顾及曲线走向及局部面积特征的矢量数据压缩算法

The Algorithm of Vector Data Compression Take into Consideration of the Curve Trend and Local Aera Feature

目前,矢量数据压缩算法存在曲线压缩精度与压缩效率不能共存的问题,基于此,本文以带有径向约束的Douglas-Peucker算法为基础,提出一种顾及曲线走向和局部面积特征的矢量数据压缩算法。该算法首先通过带有径向约束的Douglas-Peucker算法提取曲线的特征点;然后,提取各个局部曲线段形态特征点以判断局部曲线段走向特征;最后,根据曲线段走向对预先提取的各个特征点的位置进行局部微调,完成矢量数据的压缩。该算法创新在于通过局部微调特征点位置的方式使压缩后曲线较好地反映了原曲线的局部走向,并且减小了曲线局部面积偏差。实验表明所提算法在保证压缩效率的同时能够有效降低局部位移偏差和面积偏差,使压缩后曲线较好的反映原曲线形态特征。

Now,most of vector data compression algorithm have the problem that when improving the compression precision they will sacrifice the compression efficiency.In order to solve the problem,the algorithm of vector data compression based on structural and local aera features was proposed in this paper.Firstly,extract the characteristics of the curve bymeans of Douglas-Peucker algorithm with radial constraints;Secondly,extract the feature points of each local curve to get the trend of the curve;Finally,minor adjustments for each feature point done with the help of feature points extracted in advance.The innovation of the algorithm is that through the way of local removement of the feature points the curve will reflect the original curve trend and reduce the area deviation.Experimental results showed that the algorithm can reduce the displacement deviation and size deviation when ensuring the compression efficiency and better retain the original curve shape characteristic.