针对HEVC编码单元的二分深度划分算法

为了降低高效率视频编码（HEVC）的编码单元（CU）进行四叉树递归遍历的时间，提出一种改进的编码单元快速划分算法.首先，利用帧间时间域的相关性，提取前一帧相同位置CU的最优划分结构，以预测当前CU的划分深度；然后通过改进编码CU结构划分遍历的算法，减少CTU （Coding Tree Unit）四叉树结构的遍历，即从二分深度开始遍历，在每一步遍历之前，判断是否提前终止遍历.实验表明，与HM15.0中的基准划分算法相比，本文算法能够在保证编码性能的同时，降低了55.4%的编码时间，提高了HEVC的编码效率.

Half Depths Decision Algorithm for HEVC Coding Units

Aiming at the high computational complexity of recursive quad-tree partition of Coding Unit (CU) in High Efficiency Video Coding (HEVC), an improved fast CU partition algorithm of HEVC was proposed. Firstly, based on the temporal-spatial correlation among neighboring CUs, the best partition structure from the co-located position of the previous frames is extracted to predict the depth of partition CU. Secondly, a fast CU partitioning structure decision algorithms are improved to reduce traversal of Coding Tree Unit (CTU) quad-tree structure. It means that the traverse operation begins from the half depths of CU partitions structure, and whether to early termination of traversal is judged before each step traversal. We compare to baseline works in HM 15.0, showing the proposed algorithm can reduce the encoding time by 55.4% while improving the coding performance and improve the coding efficiency of HEVC compared with the quad-tree recursive traversal algorithm.