Research On Motion Estimation Technology Based On H.264 Standard

VCEG(Video Coding Experts Group) and MPEG(Moving Picture Experts Group) published H.264, which is a new standard for video compression coding. Movement estimate is the key technology of video compression, which dominates the performance of compression and the time for calculating. So it is mainly studied to search a brief fast efficient algorithm of movement estimate for video coding. In H.264 there are three new technologies of picture transaction applied in movement estimate. They are multi-reference frame, multiple mode and split-pixel precision. New technologies become a new field for studying. Based on these studies, each procedure in motion estimation was fully researched and algorithms was improved.Firstly, the technology of multi-mode prediction coding for intra-frame and inter-frame was studied. Frequency-domain character of residual data and correlation among prediction modes of neighboring blocks were employed to improve the algorithms in mode selection technology for intra-frame prediction coding. Then, a new mode selection algorithm for inter-frame prediction coding was proposed to eliminate some redundant coding modes that contribute very little coding gain based on analysis of macroblock detail-level and texture directions in video sequences.Secondly, the study on block-based motion estimation was made. A fast block mode adaptive search algorithm(BMAS) was proposed, which made good use of the motion characters of video sequences in mode judging. Searching strategy can be dynamically changed according to different motion modes. The number of searching points was decreased and coding speed was improved dramatically in the proposed algorithm, which makes it more suitable for real-time applications. Finally, experiment was made to estimate the performance of proposed algorithms. Tests and analyzing showed that the proposed algorithms have better performance than existing ones. The anticipated research target were realized.