Just Noticeable Difference Based Fast Coding Unit Partition in 3D-HEVC Intra Coding
Summary form only given. This paper mainly studies currently developing 3D video coding based on HEVC. HEVC-based 3D video coding mainly focuses on 3DTV and auto-stereoscopic video compression system. A variety of new encoding tools, such as inter-view motion prediction and depth modeling modes, have been added in 3D-HEVC. Although 3D-HEVC provides greater bit rate saving, it also brings the enormous encoding complexity increase. The coding time is increased correspondingly. It is necessary to reduce the encoding time. In this paper, a fast CU-sized partition algorithm is proposed for 3D-HEVC intra coding. The key point of this algorithm is to find the relationship between the texture characteristic and the sub-partition in each CU. It needs to determine whether the LCU can be subdivided to smaller CU according to the relationship. In order to reduce the redundancy of the human eye, just noticeable difference (JND) is a high efficiency model in the base of psychology and physiology. Instead of the time-consuming rate distortion optimization for coding mode decision, the variance of JND in each CU can be exploited to partition the coding unit according to human visual system characteristics. In other words, the larger blocks with higher JND variance will be subdivided to smaller blocks with lower JND variance. Consequently, the rules of CU preliminary partition are decided as follows: (a) For a 64×64 CU, if the variance of JND is larger than 0.25, the CU will be sub-divided into four 32×32 sub-blocks. (b) For a 32×32 CU, if the variance of JND is larger than 0.15, the CU will be sub-divided into four 16×16 sub-blocks. (c) For a 16×16 CU, if the variance of JND is larger than 0.10, the CU will be sub-divided into four 8×8 sub-blocks. The proposed algorithm is implemented based on HTM-13.1 reference software. The experiment condition is set up as "All Intra-Main" (AI-Main) configuration [1]. The quantization parameter (QP) values of texture are set to 25, 30, 35 and 40, respectively and the corresponding QPs of depth can be set to 34,39,42,45. The experimental results show that the fast intra mode decision algorithm provides over 29.25% encoding time saving on average with comparable rate distortion performance.