基于像素差分的图像隐写算法研究毕业论文47p.docVIP

基于像素差分的图像隐写算法研究  摘 要 隐写术是一种隐藏通信手段，其目的是避开第三方的怀疑将信息传递出去，在军事、情报、国家安全等方面具有重要的意义。隐写的基本要求是要有极高的安全性和足够的信息嵌入量。隐写技术和隐写分析在国家军事、情报、商业等方面的意义重大。设计高度安全的隐写方法是一项十分紧迫的任务，而对隐写分析的研究同样很重要。一方面是要以尽可能隐蔽的方式将信息隐藏在载体信号之中，从而不引起对方的怀疑以实现隐蔽通信的目的；另一方面则是要以各种各样的手段检测隐蔽信息的存在，寻找敌对隐蔽通信的信源，从而阻断隐蔽通信的信道。如同密码分析和密码术之间的对立关系，隐写分析和隐写术之间如同展开了一场“军备竞赛，伴随着彼此的发展而演化前进。 由于当前针对隐写的主要对抗措施是利用统计分析手段发现数字媒体的统计异常性，因此统计隐蔽性是安全隐写的主要考虑因素。基于 LSB 的图像隐写方法简单，嵌入量较大；而基于人眼视觉特性的图像隐写算法具有很好的视觉隐蔽性和较大的嵌入量，因此两者都得到了广泛的应用，现在针对它们已经出现了多种有效的隐写分析方法。本论文对隐写和隐写分析的目的、基本原理、主要方法进行了讨论，对国内外研究现状进行了综述。系统地分析了现有的隐写算法，针对隐写算法中存在的统计异常，提出抗统计分析、安全性更好的算法，本文提出了一种结合了LSB与边缘匹配的基于像素差分的图像隐写算法，这些是上述算法中所没有提到的，预期希望可以实现兼顾嵌入秘密信息的容量和提高隐写图像的安全性的效果。 关键字：隐写分析；像素值差分；边缘匹配；最优像素调整 Abstract Steganographic methods is a kind of hidden communication, its purpose is to avoid the third party doubt information transfer out, in the military, intelligence, such as national security has an important significance. The basic requirement of implicit writing is to have a high safety and enough information embedded quantity. Steganographic techniques and steganalysis in the national military, intelligence, business etc is of great significance. The design of the high security steganographic method is a very urgent task, but to steganalysis also is very important. On the one hand is to as much as possible in a hidden way will information hiding in the carrier signal, thus not cause each others doubt to achieve the purpose of stealth communication; On the other hand is to all kinds of means testing the existence of hidden information, look for the enemy hidden communication source, thus blocking the concealed communication channel. As code analysis and cryptography confrontation relations, steganalysis and steganographic methods as launched a arms race, with each others development and evolution forward. Due to the current steganographic main countermeasures is the use of statistical analysis methods found that digital media statistical abnormality, so statistical disguised is safe hidden write mai