结合艺术网点的半色调信息组合防伪

针对印品图像均为半色调这一特点,研究结合艺术网点的半色调信息组合防伪方法,实现印刷品多重防伪。设计微观艺术网点H形及圆形网点阈值矩阵;将隐藏信息混沌置乱加密并对加密后的信息预处理生成加网调控信号;载体图像半色调处理过程中,通过调控信号分区域分形状就行阈值矩阵加网,得到既含有微观艺术网点又有防伪信息的半色调图像;防伪信息的提取采用模板匹配法,利用圆形网点模板获取置乱的隐藏信息,反置乱后得到原始隐藏信息。加网图像放大处理后,规定区域的H形艺术网点清晰可见,印品一重防伪认证有效。半色调图像与载体图像相差较小,防伪信息隐蔽性强;且提取的隐藏信息FSIM值均超过0. 9,提取效果优越,达到二次防伪目的。该防伪方法具备双重防伪效果,防伪信息潜藏性与提取性优越,为包装防伪的应用研究提供了新的技术方案。

Research on combined anti-counterfeiting of halftone information based on artistic dot

For the print image is halftone,we research the combined anti-counterfeiting of halftone information based on artistic dot to realize multiple security of prints. First,The threshold matrix of H-shape and circle dots was designed.Then, hidden information was scrambled and generated control signals to screening by encrypted information.In the halftone processing of carrier image,disparate regions of image was screened by control signals using the different dot shapes of threshold matrix,and halftone image containing both micro-art dots and anti-counterfeiting information was obtained.Template matching method was used to extract the anti-counterfeiting information. Experiment utilized the circular dot template to obtain the scrambled hiding information, and then getted the original hiding information after reverse scrambling.In the specific area of screening images, the H-type artistic dots were clearly, so the printed products were authenticated effectively. The halftone image was similar to the carrier image, and the security of the anti-counterfeiting information was strong.FSIM values of extracted hidden information were all over 0.9, This showed that extraction effect of hidden information was superior and printed matter achieved the purpose of secondary anti-counterfeiting.The anti-counterfeiting method has dual anti-counterfeiting effects, and the anti-counterfeiting information has superior potential and extractability. It provides a new technical solution for the application research of packaging anti-counterfeiting.