In order to solve the contradiction between imperceptibility and robustness of traditional robust watermarking technology, the spatial domain zero watermarking technology is researched and the effect of the numerical relationship between the overall mean of all selected blocks and block mean against common image processing attacks is analyzed. The results show that the numerical relationship has strong stability. Based on this, a new zero watermarking scheme with strong robustness in the spatial domain is proposed. Firstly, using the characteristic of sensitivity to initial value, logistic mapping is used to find the position of image block and the original copyright information is pre-processed by chaotic encryption and Arnold scrambling technologies. Secondly, the stability of the numerical relationship between the overall mean of all selected blocks and block mean is utilized to generate feature information. Finally, the generated zero watermarking signal is post-processed again by chaotic encryption and Arnold scrambling technologies. Experimental results on a large number of standard test images show that the proposed algorithm has strong robustness against common image processing, scaling, rotation, and various combination attacks. Compared with similar robust zero watermarking schemes, the proposed scheme not only saves 90 % running time but also improves robustness performance by 15 % on average. These results show that it has lower computational complexity and better performance and can be applied in copyright protection applications for high quality requirements of cover images.%为了解决传统鲁棒水印技术不可感知性和鲁棒性间的矛盾,对空域零水印技术进行研究,分析了常规图像处理攻击对载体图像所有选择分块整体均值与分块均值间大小关系的影响,结果表明此关系具有较强的稳健性.基于此,提出了一种新的空域强鲁棒零水印方案.1) 利用混沌系统对初值敏感的特性映射图像分块的位置和采用混沌加密与Arnold 空间置乱技术对原始水印信号进行预处理;2) 采用载体图像所有选择分块整体均值与分块均值间大小关系的稳健性能来构造特征信息;3)采用混沌加密和Arnold 空间置乱技术对生成的零水印信号进行后处理.仿真实验结果表明,本文算法对常规的图像处理、尺寸缩放、旋转和多种组合攻击等都表现出较强的抗攻击能力.与相似的鲁棒零水印方案相比,本文算法的平均运行时间不仅减少了约90 %,而且抗攻击平均性能提高了约15 %,表明它具有较低的计算复杂度和更优越的鲁棒性能,适用于对载体图像质量要求较高的作品版权保护应用场合.
展开▼
