Geometry Parametrization Stabilization For Dynamic Mesh Coding

The Video-based Dynamic Mesh Coding (V-DMC), currently under development by the MPEG-3DGH group, employs a simplification and approximation framework for geometry coding. First, the input mesh is simplified into a base mesh with fewer faces, edges, and vertices. The base mesh is then subdivided and deformed to approximate the original mesh, with the offsets between the subdivided mesh and the deformed mesh referred to as displacements. Optimizing both the base mesh and the deformed mesh is crucial to achieving high coding quality. This process is termed geometry parametrization in V-DMC. In this paper, we propose a stabilization method for geometry parametrization in V-DMC to ensure robust results. Experimental results on the MPEG VDMC test sequences show that our method not only enhances the numerical stability of the geometry parametrization process but also improves quantitative coding performance and visual quality. Specifically, our method achieves BD-rate improvements over the anchor of -0.2%, -0.2%, -0.2%, -0.2%, and -0.2% for D1, D2, Luma, Cb, and Cr PSNR metrics, respectively. The proposed method has been adopted and integrated into the MPEG V-DMC reference software.