| Cartographic generalization is the important part of cartography. With the increasing popularity of computer network and GIS, different network users have different detail requirements for the map. It requires the system has the ability to respond quickly to users'needs, which demands technology support of automated cartographic generalization.This paper is based on the theory of cartographic generalization, including the analysis of cartographic generalization and influencing factors of generalization.Then methods and process in cartographic Generalization are discussed. The content of automated generalization is described in detail, and knowledge rules of automated cartographic generalization are established. Based on the knowledge rules, it analyses the main theories and algorithms of research, which includes mathematical morphology and shape analysis. Through the research on theory and difficulty of algorithm, some algorithms are designed and tested by simulation for automated cartographic generalization. For example, it puts forward " traction algorithm" for patch mergers; compression algorithms are put forward for point and line generalization; In the patch simplification, it puts forward " the convex hull algorithm"; In addition, for the patch boundary inconsistencies, it puts forward central axis of the segmentation algorithm. All of the algorithms are by a number of examples of image to carry out by simulation test. And it has in-depth discussion in robust,universality and cartographic generalization accuracy. At the same time, it points out the problems and research directions in future. |
