Rate Control in Versatile Video Coding with Cosh Rate–Distortion Model

In this paper, we propose a rate control (RC) scheme for versatile video coding (VVC) to enhance coding performance. First, we propose a rate–distortion (R–D) model at the coding tree unit (CTU) level to describe the R–D relationship. Second, we adjust the quantization parameter (QP) and Lagrange multiplier at the coding unit (CU) level according to visual features to improve the rationality of local coding results. Finally, we propose a model parameter updating strategy to guarantee bitrate accuracy. The experimental results demonstrate that our RC method has better R–D performance with similar bitrate accuracy and better visual quality compared to the default RC strategy in VVC reference software VTM 10.2.