Design And Implementation Of High-definition Digital ETV Program Production System

With HDTV and television transmission environment development, if you copy the professional television methods, improve educational television technology that requires expensive hardware investment. The purpose of this study is how to improve the quality, reduce the cost, in the form of innovation, adapt to changes of environment of transmission.This HD digital education television program production system is based on Hunan Cable Group "TV tutor" project as the basis, mainly to do the following research:(1) Designed and implement a simple structure, low-cost system, improving the educational television program production methods.(2) System is PC as a platform, with specialized software to play the advantages of software processing. The main application of the HDMI technology, VJ Director of audio and video switching system,"PC Desktop" recording technology, HD signal processing and low bit rate compression, Vegas nonlinear editing techniques. Functions are standalone hardware professional equipment to complete.(3) Simultaneous subtitles for Vegas editing software is not perfect problem to write extensions using the method of transformation scripts, batch editing of the system to achieve simultaneous subtitle function, eliminating the need of a special caption machine equipment investment, improve work efficiency.The main innovations:(1) The system enables the program to interact between teachers and courseware, the screen real vivid, blackboard and courseware display clear and natural.(2) HDMI interface replaces the SDI interface, and at a lower cost. Solve the brightness and color sampling ratio of4:2:2high-definition digital baseband signal transmission problems. So that the screen has more details, color is more level, the better the high clarity.(3) As the scene of the educational television programs is simple, backgrounds-based, voice spectrum and dynamic range are not large. From the perspective of computer graphics and coding technical analysis, there is a lot of redundant space program. Conducive to compress the amount of data and the use made of pure software systems. So the signal processing and video compression unified planning. Multistage HD signal processing scheme, remove the clutter, enhance the details, to reduce the spatial redundancy, then through low bit rate compression. The HD digital educational television programs in1920×1080/50P format, rate of only1Mbps. Is1/4times as much as the general hardware system, save the network traffic overhead, more conducive to modern television broadcasting environment.