Multi-point conference system and conference terminal device

摘要

A multi-point conference system includes a plurality of conference terminal devices coupled to each other, image information and voice information being transmitted among the plurality of conference terminal devices so that users of the plurality of conference terminal devices are in conference with each other. A coding process unit of a transmission side conference terminal device codes image information by switching an intra-frame coding operation and an interframe coding operation and transmit coded image information when the each of the plurality of terminal devices is specified by a speaker specifying information item. The coding process unit of the transmission side conference terminal device which is specified again by a speaker identifying information item codes image information by an interframe coding operation starting from a head frame. A decoding process unit of a receiving side conference terminal device which receives the coded information from the transmission side conference terminal device decodes the coded information by the decoding operation corresponding to the interframe-coding operation using reference image information last stored in a frame memory portion corresponding to the transmission side conference terminal device.