An Effective Strategy for Early Skip Mode Decision in HEVC

High Efficiency Video Coding (HEVC) can provide up to twice better compression efficiency than its predecessor, H.264/Advanced Video Coding (AVC) but its high encoding complexity is a main obstacle for practical applications. In this paper, an early SKIP mode decision scheme is proposed to reduce the complexity of inter mode decision in HEVC. The proposed method firstly employs the merge_flag information of spatial neighbouring candidates for the SKIP mode. In case the best spatial candidate of the SKIP mode is encoded with merge_flag equal to one, the rate-distortion (RD) cost value of $2\mathrm{N}\times 2\mathrm{N}$ Merge or inter $2\mathrm{N}\times 2\mathrm{N}$ PU mode is further exploited to determine the early SKIP mode for the current CU. Experimental results show that the proposed method can provide on average 39.07% encoder speed-up for an average 0.53% bitrate increase in Random Access (RA) main configuration compared to the HEVC test model (HM) 16.13 reference software.