Inter-Frame Reference Dependency Motivated Initial Quantization Parameter Selection for Screen Content Video Rate Control Using VVC

Rate control (RC) plays a crucial role in video services, with the aim of improving video quality while meeting the channel bandwidth constraint. Initial quantization parameter selection (IQS) is one of the key techniques in RC, which significantly affects the performance of RC. The IQS recommended by the state-of-the-art VVC standard ignores the important influence of inter-frame reference dependency (IRD), resulting in low coding efficiency. To address this issue, an IRD motivated IQS method for screen content videos (SCVs) using VVC, referred to as IRD-IQS-SCV, is proposed in this paper. First, the theoretical analysis and experimental verification are conducted to prove that the IRD is a key factor influencing the IQS. Then, a novel bit allocation model considering the IRD is created. Furthermore, the bit allocation model is effectively solved through the interior point method and the designed SCV classification method, upon which the IRD-IQS-SCV is formulated. Compared with the IQS method recommended by VVC, the average BD-rate corresponding to the IRD-IQS-SCV is -7.13% for all test sequences, with BE savings of 2.59%, quality fluctuation degree reduction of 3.58%, and computational complexity savings of 4.78%.