The Design And Implementation Of Subtitles Broadcast Television System

In addition to the video and audio, television program also includes subtitles.In the process of creating TV show, creating and playing subtitles for video signal generator and a processor is called subtitles machine, the caption machine is generally used to superimposed text caption in the video signal, further explains the program content, rich TV picture. Such as television logo upper left corner of the screen, notice, advertisement, time, dialogues, songs words, end credits, it is a modern television indispensable equipment for television.Now the subtitles machine, named television caption broadcasting system, although can complete the basic functions, it have been unable to meet the needs of the rapid development of television program production.It has exposed a lot of defects.Such as subtitles separate broadcast, and then superimposed broadcasted caption signal onto the the video signal passage through the caption machine; need a separate subtitle machine and the caption machine is very heavy, and very expensive; during a video aired,superimposed captions cannot freely be edited and changeed; Subtitles system can not play subtitles timed, can not meet the requirements of the broadcasting industry automation.In view of the current caption machine faults, research departments consider to develop a subtitle and video superimposed through subtitles superimposed card broadcast television subtitling system, lab brother tried to develop a television subtitle playing system with a special subtitles superimposed card on Blackmagic, but the caption broadcast effect is not ideal.on the basis of the issue of the existing television caption broadcasting system analysis, design a new adaptation of the realistic demand of caption broadcasting and television subtitles superimposed broadcast system, along with the hardware board card upgrades ceaselessly, new system selected Matrox SD100board developed by Canadian Matrox company as subtitles superimposed card, the card can achieve subtitles and video superimposed and broadcast; software selected Delphi7and Microsoft Visual2005as development platform, combined with the hard disk broadcasting system developmented by Department teacther, the research of TV caption broadcasting system can effectively solve the existing problems, to achieve a good subtitle and video superimposition of broadcast, greatly improved the television program post production work efficiency.First of all, this paper briefly introduced the subtitles and subtitles system, and subtitles system development situation and research status at home and abroad, and described current research of the Laboratory of TV subtitles system, based on the current research status, put forward to develop a new set of TV subtitles broadcast system, the system selected the Matrox SD100board as overlay card for subtitles. Then carried out a detailed introduction to the system requirements analysis and system design, owing to requirements analysis and system design, made clear the main topic to complete two modules:subtitle editing software and the underlying subtitle processing module. Then introduced a new advanced modern software engineering (GRAPPLE) thought to subtitle editing software design, use the idea of object-oriented technology, and use advanced modeling language (UML) modeling in the design stage, design the subtitle editing software detailed. Next, choosed the Matrox SD100board, according to the Matrox DSX.sdk Matrox offers development kits, designed and realized the underlying subtitles processing module, the module can be a good convergence of the upper subtitle editing software and Matrox SD100card. The next descripted each module of the subtitle editing software detailed, and descripted the convergence of a subtitle editing software and underlying subtitle processing module and the system hard disk broadcast the workstations detailed, given the realization of the system. And finally, the problems encountered in testing the TV subtitles broadcast system is the subtitle blinking problem, given the detailed analysis of the problem, and given the Gaussian blur technology solutions. The practical application shows that the method is feasible.