Abstract: In the compression of vector data, the commonly used methods may make the position of some key points relative to the closed region changed. In the application of petroleum exploration vector, these key points are usually the position of wells. So this factor would result in the wrong geological interpretation. This paper presents a method to keep the key points to improve the compression algorithm for finding out the change of the relative position of the key points, and then determine the compression zone where causes the variation, with certain rules to add or eliminate these anomalies. This method solves the practical problems in the application.

Key words: vector data, Douglas-Puck compression algorithm, key point constraint

摘要： 矢量图数据压缩中，常用的方法可能会使一些关键点相对于闭合区域的位置在压缩后发生变化。石油勘探矢量图应用中，这些关键点通常是井位位置，从而造成错误的地质解释。提出了利用关键点保持的方法来改进的压缩算法，查找出相对位置有变化的关键点，判断造成其变化的压缩区域，按照一定的规则添加或排除这些异常点，解决了应用中的实际问题。

关键词: 矢量数据, 道格拉斯-普克压缩算法, 关键点约束