The study of watermarking algorithm for vector geospatial data based on the phase of DFT

Based on the theory of discrete Fourier transform (DFT) and the characteristic of vector geospatial data for digital watermarking, this paper studied the watermarking algorithm for vector geospatial data based on DFT phase. Considering 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 experiments show that the proposed algorithm is robust to the attack of vertex deletion, data format transformation, translation, rotation and so on.