Copyright protection of e-government document images using digital watermarking

This paper examines means to achieve e-government documents security through the use of digital watermarking techniques. An effective algorithm is proposed such that a given e-government document is watermarked in the frequency domain by applying a second order Discrete Wavelet Transformation (DWT) followed by transformation of the document through matrix decomposition techniques such the Singular Value Decomposition (SVD). Non-reversible embedding of a well-defined watermark is then carried out on the diagonal elements of the of DWT-SVD decomposed document. Experimental results are presented to showcase the performance of the proposed algorithm with respect to imperceptibility, through the examining the peak signal-to-noise ratio of the original and embedded images, and with respect to robustness, through the measurement of the correlation coefficient between the embedded and the extracted watermark images. Attacks examined here are the Gaussian noise, the Salt & Pepper noise, and the JPEG Compression. Performance results demonstrate the effectiveness of the proposed algorithm.