利用DFT相位的矢量地理空间数据水印方法

Watermarking Algorithm for Vector Geo-spatial Data Based on DFT Phase

基于矢量地理空间数据自身的特点,运用离散傅立叶变换(DFT)技术研究了基于DFT相位的矢量地理空间数据数字水印算法。由于DFT相位的较小变化也会导致原始数据的较大改变,因此引入自相关检测来辅助判定数字水印的存在。实验表明,DFT相位水印算法在抗矢量地理空间数据处理中常见的删点、数据格式转换、平移、旋转等攻击方面具有较好的效果,并且针对浮点型数据的效果要明显优于整数型数据的结果。

Based on the theory of discrete Fourier transform（DFT） and the characteristic of vector geo-spatial data for digital watermarking,a watermarking algorithm for vector geo-spatial data is studied by DFT phase.Because the little change of DFT phase can cause the big change of original data,the autocorrelation detection is used to assist for extracting digital watermarking.The experimental results show that the proposed algorithm is robust to the attack of vertex deletion,data format transformation,translation,rotation and so on.