Patent ID: 7559031

Claim:
A video display apparatus comprising: a receiving unit configured to receive a composite video image generated from a plurality of video sources; a display unit configured to display the received composite video image; an area manager configured to store area information pieces; a position specification unit configured to specify a position on the composite video image displayed by the display unit; an area selection unit configured to select an area information piece from the area information pieces stored in the area manager; an area display unit configured to provide information indicating the area represented by the area information piece selected by the area selection unit to the display unit so as to superpose the information on the displayed composite video image; an area change unit configured to change the information; an area information update unit configured to update the area information piece selected by the area selection unit stored in the area manager according to the information obtained after the change; and a control signal transmission unit configured to generate an update control signal containing the area information piece after update, and transmit the update control signal to a generation source of the composite video image.