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一、引言会议电视的概念不是最近才出现的。早在1930年,在纽约的Bell实验室和AT&T总部展示了一个双向的以模拟信号传输的可视电话系统。由于模拟信号传输的成本较高,因此会议电视的发展缓慢。进入70年代末和80年代初,各国竞相研究经过信息压缩的数字会议电视系统。如日本的TRIDEC、NETEC、HasKell和西欧的COST 112方案。这些方案都是以一次群和二次群传输速率为目标进行研制的。日本在1983年于东京-大阪之
I. INTRODUCTION The concept of conference television has not only appeared recently. Back in 1930, Bell Labs and AT & T headquarters in New York City demonstrated a two-way videophone system that transmits analog signals. Due to the high cost of analog signal transmission, the development of videoconferencing is slow. Entering the late 1970s and early 1980s, various countries were competing to study the compressed digital conferencing television system. Such as Japan’s TRIDEC, NETEC, HasKell and COST 112 in Western Europe. These programs are based on the primary and secondary group transfer rate was developed for the goal. Japan in 1983 in Tokyo - Osaka