基于混沌算法的数字图像加解密系统及Matlab仿真

发布时间：2018-11-19 11:24

【摘要】：近年来,随着计算机技术以及多媒体应用的飞速发展,各种各样的信息得以在网络上广泛传播,在信息传播越来越便捷的同时,随之而来的则是传播过程中所带来的各种安全问题,信息安全问题逐渐涉及到国家的政治、军事、经济以及文体教育等越来越多的领域。如果不能很好的解决这些问题,将会直接危及到国家的经济、金融、政治以及国防安全等一系列不稳定因素。在各种形式的信息传播方式中,图像信息是人们现如今获取信息的主要方式,自然而然数字图像信息传输的安全问题就成为信息安全方面的重中之重。由于数字图像本身具备的信息量庞大以及高冗余度等特点。所以在跟普通的文本数据相比较来说,一般的传统加密算法在对数字图像信息进行加密的过程中并不完全适合。同时,随着密码学的快速发展和计算机技术的不断完善,各种截获加密信息的方法也在不断改进,也使得一些传统的加密方法更容易被破解。所以信息获取者就需要使用更为安全的加密技术对存在的图像信息进行加密处理。本文主要研究如何提高数字图像在信息传播过程中的安全保密问题。由于混沌有着确定性、有界性、对开始的值的极端敏感性、长期不可估算性等良好的特性,使得混沌在图像数据的加密、通信的保密方面、计算机的图形处理、信号处理以及信号传输以及机械控制系统的优化等方向都有极其广泛的应用。本文在研究总结前人对混沌加密研究的基础上,在验证了 m序列作为图像加密密钥的各类优势的前提下,提出了一种基于m序列与logistic混沌映射相结合的新的图像加密算法。并通过Matlab对该算法进行了仿真实验,验证了它的可行性。并通过对加密效果的分析,证明了此种算法有较好的防攻击能力,在保密效果以及防护能力上要好于单独的m序列加密。
[Abstract]:In recent years, with the rapid development of computer technology and multimedia applications, all kinds of information can be widely spread on the network. The information security problems gradually involve more and more fields such as politics, military affairs, economy and cultural education. If these problems are not solved well, they will directly endanger the country's economic, financial, political and national defense security and a series of unstable factors. In various forms of information transmission, image information is the main way for people to obtain information nowadays. Naturally, the security of digital image information transmission becomes the most important aspect of information security. Digital image itself has the characteristics of huge amount of information and high redundancy. Therefore, compared with the common text data, the traditional encryption algorithm is not suitable for the encryption of digital image information. At the same time, with the rapid development of cryptography and the continuous improvement of computer technology, various methods of intercepting encrypted information are constantly improved, which makes some traditional encryption methods easier to be cracked. Therefore, information acquirers need to use more secure encryption technology to encrypt the existing image information. This paper focuses on how to improve the security and confidentiality of digital images in the process of information transmission. Because of its good properties such as certainty, boundedness, extreme sensitivity to the initial value, long-term inestimability and so on, chaos makes chaos in image data encryption, communication security, computer graphics processing, and so on. Signal processing, signal transmission and optimization of mechanical control system are widely used. On the basis of summarizing the previous researches on chaotic encryption and verifying the advantages of m sequences as image encryption keys, a new image encryption algorithm based on m sequence and logistic chaotic mapping is proposed in this paper. The feasibility of the algorithm is verified by Matlab simulation. Through the analysis of the encryption effect, it is proved that this algorithm has better anti-attack ability and is better than the single m-sequence encryption in the security effect and protection ability.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP309.7

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