中文摘要：

提出一种针对颅骨缺损重建模型的孔洞修复算法，根据孔洞特征自动提取缺损边缘。通过双环采样，投影构建代理曲面；通过合并环间区域及引入边缘约束的平滑，得到缺失实体孔洞的上下缝合面。在此基础上，搜索出上下边界环之间的三角网格区域，利用几何约束条件重建缺失实体。算法能最大限度的减少人工交互步骤，符合需要的修补结果。

英文摘要：

A hole repair algorithm for skull defect repair is put forward. From the input of a set of guide points, the upper boundary ring for the hole is searched according to edge features and the position of the objective point. The expanded ring is obtained by the expansion of the upper ring along the gradient direction. And the boundaries of objective regions are recognized, while the region between this two rings is obtained. Based on two samples rings, the lower boundary ring is constructed by the inward expansion of the upper ring, and the region between the upper and lower rings is identified. Then the lower patching surface is constructed by using geometric constraints. The repair entity is constructed by stitching the upper patching surface, lower patching surface, and the region between the upper ring and lower ring. The algorithm can minimize the manual interaction steps and produce a satisfied repair result.