Patent ID: 7386269

Claim:
An image forming apparatus comprising: an image-processing unit performing a predetermined image processing of an input image data; an output unit printing an image on a copy sheet based on the image data after the image processing; a Z-folding device connected to the output unit and performing a Z folding of the copy sheet; and a control unit controlling the image-processing unit and the Z-folding device so that the image data is rotated in a rotation direction conforming to a Z-folding direction specified by a user, and the Z folding of the copy sheet is controlled with the rotated image data, wherein said rotation direction is one of clockwise by 90 degrees and counterclockwise by 90 degrees, and wherein the control unit is provided so that, when passing of the copy sheet through the output unit is not allowed for a size of the image data rotated in the rotation direction conforming to the specified Z-folding direction, the rotation of the image data is canceled and the image is printed on the copy sheet without performing the Z folding.