Ramos Andy M, Artiles José A P, Chaves Daniel P B, Pimentel Cecilio
Department of Electronics and Systems, Federal University of Pernambuco, Recife 50740-550, Brazil.
Entropy (Basel). 2023 Mar 16;25(3):508. doi: 10.3390/e25030508.
With the rapid development of digital signal processing tools, image contents can be easily manipulated or maliciously tampered with. Fragile watermarking has been largely used for content authentication purposes. This article presents a new proposal for image fragile watermarking algorithms for tamper detection and image recovery. The watermarked bits are obtained from the parity bits of an error-correcting code whose message is formed from a binary chaotic sequence (generated from a secret key known to all legitimate users) and from bits of the original image. Part of the codeword (the chaotic bits) is perfectly known to these users during the extraction phase, adding security and robustness to the watermarking method. The watermarked bits are inserted at specific sub-bands of the discrete wavelet transform of the original image and are used as authentication bits for the tamper detection process. The imperceptibility, detection, and recovery of this algorithm are tested for various common attacks over digital images. The proposed algorithm is analyzed for both grayscale and colored images. Comparison results reveal that the proposed technique performs better than some existing methods.
随着数字信号处理工具的快速发展，图像内容可以很容易地被操纵或恶意篡改。脆弱水印已大量用于内容认证目的。本文提出了一种用于图像脆弱水印算法的新方案，用于篡改检测和图像恢复。水印位从纠错码的奇偶校验位获得，其消息由二进制混沌序列（由所有合法用户都知道的秘密密钥生成）和原始图像的位组成。在提取阶段，这些用户完全知道部分码字（混沌位），从而为水印方法增加了安全性和鲁棒性。水印位被插入到原始图像离散小波变换的特定子带中，并用作篡改检测过程的认证位。针对数字图像的各种常见攻击，测试了该算法的不可感知性、检测和恢复能力。对所提出的算法进行了灰度图像和彩色图像的分析。比较结果表明，所提出的技术比一些现有方法表现更好。
