抗几何攻击的图像水印算法仿真研究

Image Watermarking Algorithm Against Geometric Attacks

研究图像水印传输安全问题。由于抵抗几何攻击一直是图像的数学水印技术研究热点,传统抗几何攻击的水印算法大多数只能抵抗简单的几何攻击,且水印的嵌入只是从空域或频域上单一进行,因此不能有效地抵抗几何攻击及其组合攻击对,导致图像处理攻击鲁棒性较差。为了提高图像水印抗几何攻击能力,提出一种采用空频域相结合的水印算法。在进行嵌入域选择时考虑到三基色(R、G、B)的特点,首先在B分量的空域中嵌入水印,提高水印的透明性;然后在G分量的频域中嵌入水印,提高水印的抗压缩性;最后通过调整量化参数和分块参数,灵活满足水印透明性和鲁棒性要求。仿真结果表明,提出的水印算法不仅能抵抗常规的图像处理攻击,而且可以有效地抵抗几何攻击及其组合攻击,可为产权保护提供有效手段。

Research on image watermark security problems.Resisting geometric attacks has been an one of image watermarking techniques,traditional resist geometric attacks of watermarking algorithm can resist most simple geometric attack,but can not resist complex geometric attacks effectively,which results in poor image attacks robustness.In order to raise the image watermark resist geometric attack power,this paper proposes a watermark algorithm combining space domain with frequency domain.When doing the choice in embedded domain,three colors（R,G,B） features are considered.First,in B component of the watermark,maximize watermark transparency;then in the G component of frequency domain,maximize watermark embedding watermarks resistance by adjusting the compressibility;finally quantitative parameters and block parameters are adjusted to flexibly satisfy the requirements of watermark transparency and robustness.Simulation results show that the proposed watermarking algorithm can not only resist conventional image attacks,but also effectively resist geometric attacks and their combination attacks,and is a very robust watermarking algorithm.