The Design Of A Video Processor Based On High-Performance YHFT DSP

The advent of digital video systems,such as video conference,video telephone,standard definition television (SDTV) and high definition television (HDTV) has significantly changed the way people communicate with each other and enjoy themselves. Furthermore,digital video technology is considerably advanced by the unification of different digital video standards which apply for different application environment .The development of digital video technology also promotes the advance of digital signal processing technology,providing more opportunities for Digital Signal Processor(DSP) to find its way in video conference,video telephone, SDTV ,HDTV.But it is also a great challenge to develop real-time, high-performance digital video systems with high complexity,due to the bandwidth of memory system,processing capacity and power consumption of DSP.At present,the market of application-specific video processor is mainly shared by foreign companies,with no corresponding product in such area has been launched by domestic company.Therefore,it is highly necessary to design a application-specific video processor with independent intellegence-property based on YHFT DSP which is designed independently by computer school of NUDT in order to meet the domestic requirement for application-specific DSP for video/audio signal processing in the forthcoming age of digital video.At the beginning of this paper,several popular video compression/decompression standards have been introduced,and discussion about current mainstream media processors in the world is also dealed with in detail.In the end of chapter 1,the necessity and feasibility of designing a video processor with independent intellegence-property is analysed and justified based on the previous discussion.In this paper,a software MPEG-2 SDTV video decoder is implemented based on YHFT DSP.We have also discussed algorithms in the different stages of the video decoder and their requirement for processing capacity,memory bandwidth and power consumption of YHFT DSP.A high-performance video processor----YHFT-VDSP is put forward, combining the previous discussion and the different design schemes of current mainstream media processors in the world.The detailed design scheme of YHFT-VDSP is described based on the justification of the rationality and feasibility of YHFT-VDSP. Speedup of YHFT-VDSP relative toYHFT DSP in terms of video signal processing peiformance is also discussed in detail.The application of 2-dimension DCT/IDCT in video compression/decompression is also discussed,followed by the adjustment on a fast 2-dimension IDCT algorithm in order to faciliate the hardware implementation of the algorithm.In the latter of this paper,We discussed a high-speed,parallel hardware implementation of IDCT---- a part of YHFT-VDSP,based on the adjusted algorithm.Finally,The EDMA system of YHFT VDSP is implemented based on the EDMA of YHFT DSP. Interconnection between EDMA and on-chip video port is also designed.At the end of this paper,Functional simulation and verification on The EDMA system of YHFT VDSP is done based on testbench which is designed according to the particularity of video application systems to represent real environment.