基于2D-SFHM混沌系统和改进DNA编码的彩色图像加密

A Color Image Encryption Based on 2D⁃SFHM Chaos System and Improved DNA Encoding

为改善一维混沌系统密钥空间较小、安全性能较低而超混沌系统初始参数要求较高且效率较低等问题,提出了一种基于二维正弦函数超混沌映射(2D-SFHM)混沌系统和改进DNA编码的彩色图像加密方法。首先通过2D-SFHM混沌系统与Logistic系统生成混沌序列,将彩色图像分为RGB 3个通道,再基于混沌序列对每个通道分块进行DNA编码、解码、扩散和置乱,并在动态DNA编码的基础上提出基因突变机制,一定程度上丰富了DNA编码规则,最后合并3个通道得到彩色加密图像。实验结果表明,所提方法对密文图像直方图统计特性均匀平滑,相关性分析性能良好,实现了图像的安全加密效果,具有良好的加密性能和安全性。

A method for encrypting color images based on a two-dimensional sine function hyperchaotic map(2D-SFHM)chaotic system and improved DNA encoding is proposed to address the issues of small key space and low-security performance in one-dimensional chaotic systems,as well as the high initial parameter requirements and low efficiency in hyperchaotic system.Initially,chaotic sequences are generated using a 2D-SFHM chaotic system and Logistic system.The color image is then divided into RGB channels,and each channel is block-wise encoded,decoded,diffused,and scrambled based on the chaotic sequences and dynamic DNA encoding.Additionally,a gene mutation mechanism is introduced to enrich the DNA encoding rules.Finally,the encrypted color image is obtained by combining the three channels.Experimental results show that the proposed method achieves uniform and smooth statistical characteristics of the ciphertext image his-togram,good correlation analysis performance,and effectively secures the encrypted image,demonstrating excellent encryption performance and security.