Video On Demand Systems In Radio And Television Online

That Digital Television rises rages tempestuously , and our country decides to stop to imitate the transfer of television from 2015. The Video On Demand System is one of value-added service the most important vocational work in the Digital Television . Research major has been in progress to realizing the two-way Video On Demand at the cable television in the unidirectional network by this paper, and can succeed the implementation in Changzhou's CATV network . The cable television net at present majority are for the one-way transmission , and transform two-way HFC's net needing a large number of fund inputs , and Video On Demand is therefore that this text is studied based on one-way CATV's net the important meaning . This VOD system bases on MPEG-2's protocol, and by way of at the Video server and SQL's database respectively has built programme database and EPG's database , and has designed signal input system , signal processing system , system management and the signal output system , and will convey the data flow that fits DVB standard by way of the available network to the user terminal ( box on machine top ) . At the same time , Subscriber Management System provides user's limits of authority information according to user's paying fee information to the Conditional Access system, and empower . The whole course from the former to the user receipt follows DVB-C's standard formerly . This system algorithm is new and original, and the ideal that transition period that to be the cable television platform from imitates the television to the Digital Television moves evenly realized the two-way Video On Demand is selected .