A robust and encrypted digital image watermarking method against print-scan

The growth of network multimedia systems has expanded the demand for image copyright protection. Digital watermark is one approach which is often used for image copyright protection. However, there are limitations of robustness and confidentiality in the common digital watermarking algorithms to resist print-scan attacks. In this paper, a new method combining zero watermarking, blind watermarking and Arnold scrambling is proposed. The zero-watermarking algorithm in DCT low-frequency region avoids the limitation of watermarking capacity to a certain extent. And it has a certain degree of stability and adaptability as well as a strong anti-interference ability to the geometric attacks. In the intermediate-frequency region, the blind watermarking algorithm is used to embed the scrambling information of the watermark and it is robust. With such multilayer enciphering, the confidentiality of the watermark is improved. The whole method has made great progress in the resistance of the geometric attacks and confidentiality of watermark. It´s proved that the method is an applicable method against print-scan attacks. It has a certain reference value to the study of digital image watermark.