切延迟椭圆反射腔映射系统混沌序列的改进与彩色图像加密算法

TD-ERCS chaotic sequences' improvement and color image encryption algorithm

为了提高切延迟椭圆反射腔映射系统(TD-ERCS)的性能,实现对彩色图像信息的有效保护,提出了一种对TD-ERCS混沌序列的改进和基于该改进序列的彩色图像加密算法。分析与研究了TD-ERCS并加以改进,得到随机性能理想的四维混沌实值序列和二值序列;将彩色图像RGB三分量合成一图像后应用改进的TD-ERCS混沌序列以8×8分块置乱,从而加密图像。理论分析和实验结果表明,TD-ERCS改进序列性能更好;彩色图像加密算法密钥空间大,具有较好的加密效果和高的加密效率,并对统计分析具有较好的安全性和较强的抗JPEG压缩攻击能力。

To improve the performance of Tangent-Delay Ellipse Reflecting Cavity map System（TD-ERCS） and achieve effective protection of color image information,the authors proposed an improved algorithm for the TD-ERCS chaotic sequences and a color image encryption algorithm which was based on this improved sequences.The four-dimensional chaotic real sequences and binary sequences which had ideal random performance were obtained by improving the TD-ERCS.The image,which was composed of the RGB component of the color image,was scrambled by using the improved TD-ERCS chaotic sequences with 8×8 blocks,and then the image was encrypted.The theoretical analysis and experimental results show that the performances of improved TD-ERCS sequences are better than original sequences;the color image encryption algorithm has larger space of key,better encryption effect,higher encryption efficiency,and it also has better security to statistical analysis and stronger ability against JPEG compressing attacks.