Zhang L.,Lanzhou Jiaotong University |
Zhang L.,Gansu Provincial Engineering Laboratory for National Geographic State Monitoring |
Yan H.,Lanzhou Jiaotong University |
Yan H.,Gansu Provincial Engineering Laboratory for National Geographic State Monitoring |
And 2 more authors.
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2015
In DFT watermarking algorithms, the watermarksare often embedded directly in the transformation coefficients, causing large errors in watermarked data. To overcome such disadvantage of these algorithms, a blind watermarking algorithm for copyright protection of vector geospatial data based on error reduction is proposed. This algorithm amplifies the DFT transform coefficients and embeds the watermarks in the amplitude coefficients and phase coefficients by DFT transform, and the watermark is embedded several times. In addition, the voting principle is utilized to detect the watermark. No original data is needed in the watermark extraction procedure. The experiments have shown that spatial accuracy of the watermarked data is acceptable and the algorithm is robust to a variety of geometric transformation attacks.