Standard映射及其三维扩展在多媒体加密中的应用

混沌映射因为初值敏感性、参数敏感性、遍历性和类随机性的特点,很适合用于信息加密.离散化后的混沌映射与扩散机构相结合,与传统的密码算法相比,加解密速度更快,能够满足实时性要求.与Baker和Cat映射相比,Standard映射具有更大的密钥空间,更适合于信息加密.因此将其扩展到三维空间,构造了基于离散Standard映射的多媒体加密方案,分析了Standard映射的参数敏感性,给出了置乱循环次数和扩散函数的选择方法.实验结果表明,算法具有较高的安全性和较快的加解密速度,适合于多媒体数据,如图像、视频、多波段图像等的加密.

Applications of standard map and its 3-D extention in multimedia encryption

Based on the features of initial value sensitivity, parameter sensitivity, ergodicity and random similarity, chaotic maps are now widely used in information encryption. The encryption method combining discretized 2 D chaotic maps with spreading functions has faster encryption speed than traditional algorithms. Compared to Baker map and Cat map, Standard map has larger key space, which makes it more suitable for information encryption. In this paper, Standard map is extended to 3 D space and a multimedia encryption scheme based on it is proposed. What's more, the parameter sensitivity of Standard map is analyzed, and the methods to select suitable spreading function and loop times are also proposed. Experiments show that, the algorithm is of high security and is faster than DES, which makes it suitable for multimedia encryption such as image, video, multispectral image and so on.