Authentication algorithm of secure digital halftone watermark based on SM4 algorithm

Abstract

With the development of information technology, the problem of piracy is getting worse. In order to increase the security of watermark information, this paper has proposed a security watermark authentication algorithm based on SM4 encryption algorithms, which is embedded in the frame of the vehicle image when the watermark information is encrypted. SM4 is the block cipher standard adopted in WAPI of wlan standard in China, and then adopted by commercial cipher standard in China. It is characterized by adding nonlinear changes in the calculation process, which greatly improves the security of the algorithm. Because the watermark information is embedded in the feature points of the structure, which is relatively stable and not easy to change, so the robustness of the watermark is enhanced to a certain extent. Through the test, the algorithm can encrypt and authenticate the watermark information.