High Efficiency Rate Control for Versatile Video Coding Based on Composite Cauchy Distribution

In this work, we propose a novel rate control algorithm for Versatile Video Coding (VVC) standard based on its distinct rate-distortion characteristics. By modelling the transform coefficients with composite Cauchy distribution, higher accuracy compared traditional distributions has been achieved. Based coefficient modelling, theoretically derived R-Q and D-Q models which have shown to deliver in characterizing RD characteristics sequences different content are incorporated into process. Furthermore, establish an adaptive bit allocation scheme, dependency between levels of frames is modelled by factor describe relationship reference to-be-coded frames. Given relationships, as well factor, scheme developed optimal bits allocation. We implement proposed VVC Test Model (VTM) 3.0. Experiments show that due proper allocation, low delay configuration can achieve 1.03% BD-Rate saving default 2.96% fixed-QP scheme. Moreover, 1.29% also observed under random access configuration.