To enable plural cameras and each camera control system of the plural cameras that corresponds to each camera one to one to transmit information signal by a single transmission method, superimposing camera discrimination information on an information signal of a corresponding camera, putting together the information signal upon which camera discrimination information is superimposed, and transmitting it to each camera by way of a single transmission path.

Camera control units(CCU) 11 to 13 superimpose an intercom sound signal and a camera discrimination signal are superimposed with return video signal to corresponding cameras 21 to 23 and output it. A first repeater 31 executes time base compression and superposition of three inputted signals and converts them into superimposed signals S1 and transmits to the second repeater 32 by way of a transmission path 51, such as an optical fiber cable or the like. The cameras 21 to 23 select signals that match with their camera discrimination signals among the superimposition signals S1. Thus, the camera and the CCU can be connected to each other with a single transmission path 51, and signals to be received can be selected.