数字图像水印算法与系统实现

【作者】 苟巍；

【导师】 李玉惠；

【作者基本信息】 昆明理工大学 ， 检测技术与自动化装置， 2012， 硕士

【摘要】 随着数字多媒体技术的发展和网络技术的不断普及,一方面使得越来越多的数字化产品不断地涌现,另一方面人们可以很方便的通过互联网进行无限制的上传、拷贝和下载数字资源。因此,如何能够更为有效的保护版权所有者的权利不受损害成为了一个亟需解决的课题。数字水印技术就是在这种背景下不断发展起来的。数字水印技术是信息隐藏技术的一个重要分支,它是通过将具有特定意义的符号或文字嵌入到数字产品中,并且水印信息在传播过程中不容易被擦除或破坏。当发生版权纠纷时,可以将提取出的水印作为侵权的证据,以此来证明产品的版权归属。近年来,数字水印技术已被广泛的应用于知识产权保护和信息安全等领域,并取得了显著的成效。目前,针对数字水印的算法比较多。采用空间域的算法,有运算速度快,能较快的嵌入和提取水印等优点,但是该水印鲁棒性较差；基于变换域的水印算法有较好的不可见性和鲁棒性,但是抗几何攻击的性能有待研究。本文采用小波变换(DWT)和奇异值分解(SVD)相结合的算法,来增强水印的鲁棒性和抗几何攻击能力。论文的工作如下：论文首先分析了数字水印技术发展现状、学习了数字水印的相关理论和性能评估标准。基于小波变换和奇异值分解方法和特点,进行了小波变换和奇异值相结合的数字水印算法研究；其次,分别对BMP和JPEG图像进行了数字水印处理和研究,实验表明小波奇异值算法较基于DWT的数字水印算法有较好的效果；再次,设计了一个基于Microsoft Visual C++6.0的数字水印软件,该软件具有水印嵌入、水印提取、图片质量评价等功能,使用简单,应用效果较好；最后,在FPGA开发平台上进行了算法的硬件化工作,完成了数字水印的硬件装置,使得该装置可以脱离PC机而独立运行。更多还原

【Abstract】 With the development of digital multimedia technology and the popularization of network technology, on the one hand, more and more consumer electronics constant ly emerging, on the other hand, People can easily unlimited upload, copy, and downloa d digital resources via the Internet. Therefore, how to more effective protection for c opyright holders are not undermined become an urgent need to address the issue. Di gital watermarking technology is the continuous development in this context.Digital watermarking information hiding technology is an important branch of, it is through will have specific meaning symbols or text into the digital products, an d watermarking information during the process of transmission is not easy to be era sed or destroyed. When there is a copyright issue, can will be extracted watermark as evidence of infringement, as evidence that a product of the copyright belongs to. In recent years, digital watermarking technology has been widely used in intellectu al property protection and information security and other fields, and have achieved r emarkable results.At present, there are a lot of algorithms for digital watermarking. For domain alg orithms, it can be faster to embed and extract watermark, but poor resistance to attack; t ransform domain-based watermarking algorithm has better invisibility and robustness, bu t there has more work to be studied against geometrical attacks. Combing the Wavele t transform (DWT) and Singular Value Decomposition (SVD) algorithm, the watermar k will has robustness and resistance to geometric attacks. The work of the paper is as fo Hows:This paper first analyzes the development status of the digital watermarking technol ogy and learns theory and performance evaluation standards for digital watermarking. It propose a improved method to combine the Wavelet transform and singular value ba sed on wavelet transform and singular value decomposition method and characteristic s; Secondly, Researching on digital watermarking and research with BMP and JPEG im ages, it experiments show that wavelet and the singular value decomposition algorith m has a good effect than DWT; Thirdly,Developing a digital watermark software b ased on the Microsoft Visual C++6.0, the software has the watermark embedding, water mark extraction, image quality evaluation and other funcations. it is easy to use and has better performance on application; Lastly, it has done hardware work on FPGA development platform for algorithm and achieve the design of the hardware device, whic h can run independently without PC.更多还原