Adaptive Dual Tree Structure For Screen Content Coding

The quad-tree plus binary-tree (QTBT) partition structures was adopted into the versatile video coding (VVC) standard. In the QTBT partition structure, a dual tree structure can be applied on intra slices where the partitioning structures for luminance and chrominance components are separate. The dual tree structure is efficient for camera captured videos. However, it may be not the case for screen content videos. Therefore, adaptive dual tree structure is proposed in this paper wherein the coding structure of each coding tree unit is switched between separate and joint coding structure to adapt the textures adaptively. The proposed scheme is implemented into the reference software of the VVC standard-VTM. Simulation results report that up to 4.5% BD bitrate saving can achieve on the typical screen content videos when compared to VTM5.