A robust digital watermarking scheme for media files

In this paper, we present a robust mechanism for digital watermarking in media files. We have combined cryptographic and steganographic operations so that a violator cannot easily change the copyright information hidden inside the files. We propose to use a keyed stream cipher architecture controlled by a key which is the product serial number to transform the hashed information before hiding. And finally, we use the RSA algorithm controlled by the private key of the origin to encrypt the cipher stream along with the product serial number. The encrypted hash function of the copyright information is hidden inside the media file multiple times so that it is difficult for the violator to remove or alter the copyright information from the file, thus making the scheme more robust and secure. Experiments have been carried out by hiding information in various LSB´s of the media samples, the results of which are reported.