An ICA-based watermarking scheme resistant to copy attack

As an attacking approach to digital watermark, copy attack has reduced the utility of watermark and posed a threat to copyright protection. In this paper, the image dependent signature is applied to mitigate this attack, which is embedded into the host image synchronously with the watermark. In the detection both signature and watermark can be extracted effectively through independent component analysis (ICA), a classical blind source separation (BSS) technique. By comparing this extracted signature with the one recalculated from the marked image, which describe the host image and the marked image respectively, the legality of the marked image can be identified. Thus the purpose of resisting copy attack can be realized. Simulation results demonstrate the robustness and validity of this proposed scheme.