A fast SHVC coding scheme based on base layer co-located CU and cross-layer PU mode information

The extended format of HEVC, Scalable HEVC (SHVC), has been developed to serve users with mobile devices under heterogeneous networks. The SHVC can provide different bitrate, resolution, or quality formats of the same video through the one-time encoding process. As the SHVC is developed based on the HEVC, its time complexity is high and has to be reduced for practical applications. In the SHVC, it has to select one best encoding mode, from different CUs, PUs and TUs, to achieve best RD-cost encoding. In this work, we proposed to utilize two fast encoding schemes to speed up the SHVC encoding process: (1) We utilized the encoding depth information of the co-located CU of the base layer (BL) to reduce the candidates in determining the current CU coding depth of the enhancement layer (EL). It can reduce 47.59% of encoding time for the EL video; (2) We utilized the correlation between spatial, temporal and inter-layer PUs to predict the complexity of the current PU, which can reduce the PU mode decision operation steps. It can also be used to determine whether to SKIP or not to eliminate unnecessary processing steps. It can reduce 58.43% of the EL encoding time. Experiments showed that the encoding time can be reduced 70.52% when both schemes are utilized.