[en] The Toshiba Corporation developed a real-time dynamic image transmission matched with quality of transmission circuit by using MPEG-4 which was recent international standard system for the dynamic image coding system. Concretely, this system made possible on real-time dynamic image transmission even at transmission on wireless circuit such as portable telephone, PHS, wireless LAN, and so on, at viewpoint of the mobile communication. And, by using the wireless circuit, it could be built without any limit of transmission cable, to realize its layout-free establishment. In addition, this system uses only image for communication without using voice, and some devices were carried out to upgrade image and frame speed as possible. Here were described on outlines of transmission system and principle of detection MPEG-4, and function and application of monitoring system using this system. (G.K.)