Research And Analysis Of Inter-frame Encoding In H.264 Based On DM642

H.264/AVC is the newest video coding standard proposed by the ITU-T Video Coding Experts Group and ISO/IEC Moving Picture Experts Group. Due to the advanced compression performance and the"network-friendly"nature, H.264/AVC is widely uesed in digital telecast, real time video communication, video stream media service, compress &storage, et al. Inter-frame encoding technology is the key technology of video coding standard, it accounts for about 50 to 80 percent of the whole encoding computation. Therefore, for improving the encoding rate effectively, it is significant to study and optimize the inter-frame encoding.In this paper, while analysing the inter-frame encoding technology in H.264/AVC, a fast inter-mode decision algorithm is proposed because of the complication of the inter-frame encoding. First, the mode of SKIP based on picture texture is estimated. Then, image detail is achived according to the high frequency, and used to decide the block-mode. Experimental results show that the one-frame scramble time of fast inter-mode decision is reduced by 57.48% with negligible loss of peak signal-to-noise ratio.The other emphasis in this paper is to optimize the inter-frame encoding in the following aspects of adjusting the encoding flow, C-Program, linear assembly and memory accloation based on DM642. Encoding algorithm is more suitable for the DSP environment by adjusting the encoding folw. Optimization using C-Program is to eliminate the memory relativity and enhance the software-pipeline. And using linear assembly to rewrite the key-code achieved a better performance. The next key problem to realize the real time encoder based on DM642 DSP is to optimize the allocation of the code and data according to the architecture of two-level Cache and EDMA. Experimental results show that encoding frame rate is increased by 5 times on average for picture CIF (352×288) on the premise of keeping the image quality.