Research On H.264Video Coding Standard And Application In Embedded Video Surveillance System

In March2003, ITU-T/ISO released the H.264video compression standard. H.264compression performance is very excellent. It is widespread concerned by researchers of different countries. They called it a new generation of video coding standards. In the same quality level, for the previous generation of video coding standard MPEG4, H.264can save almost half rate. This essay is focused on the combination of H.264and embedded system, fast motion estimation algorithm.This essay discusses the key technology in H.264. Such as intra prediction, inter prediction, transform, quantization and entropy coding. After a series of experiments, this essay summarize a set of x264configuration program, which is suitable for monitoring image, and then x264is transplanted to ARM Linux platform. The code is optimized according to the platform. After analysis of the basic principle of the motion estimation, the algorithms of UMHexagonS is researched in the paper. Using the high temporal correlation of motion vector between frames, this essay proposes some improvement:early termination of zero vector, adaptive directional unsymmetrical-cross search and multi-hexagon search. The25points spiral search is reduced to9points.Combining with the platform of embedded monitoring system, analysis of the transplant of the encoder and the experimental results is showed. Experiments indicate the improved algorithm decrease the computational complexity and preserves similar average PSNR value at the same time.