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图文电视(Teletext)是一种将图形和文字以数字信号形式叠加在电视信号场逆程空闲行中传送的新型电视广播方式,用户可以使用图文电视专用接收设备或普通电视机附加图文电视解码器,解出接收到的数据并显示在屏幕上。这是一种利用现有的电视广播网进行数据广播的多工技术,可以廉价、快捷地实现点对面单向传输大量数据信息。国外自七十年代初开发研究图文电视,八十年代开始在四十多个国家和地区得到实际应用并取得巨大的经济效益。
Teletext is a new type of television broadcasting method in which graphics and texts are superimposed on digital television signals in reverse free-space of television signal fields. Users can use Teletext-specific receiving equipment or ordinary televisions to attach pictures TV decoder, solve the received data and display on the screen. This is a multiplex technology for data broadcasting using the existing television broadcasting network, enabling large-scale data information to be transmitted unidirectionally across the board inexpensively and quickly. Since the early 1970s, foreign countries have been studying the development of teletext. Since the 1980s, they have been applied in more than 40 countries and regions and have achieved enormous economic benefits.