| In recent years, the television system has gone through the analog black-white television to the analog colored television and to the digital television. At present, the television system has been changed from analog television to digital television. The huge digital television market has brought the enormous potential opportunity for the development of the digital television equipment. In this paper, a new idea about realizing a completely programmable digital television source decoder based on generic DSP is presented. According to the capability of the current generic DSP, the hardware system of digital television souce decoder based on the generic DSP, TMS320C6415, is described and realized. In the system, the hardware implementation of the transport stream input, video displaying and audio playing has been resolved. In addition, high-speed data exchange between on-chip and off-chip memory space is implemented successfully with hardware means. This system can also acts as image-capturing and image-matching systems. The key algorithms of the digital television source decoder, including transport stream demultiplex, audio decoding and video decoding, have been researched and developed. In order to meet with the performance requirement of source decoder, many methods have been adapted to optimize these algorithms. Many new functions have added to the real-time operating system μC /OS. A multi-task real-time schedule strategy based on the operating system has beed provided to schedule multi-tasks, such as transport stream input, demultiplex, video decoding, audio decoding, video display, audio output, etc. The experimentations haved showed that the scheme offered in this paper can implement the functions of digital SDTV source decoder. For the limitation of processor's capacity, HDTV source decoder has not been realized. But with the development of DSP, the completely programmable solution of HDTV source decoder with single chip of generic DSP will be feasible.
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