IMPLEMENTATION OF A SECURED WATERMARKING MECHANISM BASED ON CRYPTOGRAPHY AND BIT PAIR MATCHING

Abstract

Watermarking is one of the most vital digital information hiding technique, which can be used with
cryptography mechanism for providing more security to digital data. In image watermarking
mechanism mostly LSB substitution is used on the cover image for hiding the secret watermark. In
this paper, a novel technique based on the matching of bit pairs and symmetric key cryptography is
proposed. Pixel bits of original image and encrypted watermark image are arranged in pairs. The
pixel bits are represented in pairs following the proposed algorithm, then the encrypted watermark
pixel bit pairs are compared with all bit pairs of original image and accordingly the replacement of
bit pairs takes place with the respective matched pair assigned number binary equivalent. If no
match is found then go for replacing the 0th pair with watermark bits and replace the two LSB with
the value of pair number 0. The proposed mechanism shows good quality of watermarked image
along with good PSNR values with a good payload. By com- paring the results with some existing
algorithms, the proposed scheme shows the valuable results