Low Complexity Trellis-Coded Quantization in Versatile Video Coding

The forthcoming Versatile Video Coding (VVC) standard adopts the trellis-coded quantization, which leverages delicate trellis graph to map quantization candidates within one block into optimal path. Despite high compression efficiency, complex search with soft-decision may hinder applications due complexity and low throughput capacity. To reduce complexity, in this paper, we propose a scheme scientifically sound way theoretical modeling of rate distortion. As such, departure point can be adaptively adjusted, unnecessarily visited branches are accordingly pruned, leading shrink total stages simplification transition branches. Extensive experimental results on VVC test model show that proposed is effective reducing encoding by 11% 5% all intra random access configurations, respectively, at cost only 0.11% 0.05% BD-Rate increase. Meanwhile, average 24% 27% time savings achieved under configurations. Due excellent performance, has adopted implementation scheme.