论文标题
基于deneighborhood映射的图像脆弱的水印算法
Image Fragile Watermarking Algorithm Based on Deneighborhood Mapping
论文作者
论文摘要
为了解决固定偏移映射引起的安全风险以及图像水印中使用的随机映射的有限可恢复性，我们提出了一个基于deneighborhood映射的图像自动化脆弱的水印算法。首先，将图像分为几个2*2块，并根据图像块的平均值生成身份验证水印和恢复水印。然后，将DeNighborhood映射实现为对于每个图像块，其映射块被随机选择在其邻域之外，其大小由参数指定。最后，身份验证水印和恢复水印被嵌入图像块本身及其相应的映射块中。理论分析表明，在连续区域篡改的情况下，提出的水印方法可以比基于随机映射的方法获得更好的篡改图像块的恢复速率。实验结果验证了理论分析的合理性和有效性。此外，与基于随机映射，混乱映射和Arnold映射的现有嵌入算法相比，在连续区域篡改的情况下，所提出算法实现的篡改区域的平均回收率更高。
To address the security risk caused by fixed offset mapping and the limited recoverability of random mapping used in image watermarking, we propose an image self-embedding fragile watermarking algorithm based on deneighborhood mapping. First, the image is divided into several 2*2 blocks, and authentication watermark and recovery watermark are generated based on the average value of the image blocks. Then, the denighborhood mapping is implemented as, for each image block, its mapping block is randomly selected outside it's neighborhood whose size is specified by a parameter. Finally, the authentication watermark and the recovery watermark are embedded in the image block itself and its corresponding mapping block. Theoretical analysis indicates that in the case of continuous region tampering, the proposed watermarking method can achieve better the recovery rate of the tampered image block than the method based on the random mapping. The experimental results verify the rationality and effectiveness of the theoretical analysis. Moreover, compared with the existing embedding algorithms based on random mapping, chaos mapping and Arnold mapping, in the case of continuous region tampering, the average recovery rate of the tampered region achieved by the proposed algorithm is higher.
