【作者】 杨善超；

【导师】 龚声蓉；

【作者基本信息】 苏州大学 ， 计算机应用技术， 2006， 硕士

【摘要】 安全问题是当前网络多媒体应用中比较突出的问题,目前用于解决该问题的技术很多,其中的数字水印技术,尤其图像数字水印技术,以在版权保护方面的独特优势而引起人们的普遍重视,成为当前研究的热点。人类视觉系统理论在图像数字水印技术中有着非常重要的应用。进行水印嵌入时,充分利用人类视觉系统的视觉掩蔽特性,可以设计出感知性能良好的数字水印算法。从遭到破坏的图像中提取水印时,结合人的视觉特性进行受损水印的恢复同样能够收到较好的效果。本文结合人类视觉特性进行数字水印技术研究。通过分析前人的研究进展,结合可见水印特性,在小波域实现了一种具有图像内容保持特性的可见水印算法;利用水印冗余嵌入技术进行水印嵌入,根据水印遭破坏的情况进行水印提取,给出一种有意义水印的嵌入和提取方案;结合视觉冗余特性提出并实现了一种易于恢复的图像置乱算法和一种受损置乱图像的恢复方案;探讨了不规则区域的图像置乱方法,在此基础上,设计了一种置乱算法在数字水印算法中的应用框架;最后整合本文所提出的算法,实现了一个基于视觉特性的图像水印系统。更多还原

【Abstract】 Security is a very serious problem in the application of network and multimedia. To solve the problem, nowadays many technologies are considered, especially for image watermarking technology, which catches a wide attention for its unique advantages in copyright protection, and becomes the hotspot of current researches. Human vision system (HVS) theory is very important for image watermarking technology. Watermarking algorithm of good perception property can be designed by making full use of vision masking of HVS. When a watermark is extracted from a watermarked image that suffered attacks, better effect can be gained by reconstructing the watermark image based on vision characteristics. In the paper, the research of image watermarking is based on human vision characteristics. Firstly, by analyzing former researches and visible watermark characteristics, a visible watermarking algorithm with feature of holding image content is realized. Secondly, using redundant embedding technique to embed watermark and extracting watermark according to watermark content, a meaningful invisible watermarking scheme is proposed; Thirdly, combining with vision characteristics a resilient-prone scrambling algorithm and a restoring scheme of scrambled image with data loss are proposed, image scrambling technique of irregular region is discussed. Based on the proposed algorithms, a digital watermarking system scheme is designed. Moreover, an image watermarking system based on vision characteristics is realized by integrating the proposed algorithms. Experimental results show, the ideas that proposed in the paper is correct and the research is creative.更多还原