Exploiting inter-layer correlations in scalable HEVC for the support of screen content videos

In this paper, we propose a scalable video coding (SVC) scheme for efficient coding of screen content videos while still providing the backward compatibility of HEVC (High Efficiency Video Coding). By this means, the base layer is encoded as an HEVC-compatible bitstream while the enhancement layer is encoded with the proposed screen content coding (SCC) techniques for the support of screen content videos. For the enhancement layer, Base Colors plus Escape Colors (BCEC) approach is used in which a textual block is represented by base colors, escape colors and an index map. To further enhance the coding efficiency of enhancement layer, inter-layer intra prediction for BCEC is introduced by using index map differential coding and index map reuse techniques. Experimental results show that the proposed algorithm can achieve 8.0% bitrate reduction in average and up to 18.9% bitrate reduction for screen content video as compared with the conventional scalable HEVC.