Screen Content Coding (SCC) is the extension of High Efficiency Video Coding (HEVC). Main target of SCC is saving BD-rate for screen videos generated by computers. However encoding time is increased because of new intra modes named Intra Block Copy (IntraBC) and Palette mode to save BD-rate. This paper proposes Sharp Edge Based Classification (SE BC) and Directional Edge Based Classification (DEBC). SEBC classifies Largest Coding Units (LCUs) based on sharp edge features and DEBC classifies LCUs based on directional edge features. Then needless mode and depth are skipped. Experimental results show 10.9% time saving with 2.10% BD-rate increase in average for screen videos at the SCC reference software (SCM3.0 ).