Fast HEVC inter prediction algorithm based on spatio-temporal block information

Abstract

High Efficiency Video Coding (HEVC)is the latest video coding standard established, which introduces a number of new coding tools such as hierarchical structures of coding unit (CU), prediction unit (PU) and transform unit (TU) to improve the compression capacity of encoding. Compared with H.264/AVC, the compression performance increased by nearly 50% at the cost of the algorithm complexity increasing significantly. One of the most time-consuming part is the inter coding process taking over 60% of the encoding time. In this paper, in order to reduce the computational pressure on the encoder side, we design an algorithm based on spatio-temporal characteristics of the encoding pictures. First, we adopt a CU depth pruning strategy based on the texture feature and motion information of the blocks. Then, based on the motion vectors (MVs) of adjacent coded blocks, we introduce a fast reference picture selection strategy. Experimental results show that the proposed algorithm achieves 50% time saving on average with negligible loss of coding efficiency compared with HEVC reference software HM16.9.