三维物体的形态图表达方法

A Representation Method Based on aspect Graph for 3D Objects

三维物体的表达方法是计算机视觉中的关键问题之一 ,现有的各种三维物体表达方法虽然在各自的识别中得到应用 ,但都存在各自的局限性 .用形态图表达三维物体是一种以视点为中心的表达方法 ,由于它列举了一个物体所有可能的“定性”形象 ,即它可使用最少的二维投影线图 (特征视图 )来表达一个完整的三维物体 ,因此使三维物体识别转化为 2 D与 2 D的匹配 .该文首先定义了二维线图拓扑结构等价的判别准则 ;然后给出了构造透明物体形态图的方法 ;最后根据拓扑结构等价准则来得到不透明物体的形态图和特征视图 ,并用圆锥与圆柱相交的实例进行了验证 .

The 3D object representation method is a key problem on computer vision. The existent methods of 3D object representation have applied for 3D object recognition. But, they have themselves drawback. The 3D object representation method based on aspect graph is a kind of means on a center of the observant. It completely describes the 3D object by a finite set of 2D views of the object from different viewpoint. According to geometry structure of object, the set of viewpoint on the viewing space is partitioned into regions such that in each region the equivalent structure of the line drawing is consistent. An aspect is defined for the same of qualitative structure of topology of the line drawing. The 3D object representation method based on aspect graph makes 3D object recognition become problem on matching 2D image and 2D aspect. To begin with, The thesis defines a principle of equivalent structure of topology for the line drawing. In addition, it studies the partition theory and structure method of aspect graph for 3D object of transparent under perspective projection. At last, according to the principle of equivalent structure of topology, the aspect graph for 3D object of opaque and aspect are established. At the same time, it is proved for example of 3D object.