times of the image on the medium on which the image is formed with the decolorable image forming material, and a change section configured to change a recording method of the mark recorded by the recording section according to the determination result of the medium determined by the determination section.

According to one embodiment, a system for a decoloring information management of a decoloring apparatus includes an decoloring processing unit, a sheet conveying unit, a sheet reading unit, a user ID reading unit, a storing unit configured to store a predetermined information, and a control unit. A sheet on which an image is formed with an decolorable colorant is subject to decoloring processing. The sheet conveying unit conveys the sheet and causes the sheet to pass through the decoloring processing unit. The sheet reading unit is arranged further on an upstream side than the decoloring processing unit. The user ID reading unit reads ID information of a user. The storing unit stores predetermined information. The control unit controls the storage unit to correlate the user ID and the read information by the sheet reading unit.