文档介绍：摘要
近年来,国家广电总局大力推动广播影视数字化发展,各地也加快推进数字电视整体转换工作。今年数字电视“整体转换”将全面开花。视频点播是数字电视增值业务中最重要的增值服务之一。
VOD 系统中需要构建一个与用户进行信息交流的平台—用户接入系统[1]。如果对所有发出点播请求的用户都进行“一对一”的分配,那么整个网络的频道资源将被很快消耗完,不利于点播业务的大规模开展。通过汇聚管理对点播请求进行处理,以满足服务用户多,而频道数量又有限的具体情况。通过播出子系统来响应用户点播请求,完成节目的播放和机顶盒对频道的切换。
本文通过分析数字电视点播业务的发展态势及相关的技术背景,结合目前广播电视网络的特点,分析一套用于数字电视城域点播的用户接入系统的设计思想及其实现方式。该系统利用 PSTN 网络作为上行点播信号的传输信道,以 CTI技术为基础,依靠语音卡硬件为用户提供了电话接入方式[2]。通过使用系统,数字电视用户可以拨打电话的方式与点播系统进行交互,从而享受高效、安全、快捷的点播服务。汇聚管理部分主要根据频道资源有限的具体情况,提高了整个系统服务质量。并从呼叫中心接口设计、数据库设计、客户端界面实现等方面进行了介绍。在用户点播成功之后,为了视频服务器响应用户的点播要求、播放用户点播的节目,下发控制指令让机顶盒接收点播的相应内容,设计和实现了播出子系统。
【关键词】数字电视视频点播通用对象请求代理结构计算机电话集成 HFC
ABSTRACT
The development of Digital Broadcast Video has been energetically impulsed by the NBTA (National Broadcast Television Association) recently. At the same time, the whole conversion of DTV (Digital TV) in broadcast region has also been improved. The VOD (Video-On-Demand) is one of the most important accessorial operations in DTV.
In VOD System,Users Access System is a municated with subscribers. It is easily to run out of channel resources if reply every user who sends request, it is bad for the development of the VOD in large scale .To solve problems above mentioned, Converging System is a optimal choose and Broadcasting System can reply requests from users.
The paper propose a Users Access System can be applied in VOD by analyzing trend of VOD and relative technology and associating with Broadcast works. The project adopts work as uploading transmission channel, bases on CTI technology, and provides Phone Access for users making use of speech board. Using the Users Access System,the DTV users can enjoy efficient,safe and quick VOD services by calling phones municate with VOD system. Converging System is not only achieve all functions essfully integrated with Call Center, database design and client interface, but also advance quality of service well. At last, in order to let video server apply the demand and broadcast the programs and let the