In this paper, we present a novel technique based on a mixed Error Correcting Code(ECC)-the convolutional code and the repetition code to enhance the robustness of the embedded watermark. Before embedding, the binary watermark is scanned to one-dimension sequence and later inputted into the (3, 1, 2) convolutional encoder and (3, 1) repetition encoder frame by frame, which will improve the error correcting capability of decoder. The output code sequence is scanned to some matrixes as the new watermark messages. The watermarking is selected in low frequency band of the Discrete Wavelet Transform (DWT) and therefore it can resist the destruction of image processing. Experimental results are presented to demonstrate that the robustness of a watermark with mixed ECC is much higher than the traditional one just with repetition coding while suffering JPEG lossy compression, salt and pepper noise and center cutting processing.
J. Tian, “Wavelet-Based Reversible Watermarking for Authentication,” Proceedings of SPIE Security and Watermarking of Multimedia Contents III, San Jose, 21 January 2002, pp. 679-690. doi:10.1117/12.465329
D. M. Thodi and J. J. Rodriquez, “Prediction-Error-Based Reversible Watermarking,” Proceedings of the International Conference on Image Processing of the IEEE ICIP, 24-27 October 2004, pp. 1549-1552.
Y. J. Hu, S. Kwong and J. W. Huang, “An Algorithm for Removable Visible Watermarking,” IEEE Transactions on Circuits Systems for Video Technology, Vol. 16, No. 1, 2006, pp. 129-133. doi:10.1109/TCSVT.2005.858742
M. U. Celik, G. Sharma and A. M. Tekalp, “Lossless Watermarking for Image Authentication: A New Framework and an Implementation,” IEEE Transactions on Image Processing, Vol. 15, No. 4, 2006, pp. 1042-1049.
A. van Leest, M. van der Veen and F. Bruekers, “Reversible Image Watermarking,” Proceedings of the International Conference on Image Processing, Barcelona, 1417 September 2003, pp. 731-734.
J. Yang, M. H. Lee and X. H. Chen, et a1., “Mixing Chaotic Watermarks for Embedding in Wavelet Transform domain,” Proceedings of IEEE International Symposium on Circuits and Systems, New York, 26-29 May 2002, pp. 668-671. doi:10.1109/ISCAS.2002.1011441