| 摘要 |
PROBLEM TO BE SOLVED: To separate three-dimensional point groups expressing contours of a plurality of features into point groups of each feature unit by analyzing the three-dimensional point groups.SOLUTION: Three-dimensional point group data expressing contours of a plurality of features are prepared. First, the three-dimensional point group data are divided into floors in a height direction. Then, point groups are separated into clusters belonging to the same feature on the basis of inter-point distances in each floor. An attribute indicating an upper surface or a side face of a feature is applied to each cluster. Then, a tree structure is generated by correlating clusters overlapped to each other successively from a cluster of an upper surface to lower floors. A lower cluster to which clusters of the whole feature are correlated is determined as a ground surface and the three-dimensional point groups are separated in each feature unit on the basis of clusters belonging to upper floors of the ground surface. Consequently, even when a feature of a complicated shape having a branch or the like is included, three-dimensional point groups can be suitably separated in each feature unit. |
