基于深度预测的HEVC编码单元快速划分算法  

FAST PARTITION ALGORITHM FOR HEVC CODING UNIT BASED ON DEPTH PREDICTION

作　　者：赵宏[1] 蒋雨晨[1] 李靖波[1] 

机构地区：[1]兰州理工大学计算机与通信学院,甘肃兰州730050

出　　处：《计算机应用与软件》2017年第5期229-233,共5页Computer Applications and Software

基　　金：国家自然科学基金项目(61262016);甘肃省高校基本科研基金项目(14-0220);甘肃省自然科学基金项目(1208RJZA239)

摘　　要：高效视频编码HEVC(High Efficiency Video Coding)采用计算复杂度较高的率失真优化方法对编码单元CU(Coding Unit)划分进行判决,具有较高的时间复杂度,编码所需时间较长。为降低HEVC编码复杂度,加快编码速度,提出一种基于深度预测的CU快速划分算法。首先依据当前CU与周围相邻CU和参考帧中当前位置CU的深度相关性,预测当前CU的最优深度,然后使用相邻相关分割法或依据当前CU深度和预测深度的关系对当前CU进行递归划分。为减少预测带来的误判,在CU深度级别由2级到3级的划分中,使用率失真或百分比的方式进行二次判定。实验结果表明,该算法与原始的HEVC编码方法相比,在亮度峰值信噪比减小0.07 d B,编码比特率增加0.88%的情况下,整体编码单元划分时间缩短37.7%,具有较高的时间效率。A rate-distortion optimization method with high computational complexity is used for CU( coding unit)mode decision in HEVC( High Efficiency Video Coding),which has high time complexity and needs a long encoding time. In order to decrease the coding complexity of HVEC and accelerate the coding speed,a CU fast partition algorithm based on depth prediction is proposed. First,according to the depth correlation between the current CU and the surrounding CU and the current position CU in the reference frame,the optimal depth of the current CU is predicted.Then,the adjacent splitting method or partition decisions based on the relationship between the current depth and the predict depth of the current CU are used to split recursively the current CU. In order to reduce the misjudgment caused by the prediction,in the CU depth level by the two to three levels of division,we use rate distortion or percentage of the way to determine again. Experimental results show that compared with the original HEVC coding method,the algorithm reduced the coding time by 37. 7% when the peak signal-to-noise ratio is reduced by 0. 07 d B and the coding bit rate is increased by 0. 88%,which has high time efficiency.

关 键 词：高效视频编码(HEVC) 深度预测 快速划分 编码单元(CU) 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]