Based On Ts Stream Of Digital Television Signals To Switch

Digital television (DTV) developed from analogous television. It is the product of electronic, communicational and computer technology. With the economic development and people's increasing demands for television programs in recent years, it is developing fast and bringing us challenges.The paper discusses the method of DTV signal switching, which usually turns DTV signal into analogous signal and then switches it at Vertical Blanking Interval (VBI). DTV signal can be switched directly, which is related to the integrity of packets, the definition of packets in multiplex streams and measures among different frames. The paper proposes the method of switching directly which wasn't available.First of all, the paper studies switching method according to the standard of video compression and provides the experimental results. Secondly, it introduces the hardware and software design. Finally, it gives the author's advices on improvement and future of the system. The paper includes the following aspects:1. It summarizes the development and tendency of DTV all over the world and introduces the function of signal switching and the necessity of DTV signal switching.2. It summarizes the development of MPEG. And it introduces picture compression standard of digital television: MPEG-2, which includes the system structure, data structure of TS packet, the process of the programs de-multiplex and system clock and sync. It also introduces the video part of the standard related to the switching algorithm. Finally, it introduces ASI, which is related to the transport of TS.3. An algorithm is available in this part by researching MPEG-2. The key issearching a switching point in the transport stream and making sure of switching process smoothly. The part also provides the experimental results.4. It introduces hardware design system and parts of chips used in the system. Then it explains some circuit diagrams including the circuits of power, reset and DSP.5. In this part the flow diagram of all the programs, PAT searching, PMT searching and switching are displayed and discussed. Error detection code CRC-32 is discussed in the part. Some of the hardware programs is also discussed including the access of the data, the initialization of EMIF and the interruption of C6713 DSP.6. Finally, the author gives some points of view about the improvement and future of the system.In a word, the method can make DTV signal switch directly and rightly. And there are some possible problems to solve.