US Patent 7990586 Image forming apparatus for producing booklet

There is described an image forming apparatus, which makes it possible to realize a high productivity in the booklet outputting operation. The apparatus comprises: an image data acquiring section to acquire consecutive image data, which include main content image data and at least a part of cover sheet image data succeeding the main-content sheet image data; an image forming section to conduct an image forming operation based on the main content image data and the cover sheet image data, acquired by the image data acquiring section; an image data presence-or-absence detecting section to detect a presence or absence of (i+1)th image data acquired by the image data acquiring section, wherein “i” represents a page number of image data sets necessary for forming cover sheet images on a cover sheet; and a control section to control the image forming section so as to commence the image forming operation.