基于隐写术的隐蔽保密通信系统设计理论与关键技术

项目名称： 基于隐写术的隐蔽保密通信系统设计理论与关键技术

项目编号： No.60803155

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 张卫明

作者单位： 中国人民解放军信息工程大学

项目金额： 18万元

中文摘要： 隐写术是关于如何将秘密消息嵌入到多媒体数据中进行隐蔽通信的技术。本项目研究影响隐写效率和安全的核心编码问题，并在此基础上利用隐写术自身特性,设计同时具有隐蔽性和保密性的通信方案。在以下五个方面取得了一系列成果。 1) 提高嵌入效率是隐写设计的关键，本项目得到了可快速实现并接近嵌入效率理论上界的二元隐写码，然后组合多层二元隐写码构造了接近最优的加减1和加减2隐写编码。这一方法被同行以作者姓氏命名为"ZZW构造"。 2) 进一步，我们将ZZW构造推广到了湿纸模型和湿度级模型下，分别得到了可接近嵌入效率上界的编码方法，并且计算复杂度较之已有方法更低。 3) 本项目利用隐写信息的难提取性开发保密性来研究"加密隐写联合编码"问题。在信息论模型下度量难提取性的强度，分析了影响隐写码密钥疑义度和消息疑义度的因素。 4) 利用隐写码，对多种载体设计了安全隐写算法。为分析隐写算法的安全强度，研究了图像隐写检测方法，并对多种隐写算法和工具研究了隐写信息提取方法。 5) 对二元载体，提出了可达率失真界的可逆隐藏编码方法，该方法构建了可逆隐藏与信源编码之间的一致关系。

中文关键词： 信息隐藏；隐写术；隐写编码；嵌入效率；保密性

英文摘要： The purpose of steganography is to send secret messages by embedding them into some multimedia data. This project studied the key coding problem about the steganographic efficiency and security, and designed communication schemes with privacy and concealment based on the property of steganography itself. We got a series of results in following five aspects. 1) How to improve the embedding efficiency is pivotal for steganographic coding. We proposed fast binary steganographic codes which can approach the theoretic upper bound of embedding efficiency, and constructed near-optimal codes for plus-minus 1 or 2 steganography. This method is dubbed "ZZW construction" after its authors. 2) Furthermore, we generalized ZZW construction to wet paper model and wet-scale model, and proposed codes approaching the upper bound of embedding efficiency with lower computational complexity than previous methods. 3) This project researched joint coding of cryptography and steganography by exploiting privacy from the difficulty of extracting hidden information. We defined measurements for the privacy provided by the difficulty of extraction in information theory model, and analyzed the ingredients that influence the key equivocation and message equivocation of steganographic codes. 4) Based on steganographic codes, we proposed security steganographic schemes for various of covers. To analyze the security of steganography, we also studied steganalysis methods for image covers, and exploited extracting methods for several steganographic algorithms and tools. 5) For binary covers, we proposed reversible data hiding codes approaching the rate-distortion bound, which established the equivalence between reversible data hiding and source coding.

英文关键词： information hiding; steganography; steganographic coding; embedding efficiency; privacy