采用数学形态学方法,在地物群识别的基础上进行地物群概括。地物群的识别采用两个标准,即地物群内部间距的阈值与地物群内部间距和外部间距的比值。同时,还在地物群内识别面积相似、间距相似、排列方向一致的规则结构单元。在此基础上,首先进行规则结构单元的概括,在选取、合并、移位、夸大的过程中保持规则结构单元的间距相似、排列方向一致等特点。然后进行整个地物群的概括,保持地物群的分布范围、形状等宏观特征。

Many kinds of area features tend to distribute in clusters in map sheets.These clusters usually impress map reader with the concentration of map features.When a generalized map is derived froma detailed map,the pattern and characteristics of cluster distribution should be maintained to some extent.This paper discusses the method of identification and generalization of clusters and regular structural units by mathematical morphology.Clusters are identified based on two criteria,i.e.,proximity between features inside clusters and the ratio between distances inside and outside cluster.Further more,neighboring features with similar size,spacing and orientation are identified as regular structural units inside clusters.After cluster identification,regular structural units are generalized in a way to maintain their characteristic pattern on size,spacing and orientation.Other features inside clusters are generalized associated with theircontext,so thatthe general characteristics and distribution of clusters are maintained.