A watermarking method with a new SS technique

dAmong numerous techniques of information concealment, Spread spectrum watermarking (SSW) has proved to yield improved results when robustness against attack is at a premium. SSW hides information which is called watermark by spreading its spectrum and then adding them to a host image as a watermarked image. Spreading spectrum is done by a pseudo-noise (PN) sequence. But in standard SSW approaches, receiver must use a separate channel to achieve PN sequence used at the transmitter for detecting hidden information. The unique PN sequence must have a low cross correlation and thereby can be duplicated easily by hostile attackers. In this paper a novel approach based on the unconventional Random Encoding Spread Spectrum is proposed for recovering the spreading sequence of watermark signal without any information from the transmitter. It is contributed a higher secure feature by using of the time-varying random encoded spread spectrum.