A low delay rate control method for screen content coding

Tong Tang, Ling Li

Abstract: Unlike conventional camera captured video (CCV), the screen content video (SCV) is generated by computer, like text, animation, or graphics. The SCV contents are discontinuous, as one abrupt frame is often followed by many static frames. These distinct characteristics bring challenges to the implementation of rate control in screen content coding (SCC). This paper proposes a low delay rate control method for SCC in HEVC (High Efficiency Video Coding). Firstly, a bit allocation scheme considering buffer status and picture complexity is proposed. Then, an R − MAD (Rate-Mean Absolute Difference)model is built to estimate frame QP (quantization parameter) according to allocated bits. Finally, a dynamical adjusting scheme is designed to fix the error of the estimated frame QP. Experimental results show that the proposed method could effectively avoid buffer overflow and improve the coding efficiency over the recommended rate control scheme in HEVC.