Research and Improvement of the UMHexagonS Algorithm Based on H.264
Zhongkui Lei · Science Technology and Engineering · 2011
Motion estimation is the most time-consuming stage in video compression coding.The video coding standard H.264 has adopted the hybrid Unsymmetrical-cross Multi-hexagon-grid Search(UMHexagonS) algorithm as its fast motion estimation algorithm.The UMHexagonS algorithm is introduced in details and is improved in three aspects.Firstly,an adaptive threshold for early termination is added.Secondly,the 5×5 spiral search is replaced with a new search mode to reduce the number of the search points.Thirdly,the Multi-hexagon-grid Search is changed to Multi-tenpoints-grid Search.The algorithm is implemented and verified in JM10.2.Results show that the improved algorithm can save about 7%—14% motion estimation time than the original one while keeping the similar picture quality.