The Transplantation And Optimization Of H.264 Intra Prediction Algorithm Based On DM642

H.264 is the newest video compression standard, which is published by ITU-T (Intenational Telecommunication Union) and ISO (International Orgnization for Standardization). Compared with earlier standards, H.264 obtains a better image quality, lower bit rates, and enhances the network adaptation and the capacity of error resilient at the same time. So H.264 has been so widely used in various fields of digital video. However, the excellent coding efficiency of H.264 is at the cost of increasing the coding complexity. So in order to achieve the H.264 codec in realtime environment, it not only needs optimazition in theory, but also requires high performance real-time processing chip. The high performance DSP provides an effective platform for H.264 Codec.First of all, this paper studies the coding process of H.264 and proposes a fast mode decision algorithm based on the spatial correlation aimed at intra prediction. Then this paper transplants one of three major open-source codes X264 of H.264 into DM642, and optimizes the code using variable optimization methods. Finally, this paper designs a real-time H.264 coding system frame based on DSP/BIOS. The whole paper is composed as following:First, this paper proposes a fast mode decision algorithm for intra prediction. This paper aims at the intra prediction, proposes a fast mode decision algorithm based on the spatial correlation between the adjacent blocks and the correlation between different mode directions. The proposed algorithm reduces the time of mode decision and saves the coding time of H.264. The simulation experiment results show that the proposed algorithm can save the coding time by more than 50 percents, with only a little PSNR loss and bitrates increase. Secondly, this paper transplants X264 into DM642 platform. This paper choosesSEED-VPM642 as the hardware platform, chooses DSP inregrated development envitonment CCS as the software platform. This paper transplants X264 into DM642 DSP at frist. Then this paper allocates the memory spaces on SEED-VPM642 poperly and adjusts the code structures, data types, header files and library files according to the CCS integrated environment, which enable X264 code to run accurately in CCS.Thirdly, this paper optimizes X264 which has been transplanted using many methods. Frist, this paper optimizes the whole code using project-level optimization and C language-level optimization according to the characteristic of X264 and the instruction structure of DM642. Then this paper optimizes the key codes such as intra prediction, intager DCT transform, quantization and SAD/SATD/SSD using linear assemble language. Besides, cache, EDMA and DSP/BIOS optimization strategies are adopted. Experimental results show that the optimization improves the coding speed.Finally, this paper designs a frame of real-time H.264 encoding system based on DSP/BIOS, which can achieve video capture, video encoding and video transmission.