Efficient coding mode and partition decision for screen content intra coding

In order to tackle the exclusive characteristic in the screen content video, new coding tools such as intra block copy mode and palette mode are adopted in the screen content coding (SCC) based on high efficiency video coding (HEVC) standard. It results in high coding complexity for SCC and is hard to satisfy real time applications. An efficient intra coding algorithm for screen content video is proposed in this paper. Early skipping or early termination of coding unit (CU) partition and mode prediction is applied to speed up intra coding by exploiting the correlated information among luminance, gradient and neighboring CUs. Furthermore, the correlated information of hit rate and coding bit is revealed and properly used for fast CU depth decision. Experimental results demonstrate that the proposed algorithm obtains significant time saving with ignorable compression loss in comparison with several recent algorithms.