Dual Watermarking for Handwritten Document Image Authentication and Copyright Protection for JPEG Compression Attacks

摘要

For authentication and copyright protection of handwritten document images, a dual watermarking algorithm that connects the robust watermarking algorithm based on Krawtchouk moments with a fragile watermarking algorithm based on MD5 hash function is presented. Hence, the robust watermarking algorithm is used to guarantee robustness by modifying frequency coefficients in Krawtchouk moments. Thus, this study proposes a fragile watermarking algorithm, which can perceive in time when the protected image is tampered. Experimental results show that the proposed algorithm can be used for copyright protection for JPEG compression attacks and tampering detection of this images.