Rate-distortion aware skip control for sample adaptive offset

The newly proposed Sample Adaptive Offset (SAO) in High Efficiency Video Coding (HEVC) standard enhances the quality of reconstructed frames. Experimental results show that the coding gain from SAO is very different according to video characteristics, whereas the computational complexity of SAO in the encoder side is quite large. Thus, skipping SAO scheme is used in HEVC. However, the conventional SAO uses the fixed threshold to decide a SAO skip. In this paper, adaptive SAO skip control is proposed considering characteristic of videos. As a result, the SAO skip rate is significantly increased with a reasonable decrease in compression efficiency.