基于位平面与混沌系统的图像置乱方法

Image scrambling based on bitplane decomposition and chaotic system

图像置乱作为信息加密重要手段之一随着网络技术的飞速发展得到广泛重视.混沌系统由于其伪随机性、非周期性和对参数及初值的敏感性而广泛应用于图像置乱,为增强图像性能,本文提出一种将位平面分解与混沌系统相结合的图像置乱方法.该方法将图像的各个位平面分别与混沌映射产生的混沌序列进行置乱,利用位平面提供的组合多样性组合得到加密图像.实验表明,该方法能得到良好的置乱效果和较强的抗攻击性能.另外,本文算法还具有密钥量大和算法扩展性好的优点.

Image scrambling, as one of the information encryption, has been attached great importance to with the development of network. Because of chaos system＇s sensitive for initial value, aperiodic and pseudorandom, it is widely applied for image encryption. A new image scrambling method based on bitplane-decomposition and chaotic system is presented in this paper. Firstly, the original image is decomposed into eight bitplanes. After this, several chaotic sequences are obtained through Logistic mapping, and by the chaotic system, the scrambling bitplanes are achieved. Then the scrambled bitplanes are combined as an encrypted image. Lastly, the experimental results show that the proposed algorithm is not only scrambled well, but also withdraws some hostile attacking. In addition to the above good properties of the algorithm, the other two merits are abundance encryption keys and its expansibility.