【摘要】 本文介绍了一个自行研制的电视会议系统。该系统由三个终端和一个多点控制器构成。它已在沈阳、长春和哈尔滨三点之间通过数字微波信道实现了会议电视通信，信道速率为2Mb／s。实践表明，该系统有良好的图象质量和声音质量。本文介绍了系统构成、系统的主要性能、工作原理及设计原则。对H．261图象压缩编码与G．722声音压缩编码部分作了较详细的介绍。更多还原

【Abstract】 A video conferencing system designed byElectric Power Administration of Northeast China and ShanghaiJiaotong University is presented. This system consists ofthree terminals and a MCU. Using this system the videoconferencing communication among Shenyang. Changchunand Harbin through an existing microwave channel isrealized. The bit rate of the system is 2. 048Mb/s. Theexperience shows that the video and audio quality of the system aregood. This paper describes the architecture, thespecifications, the operational principle and the consideration indesign of this system. The video codec of H. 261 and audiocodec of G. 722 are described in detail.更多还原