| Along with Internet in global scope daily popularization, swift and violent development of mobile communication, the demands of multimedia service of realized by the network transmission is increasing all the time.Many new requests have been set arranged to the encoding and decoding technology of video.How to provide the higher and more steady transmission quality become hot spot in information science and the technical research.This paper realizes the real-time decoder of H.264 based on DSP, referring to the JM8.6 code.Firstly, this paper present the background of video technology, the development of DSPs(Digital signal processors) and the DSPs's applications of video.We also present the characteristics of the Blackfin ADSP-BF533 DSP. At the core to ADSP BF 533 processor produced by ADI Company,paper construct the decoder of the H.264, according to the characteristic of ADSP BF 533, it optimizes the Algorithm of H.264 Baseline Profile Decoder, prepares link description file, does Optimal allocation to Cache using Conversion operations, and finish the decoder on PC platform. On this basis, it standardizes data type, changes grammars, and realizes the transplantation of H.264 decoder from PC platform to DSP platform. Against the request of real-time application, the paper analyzes every components of the decoder.It gives the Optimization Software Series of decoder based on reference model JM8.6. In entropy module, resolute code table, changes the way of search, can noticeably improves the efficiency lookup, and then improves the operating speed. Interpolation scene, minimization reference frame data can conserve the bandwidth of memory chip in luma pixelinterpolation algorithm. The execution can be improved by removing redundant code and void judgment and big priority probability judgment.Finally, the decoder has been tested on the development board ADSP-BF533 EZ-KIT LITE.The test data shows the decoder real-time decoding results of QCIFformat has achieved. |
PDF Full Text Request