| The TV set has already walked into huge numbers of families and watching TV has become main recreative content of family culture. But we can only listen to the radio and watch TV passively for ages as the unilateral broadcast mode of TV transmission. Users can not select what they like at their free time actively. Recently, with the development of digital technology and Internet, VOD system which changes the passive style of information acquirement appears.VOD called interactive Video-on-Demand system is the integrated technology of computer, network communication and television technology. With the advantages of Internet and Video, it radically overcomes the passive way of watching TV and completely implements the user's initiative of getting information. VOD not only is the integration of dynamic picture, video, audio, text and so on, but also is the system which can supply real and interactive service according to the user's requirement.In this paper, the concept, structure and the classes of VOD system are firstly introduced, and then the application environment about it is described. Secondly, some key technologies, such as streaming media, Socket telecommunication and DirectShow are related with this VOD system. I also present the basic frame and the on-demand process of this system. In addition, a multi-user and multi-thread assignment plan which can alleviate the tense question of server resources is proposed in the last chapter of this paper. This thought is similar to the P2P which is widely used at present. As a result, a VOD system of point to multi-point can be realized easily.From the research of this paper, an available VOD project is proposed and some key technologies are also resolved. The proposed software realization can basically satisfy the requirements of users for VOD. At the same time, it is a theory groundwork for our future research. |
