数字水印是信息隐藏技术的一个重要方向,它在版权保护和认证等方面应用的非常广泛。正因为此,水印对攻击具有鲁棒性是很重要的。本文首先介绍水印技术现状及其安全方面的一些研究,然后详细研究图像水印中的几何不变性水印。并着重研究基于不变矩的不变水印以及图像归一化技术。其中,本文所针对的对水印的攻击是几何攻击,包括缩放、翻转和旋转等基本的几何操作。
Digital watermarking is an important direction of information hiding, which is widely used in copyright protection and authentication. That is why the watermark is robust against attacks is very important. This paper first introduces the status quo and security research of watermarking technology, then a detailed study of the geometric invariant watermark. And focus on moment invariants based on the same watermark and image normalization techniques. In this paper, the attacks on image are geometrical attacks, including Flipping, Scale and Rotation.