Combined temporal and inter-layer prediction for scalable video coding using HEVC

In the context of scalable video coding, we present in this paper a general prediction mechanism to combine temporal and inter-layer reference signals for compressing the enhancement-layer (EL). By utilizing the proposed combinations, the EL temporal prediction residue can be further predicted from a referenced base-layer (BL) temporal residue; or, the inter-layer prediction residue between EL and BL can itself be temporal predicted, leading to improved coding efficiency. Furthermore, we investigate the complexity associated with the proposed generalized combined prediction method, and present techniques to significantly reduce its worst-case complexity while still achieving substantial coding gains. Simulation results on HEVC Scalable Extension reported average of 1.6%, 2.7%, 4.2% EL+BL BD-rate gains for random access, low-delay B and low-delay P configurations respectively, with only about 2% decoding runtime increase. The worst-case complexity of the proposed combined prediction, in terms of computation and memory bandwidth, is only about 120% and 75% of the worst-case complexity of HEVC temporal prediction.