Research And Optimization Of Mode Decision And Motion Estimation Of Inter Prediction In H.264

Interframe prediction coding is used to eliminate the large amount of temporal and spatial redundancy that exists in video sequences and helps in compressing them. Motion eliminate can help to eliminate these redundancy. Different kinds of algorithms use different criteria for comparison of blocks. One of the first algorithms to be used for block based motion compensation is what is called the Full Search or the Exhaustive Search. It can exactly get the very motion vector. Because of its large computational complexity, people tried many other methods. Some algorithms are based on the nature of the image data than the limitations of the human observers. It is believed by these algorithms that very good matches are likely to be found in the vicinity of reasonably good matches.Based on the H.264 video coding standard, this paper proposes a new algorithm for fast block-matching motion estimation. Considering the relativity between the front frame and the back frame, using SKIP pattern and comparing the Rdcost of the block, deside the best mode in advance. This paper proposes a new algorithm for fast motion search-- Diamond-hexagon-square Search. It combines the advantage of both TTS, HS and DS and makes the search result more effective. It also makes the computational complexity more accretive. Its central idea is based on the classic diamond-shaped, and the strengths and weaknesses of other fast search algorithm, combined with the existing video applications, under the premise that the running time and computational complexity fit in with the requirements of real-time premise, proposed a new algorithm having relatively good results in video compression for sequences with various degrees of movement, especially the more violent sports video. With the program simulation in the PC and optimization of the original before the algorithm for comparison, my analysis prove its feasibility.This paper analyzes the main factors which affect the two new algorithm's performance and illustrates the principle by which some important parameters can be evaluated. According to the programming, experiment and analysis of the algorithm, it has good efficiency.