An image forming apparatus, comprising: - a printing control unit including: - a first page information queue; - a buffer memory; - an image processing section; and - a page control section; and - an engine controller including: - a video memory corresponding to a plurality of pages; - a second page information queue; - a counter; and - a video memory control section, wherein the engine controller is configured to increment the counter every time all pages of the job are printed, wherein the image processing section is configured to: i) expand print data into a bitmap as page-to-page-basis image data; ii) store the page-to-page-basis image data in the buffer memory; and iii) write page information to the first page information queue; wherein the page control section is configured to generate a print request including the page information to the video memory control section in an order of records in the first page information queue; wherein the video memory control section is configured to: i) load the page-to-page-basis image data corresponding to the page information in the buffer memory onto the video memory in response to the print request; ii) return completion of the loading to the page control section with the page information; and iii) write the page information to the second page information queue; wherein the page control section is further configured to: i) delete the image data corresponding to the page information in the buffer memory in response to the completion of the loading; and ii) delete the page information from the first page information queue, characterized in that the video memory control section is further configured to: i) convert the image data into a video signal; ii) delete the image data from the video memory based on a value of the counter, said value of the counter being a copy number; iii) delete the page information corresponding to the image data from the second page information queue based on the value of the counter, said value of the counter being a copy number; iv) update the value of the counter without loading the image data onto the video memory, if the print request is a single-sided printing and the image data corresponding to the page information included in the print request exists on the video memory, wherein the updating of the value of the counter includes process for incrementing the copy number by one; and v) load the image data corresponding to the page information in the print request onto the video memory, if the print request is a double-sided printing, or if the print request is the single-sided printing and the image data corresponding to the page information included in the print request does not exist on the video memory. - a printing control unit including: - a first page information queue; - a buffer memory; - an image processing section; and - a page control section; and - a first page information queue; - a buffer memory; - an image processing section; and - a page control section; and - an engine controller including: - a video memory corresponding to a plurality of pages; - a second page information queue; - a counter; and - a video memory control section, - a video memory corresponding to a plurality of pages; - a second page information queue; - a counter; and - a video memory control section, i) expand print data into a bitmap as page-to-page-basis image data; ii) store the page-to-page-basis image data in the buffer memory; and iii) write page information to the first page information queue; i) load the page-to-page-basis image data corresponding to the page information in the buffer memory onto the video memory in response to the print request; ii) return completion of the loading to the page control section with the page information; and iii) write the page information to the second page information queue; i) delete the image data corresponding to the page information in the buffer memory in response to the completion of the loading; and ii) delete the page information from the first page information queue, i) convert the image data into a video signal; ii) delete the image data from the video memory based on a value of the counter, said value of the counter being a copy number; iii) delete the page information corresponding to the image data from the second page information queue based on the value of the counter, said value of the counter being a copy number; iv) update the value of the counter without loading the image data onto the video memory, if the print request is a single-sided printing and the image data corresponding to the page information included in the print request exists on the video memory, wherein the updating of the value of the counter includes process for incrementing the copy number by one; and v) load the image data corresponding to the page information in the print request onto the video memory, if the print request is a double-sided printing, or if the print request is the single-sided printing and the image data corresponding to the page information included in the print request does not exist on the video memory.