曲边多边形中轴提取的新方法

针对现有多边形中轴提取方法在处理复杂图形和特殊图形上有较大困难的不足以及中轴连通性和位置准确性难以保证等问题，提出了一种曲边多边形中轴提取的新方法。首先在简单多边形的基础上进行拓展，提出曲边多边形的概念，并相应地定义了曲边多边形的中轴，然后在栅格距离变换的基础上引申出最近边缘点集距离均值变换，最后结合曲边多边形中轴点的特征和距离变换的原理制定出高效中轴点判定规则，利用种子点生长判别法提取曲边多边形的中轴，并给出具体实现步骤和流程。通过多组不同类型多边形及道路网与河网的实例验证，新方法不仅能适用于各类多边形，且能较好地抑制图形边界噪声的干扰，提取出具有良好的光滑性、准确性和连通性的多边形中轴，弥补了传统方法的不足。

A New Method for Extracting Curved-polygon Medial Axis

It is difficult for existed polygon medial axis(MA) extracting methods to address complex polygon and to make sure of the accuracy and connectivity of MA.A new curved-polygon MA extracting method is introduced.Firstly,concepts of curved-polygon together with its MA are given.Secondly,the mean distance transformation(MDT) of the nearest border point set(NBPS) is put forward.Thirdly,a new MA point judgment regulations is constructed,and the method of greed points-growth and detection are used to extract MA.Fourthly,various complex polygons were used to inspect this new method.It was found that the impacts of border noisy points are eliminated effectively and both the accuracy and connectivity of MA are satisfactory which overcome the shortcomings of traditional methods.