Boundary-Preserved Geometry Video for Dynamic Mesh Coding

In this paper, we present a Boundary-Preserved Geometry Video (BPGV) framework for dynamic mesh coding (DMC) with time-varying geometry, connectivity and attributes. The geometry video is generated by interpolating the 3D XYZ coordinates in the sampled 2D UV charts, and can be coded by any video codec to remove the spatial and temporal redundancies. However, the reconstruction from the geometry video itself may suffer from serious distortions because of the missing boundary information of the UV charts. Therefore it is proposed to code the boundary information of the UV charts in a separate sub-bitstream by efficient prediction and residual coding. The connectivity information can be inferred from the decoded geometry images and the boundary information via triangulation with linear complexity on the decoder side. Better coding performance can be achieved by leveraging the trade-offs between bitrate and quality from the proposed coding tools, including the adaptive chart sampling and the raw-chart coding mode. The proposed BPGV framework was submitted as a response to the MPEG’s CfP on DMC and the results demonstrated its superior performance compared to a state-of-the-art mesh codec.