Combined watermarking for image authentication and protection

A novel combined watermarking scheme for image authentication and protection is proposed in this paper. By utilizing the publicly available wavelet-based just noticeable distortion (JND) values, the hidden watermark is designed to carry the host image´s information such that blind watermark detection becomes possible. The watermarks are embedded using the previously proposed cocktail watermarking technique and are extracted by a quantization process. According to the polarities and the differences of the hidden and the extracted watermarks, the fragility and robustness of a watermark can be measured, respectively, such that both content authentication and copyright protection are achieved simultaneously