Patent ID: 8255900

Claim:
A virtual computer server apparatus which transmits image information generated by operating an application program to a terminal via a network comprising: an image information memory to store the image information upon dividing into pages, the page being a memory of a predetermined size; an update unit configured to update the image information stored in the image information memory in accordance with operation of the application program; an update page detection unit configured to detect an update page from the pages storing image information transmitted to the terminal and displayed by the terminal as a display area, the update page being an page which includes the image information updated by update unit; an update image detection unit configured to detect the image information updated by the update unit from image information in the update page before updated and image information in the update page after updated; a transmission image generating unit configured to generate transmission image information from the image information updated detected by the update image detection unit; a transmission unit configured to transmit the transmission image information to the terminal; and a backup memory to store the image information of the page before updated, wherein the update image detection unit (a) detects the image information updated by the update unit, the image information being a difference between the image information of the update page before updated and the image information of the update page after updated, when the image information of the update page before updated is stored in the backup memory, and (b) detects the image information of the update page after updated by update unit, when the image information of the update page before updated is not stored in the backup memory.