Rate control for screen content coding in HEVC

Screen content usually has much different motion characteristics compared with conventional videos, which makes exiting rate control schemes unsuitable. This paper analyses the motion characteristics of screen content and proposes an efficient rate control method for screen content coding, by improving the bit allocation and model parameter adaptation strategies. The proposed rate control algorithm is able to both control bitrate accurately and improve the quality of the entire video sequence. The experimental results demonstrate that the proposed algorithm achieves smaller bitrate errors and better coding performance. Compared with the existing rate control scheme in High Efficiency Video Coding (HEVC) reference software, the proposed algorithm improves the coding efficiency by 5.6% on average while obtaining smaller bitrate errors.