A Hole Repairing Algorithm For 3D Skull Model

The holes repairing of the 3D model is a challenging issue in the field of computer graphics. Because of the particularity of the skull model, the previous algorithms are not suitable for the skull hole repairing. 3D skull hole repairing is to use 3D computer graphic technology to repair the hole of skull according to the geometry and topology information of the skull model. According to the limitations of the previous algorithms, a novel automatic hole-repairing algorithm for arbitrary holes in mesh surface models of the 3D skull is proposed. The experimental results show that our method is more efficient and has better results compared with previous methods, especially for the complex skull holes. The main contributions are as follows:(1) A novel skull hole repairing algorithm is presented. After reviewing and analyzing the previous hole repairing algorithms, we presented a novel skull hole repairing algorithm according to the limitations of the algorithms existed and the particularity of the skull model. Firstly, the holes are detected by searching boundary points of model automatically. Secondly, the discrete points are interpolated into the hole and then triangulated. Thirdly, the triangular mesh is subdivided. Fourthly, an implicit surface of hole is generated to adjust the position of these interpolated points. Finally, the patch mesh is optimized by laplacian smoothing.(2) An advancing layer-wise solution (ALS) method is proposed. In large holes repairing, the traditional holes repairing approaches use the points of hole to control the shape of the internal area, but it's hard to get the ideal patch mesh when the internal shape is adjusted only by a little control points. In order to solve this problem, an advancing layer-wise solution (ALS) method is proposed to improve the limitations of the traditional methods which make the patch mesh too flat. The ALS method splices the patch mesh and source mesh of model smoothly, and gets the ideal experimental result. (3) A 3D skull hole repairing system (SHRS) is designed and implemented, which could realize the all function of skull hole repairing and is applied to 3D craniofacial reconstruction system. For the small hole, the system triangulates the hole directly, and for the big hole, the discrete points are interpolated and then triangulated. The system can adopt the implicit surface to adjust the interpolated points, and for the large hole, the ALS method is applied to generate the implicit surface.