基于离散小使用波变换的数字水印算法_毕业设计论文初版.doc

编号 论文 题目： 物联网工程 学院专业 年月 摘 要 ABSTRACT With the rapid development of network communication and broad appkication of multimedia techniligy,copyright protection of digital median work is becoming more and more important.Digital watermarking is viewed as an effective tool for copyright protection of multimedia data. Now algorithms based on DWT have many, including embedding watermark directly after DWT,combining two domains and so on.The algorithms based on DWT and SVD can take full account of characteristic of the multi-resolution of DWT and inherent factors of SVD.The characteristic of the multi-resolution of DWT can process an iamge at rated according to their important points,and the values of SVD is very robust.All which enhance the invisibility and robustness. At first the principle,typical algorithms and attack analysis of digital watermark is described.Then,a watermarking algorithm based on DWT is proposed.the watermark image is scrambled by a generalized Arnold transform so as to improve the security of the watermark;the watermark is embedded into the middle-frequency subband which guarantees the robustness of the algorithm;In order to implement the blind extraction,this paper improves an embedding algorithm based on HVS,which enhances the applicability of the algorithm.This paper tests the algorithm,and quantity of experiment data shows that algorithm has good robustness,and the imperceptibility of watermark can be guaranteed at the same time. Keywords: digital watermark；DWT；image scrambling；HVS 目 录 I ABSTRACT II 目 录 i 第1章 绪论 1 1.1选题背景及意义 1 1.2 数字水印概述 1 1.2.1数字水印的基本特征 2 1.2.2 数字水印的国内外研究现状 3 1.3本文的研究内容 3 第2章 数字图像水印算法与抗攻击性能分析 5 2.1 数字图像水印系统的基本模型 5 2.2水印攻击 6 2.3 水印的检测与评价 6 第3章 基于DWT-SVD分解的水印算法的设计 9 3.1小波变换的基本理论 9 3.1.1小波分析 9 3.1.2小波变换对信号的处理 10 3.2 基于DWT-SVD分解的水印嵌入算法 10 3.3 基于DWT-SVD分解的水印提取算法 13 第4章 Matlab仿真结果 15 4.1 仿真实验 15 4.2 抗攻击性能分析 18 4.3 小结 24 第5章 结论与展望 25 5.1结论 25 5.2不足之处及未来展望 25 参考文献 27 致 谢 28 附录A