To display a digital image stream distributed via a network on a large screen comprising a plurality of displays, to automatically set the network when connecting the plurality of displays to the network, and to automatically grasp the position relationship between the displays.

A system composing the screen by connecting the displays having a network interface has a means for extracting the position relationship among the displays from the connection relationship among the displays, and maintaining the position relationship among the displays and the network address mapping information of the displays. In this case, the system has a variable length coding means for reconfiguring the digital image stream transmitted via the network as data to a desired display, and coding the reconfigured data; and a means for configuring the coded data as network packets, and transmitting/receiving the data via the network interface.