基于分数阶Chen超混沌系统和压缩感知的可视化图像加密算法

Visual Image Encryption Algorithm Based on Fractional-order Chen Hyperchaotic System and Compressive Sensing

本文基于分数阶Chen超混沌系统,压缩感知以及伯恩斯坦多项式嵌入提出了一具有视觉意义的图像加密算法,其旨在同时实现对图像数据和图像外形的双重保护.整个的加密过程主要由预加密和嵌入这两个阶段组成.在预加密阶段,首先利用Arnold置乱和由改进型Sine映射所产生的受控测量矩阵对明文图像的小波系数进行加密和压缩.接着再将加密数据线性量化到0到255之间以产生类噪声秘密图像.同时为了降低遭到攻击的可能性,在嵌入阶段中,本文采用伯恩斯坦多项式嵌入将类噪声秘密图像隐藏到某一可公开获取的载体图像中以生成具有视觉意义的密文图像.另外,明文特征值用于生成加密过程中的密码流,从而提高了加密算法抵抗明文攻击的能力.最后,仿真实验和安全性分析表明本文提出的加密算法是有效的,同时具有很好的视觉安全性和解密质量.

In this paper,a visually meaningful image encryption algorithm is proposed based on the fractional-order Chen hyperchaotic system,compressive sensing and Bernstein polynomial embedding,which aims to simuitaneously achieve double protection of image data and image appearance.The entire encryption process is mainly composed of two stages:pre-encryption and embedding.In the pre-encryption stage,first,the wavelet coefficients of the plain image are encrypted and compressed via the Arnold confusion and the key-controlled measurement matrix generated by the improved Sine map.Next,the encrypted data is linearly quantized between 0 and 255 to generate a noise-like secret image.Meanwhile,to reduce the possibility of being attacked,in the embedding stage,Bernstein polynomial embedding is adopted to hide the noise-like secret image in a publicly available carrier image to generate a visually meaningful cipher image.Additionally,the plaintext eigenvalue is utilized to generate the keystream in the encryption process,thereby improving the ability of the encryption algorithm to withstand the plaintext attacks.Finally,simulation experiments and security analysis indicate that the proposed encryption algorithm is effective,and has good visual security and decryption quality.