基于交叉点的道路曲线化简算法研究

摘要

现有的曲线化简算法不能很好地化简具有交叉路口的道路曲线,针对这一问题提出一种基于交叉点的道路曲线化简算法.算法分为预化简和修正化简两个阶段:首先识别并得到曲线上的分段点,利用相邻的分段点作为道格拉斯-普克算法的首尾点对曲线进行化简,得到预化简的结果;然后对于交叉点引入偏差阈值ε,通过判断道路曲线交叉点与化简后交叉点的距离与偏差精度ε的大小关系来确定该交叉点的化简与保留,如果保留或者化简后的道路曲线没有交叉点那么将原交叉点作为分段点对此段曲线进行重新化简.理论分析与实验结果表明,文中算法能够有针对性地保留或化简道路交叉点以及保持曲线化简后的形态特征.%The existing algorithms on curve simplification can't simplify the road curve with intersections.To solve this problem,this paper proposes a road curve simplification algorithm based on intersections.The first stage is called pretreatment stage,which identifies the segmentation points of a curve,and treats the adjacent segmentation points as beginning and end points of Douglas Peucker algorithm to get the simplified pretreatment results.The second stage is called correction simplification stage,which determines the simplification or deviation of intersections,by introducing a deviation threshold ε,and comparing it with the distance between before-simplification and after.If the intersections are retained or there are no intersections after simplification,redo the simplification by using the previous intersections as segmentation points.Theoretical analysis and experimental results show that the proposed algorithm can retain or simplify the adjacent points purposefully,meanwhile keeping the morphological characters of curves after simplification.