CAJ | 학술논문

UMHexagonS算法是H.264/AVC所采纳的整像素的快速运动估计算法之一,该算法在保持良好的率失真性能的前提下,相比全搜索算法（FS）可节约70%的运算量。根据UMHexagonS算法的特点,可从三个方面对该算法进行优化：加入零运动块判决;改进的5＊5螺旋搜索;优化的多层次六边形搜索。仿真实验结果表明,在保证PSNR和码率几乎不变的情况下,优化算法可有效降低运动估计时间,从而提高H.264/AVC编码器的实时性。
UMHexagonS산법시H.264/AVC소채납적정상소적쾌속운동고계산법지일,해산법재보지량호적솔실진성능적전제하,상비전수색산법（FS）가절약70%적운산량。근거UMHexagonS산법적특점,가종삼개방면대해산법진행우화：가입령운동괴판결;개진적5＊5라선수색;우화적다층차륙변형수색。방진실험결과표명,재보증PSNR화마솔궤호불변적정황하,우화산법가유효강저운동고계시간,종이제고H.264/AVC편마기적실시성。
UMHexagonS is one of the fast motion estimation algorithms adopted by H.264.It saves nearly 70% computational work compared with the Full Search Algorithm,and still keeps a good rate-distortion quality.The characteristic of UMHexagonS is analyzed,and then three improvements are proposed,including zero-motion block pre-determination after starting point prediction;improvement on 5*5 spiral search;optimized multi-grid hexagon search.Experiment results showed that the algorithm could save motion estimation time effectively and improve the real-time performance of the encoder with little change in PSNR and bite-rate.