【作者】 路陈红；

【导师】 张敏瑞；

【作者基本信息】 西安科技大学 ， 通信与信息系统， 2003， 硕士

【摘要】 数字图像水印算法是数字水印技术的一个研究热点。本文介绍了数字图像水印技术，讨论了数字图像水印系统各部分内容，分析了数字图像水印各种典型算法的优缺点，提出了两种不同应用的倒谱域图像水印新算法：一维倒谱变换图像水印算法，二维倒谱域扩展频谱图像水印算法。 第一种算法可用于版权标识，与先前算法相比，它在JPEG压缩、图像剪切、拉伸、加噪等方面抗攻击能力得到了提高，该算法在水印提取时需要原始图像。第二种算法可用于非法源跟踪，它将倒谱特性与扩频通信理论相结合，水印提取时只需要密钥而不需要原始图像。 作者采用不同图像对提出的两种新算法进行了大量的计算机模拟实验，仿真结果表明所提算法对JPEG压缩、滤波等多种攻击均具有较强的鲁棒性。更多还原

【Abstract】 Digital image watermarking algorithms are one of the investigation hotspots in the digital watermarking techniques. This thesis is concerned with digital image watermarking technology. The components of a digital image watermarking system are discussed in detail. Advantages and disadvantages of various typical algorithms are analysed. Two novel image watermarking algorithms in cepstrum domain for different applications are presented, namely 1-dimension cepstrum transformation image watermarking algorithm and 2-dimension cepstrum domain spread spectrum image watermarking algorithm.The first method, used for copyright protection, demonstrates improved robustness against JPEG compression, image cropping, scaling, noising, and so on in comparison to existing algorithms. The original image is needed to extract the watermarking signal. The second approach used for traitor tracing, combines cepstrum features with spread spectrum theory. No original image but the key is required for watermarking extraction.The performance of the proposed algorithms is evaluated through extensive computer simulations using various different images. Simulation results show that the proposed algorithms are robust against most watermarking attacks such as JPEG compression, image filtering and so forth.更多还原