1. Niu, X.M., Shao, C.Y., Wang, X.T.: A survey of digital vector map watermarking. Int. J. Innov. Comput. Inf. Control 2(6), 1301–1306 (2006)
2. Feng, J.B., Lin, I.C., Tsai, C.S., Chu, Y.P.: Reversible watermarking: current status and key issues. Int. J. Netw. Secur. 2(3), 161–170 (2006)
3. Tian, J.: Reversible watermarking by difference expansion. In: Workshop on Multimedia and Security, Tualatin, pp. 19–22 (2002)
4. Yang, B., Schmucker, M., Funk, W., Bush, C., Sun, S.: Integer DCT-based reversible watermarking for images using companding technique. In: Security, Steganography, and Watermarking of Multimedia Contents VI, San Jose, CA, vol. 5306, pp. 405–415 (2004)
5. Arno, V.L., Michiel, V.V., Fons, B.: Reversible image watermarking. In: Proceedings of the International Conference on Image Processing ICIP, Barcelona, vol. 2, pp. 731–734 (2003)