3维图像中边界曲面的分类追踪及抽取

Detection and extraction of boundary surface patches within 3D images

3维图像分析中,边界曲面的检测与重构是一个非常重要的问题。已有的连续隐边界曲面的抽取及逼近计算技术存在着把某些零交叉曲面片错误地识别为边界曲面片的缺陷。为此,提出一个新的边界曲面的追踪及抽取的方法。该方法首先将包含边界曲面的全部立方体分为两类:包含一个连通零交叉曲面片的立方体叫第1类边缘立方体,包含两个及其以上不连通零交叉曲面片的立方体叫第2类边缘立方体;然后根据边界曲面的连续性连通性,便可追踪出两类边缘立方体;对于追踪出的第1类边缘立方体直接提取边界曲面片,对于追踪出的第2类边缘立方体的边界曲面片通过其相邻的第1类边缘立方体来提取。实验结果表明本文方法是可行有效的,而且可以有效地克服已有技术的缺陷。

In 3D image analysis, detection and reconstruction of boundary surfaces is a very important problem. Some methods have been developed for extracting or approximately computing continuous implicit boundary surfaces from 3D images. However, they have the drawback of incorrectly classifying some zero-crossing surface patches as boundary surface pat- ches. In this paper, we present a new method to detect and trace boundary surfaces from 3D images. First, all cubes con- taining boundary surface patches are divided into two categories： cubes containing one connected boundary surface patch, called and first class of edge cubes, and cubes containing two or more disconnected boundary surface patches, called the second class of edge cubes. Then, according to the continuity and the connectivity of the boundary surface, we can track all the edge cubes from both classes. Finally, the boundary surface patches contained in the first class of edge cubes can be extracted directly, and the boundary surface patches contained in the second class of edge cubes are extracted based on the adjacent first class of edge cubes. Experimental results show that the proposed technique is feasible and effective, and can effectively overcome the shortcomings of existing methods.