The concept of video on demand

VOD is a new type of network media in recent years, which is the product of multidisciplinary and multidisciplinary integration of computer technology, network communication technology, multimedia technology, TV technology and digital compression technology.

Video on demand fundamentally changed the traditional one-way transmission, the user has no right to choose the video program, so that users can not only watch the fixed program, but also free to choose to store in the video on-demand system video signal, at any time on demand to see their own programs. The VOD technology has aroused people's concern as early as the 1970s, but its application scope has the very big limitation at that time. With the rise and development of "information superhighway", the advent of digital compression technology makes video-on-demand system enter a new field, and provides various solutions for industry users to meet the needs of users.

At present, VOD technology has been widely used in the fields of enterprises, military, hotels, libraries, archives, museums, network teaching, automobiles, trains, ships, airplanes, shopping malls, hospitals and communities. In a sense, this is a way for the recipient of information to improve themselves and develop themselves according to their own needs. In today's information society, this approach will increasingly meet the deep needs of consumers of information resources. It can be said that VOD is the mainstream way of information acquisition in the future.

Video-on-demand (Vedeo on Demand), which is played as required video stream. When the user turns on the TV. Can not look at ads, not for a program to rush time, at any time directly on demand want to watch content. It's like playing a new movie that just put it in a VCR or Vcd/dvd machine, but you don't need to buy a videotape or Vcd/dvd machine, and you don't need a VCR or a vcd/dvd machine. An important dream of information technology is to send video streaming to millions of households through multimedia network. Looking at the application of broadband network, VOD is the most close to the people's lives, but the technical difficulty of VOD is also the largest. Take China Telecom to say: The highway has, must have the car to run. VOD application is the most eye-catching car on the broadband multimedia network.

VOD technology can not only be used in the broadband network of telecommunication, but also can be applied in the community LAN and CATV broadband network. Nowadays, in the process of building intelligent community, computer network wiring has become an indispensable link. Community users can use computers, televisions (with set-top boxes) and other means to achieve VOD video-on-demand, enrich people's cultural life. Cable TV through a two-way transformation, so that the vast number of TV users through the cable TV network on demand video programs.