利用DFT幅度和相位构建矢量空间数据水印模型

A Construction of Digital Watermarking Model for the Vector Geospatial Data Based on Magnitude and Phase of DFT

针对矢量空间数据的特征,提出了利用离散傅里叶变换(DFT)幅度和相位构建矢量空间数字水印模型的方法.首先将矢量空间数据进行DFT,将水印信息嵌入DFT系数的幅度和相位中;然后做逆变换,得到嵌入水印的矢量空间数据,对其进行攻击后提取水印.实验结果证明,该模型能保证数据的精度,对数据平移、一定比率的随机删点、旋转、格式转换、缩放等具有稳健性.

For the characteristics of the vector geospatial data, the construction of the digital watermarking model for the vector geospatial data is proposed based on the magnitude and phase of discrete Fourier transform （DFT）. The vector geospatial data is transformed into the DFT domain. The watermark is embedded in the magnitude and phase of the DFT coefficient range, then the watermarked coefficients is performed an inverse DFT （IDFT） and get the embedded vector geospatial data. Experiment shows that the model can assure the data accuracy. It will be robust for the translation, deleting a certain ration vertices at random, rotation, format transformation and scale etc.