College of Artificial Intelligence, Nanchang Institute of Science and Technology, Nanchang 330108, China.
School of Electronic Information, Wuhan University, Wuhan 430072, China.
Sensors (Basel). 2022 Apr 28;22(9):3394. doi: 10.3390/s22093394.
Print matter authentication based on anti-counterfeiting techniques has received continuously increasing concern from academia and industry. However, the existing printing anti-counterfeiting solutions often have the defects of poor identification experience, high cost, or weak anti-counterfeiting ability, and cannot achieve pre-sale anti-counterfeiting. Therefore, a novel steganography-based pattern for print matter anti-counterfeiting by smartphone cameras is proposed in this study. Firstly, every pixel in the original binary message image (such as QR code) is replaced by a square pixel block with the same binary gray value of 0 or 255 (the first-level expansion). Secondly, the obtained image is encrypted based on the logistic chaotic sequence, and then scrambled by Arnold transform. Lastly, once again every pixel in the generated image is replaced with a square pixel block (the second-level expansion), the size and gray value of which can be set to control the semi-fragile ability to distinguish an originally printed pattern from its illegitimate copy. If the message extracted from the printed pattern through the inverse procedure is complete enough to decode and read, the pattern is assumed to be an original print. Experimental results verify the advancement and effectiveness of the proposed scheme in distinguishing the copied pattern.
基于防伪技术的印刷品认证受到了学术界和工业界的持续关注。然而，现有的印刷防伪解决方案通常存在识别体验差、成本高或防伪能力弱、无法实现售前防伪等缺陷。因此，本研究提出了一种基于智能手机摄像头的新型印刷品防伪隐写术模式。首先，原始二值消息图像（如 QR 码）中的每个像素都被替换为具有相同二进制灰度值 0 或 255 的正方形像素块（一级扩展）。其次，根据 logistic 混沌序列对所得图像进行加密，然后通过 Arnold 变换进行置乱。最后，再次将生成图像中的每个像素替换为正方形像素块（二级扩展），其大小和灰度值可设置为控制区分原始打印图案与其非法副本的半脆弱能力。如果通过逆过程从打印图案中提取的消息足以解码和读取，则认为该图案是原始打印。实验结果验证了所提出方案在区分复制图案方面的先进性和有效性。
