基于压缩感知和变参数混沌映射的图像加密

为了减少加密图像的存储和传输负担,提出基于压缩感知(CS)和变参数控制混沌映射的图像加密算法。算法采用变参数控制混沌映射产生的测量矩阵对图像进行观测,选用与测量矩阵非相干的离散余弦变换(DCT)矩阵为稀疏基矩阵,使得压缩和加密同时完成。为了进一步提高加密算法的安全性,引入扰动因子使得加密算法的密钥与明文相关。同时,加密系统具有抗差分攻击的能力。另外,执行耦合的置乱扩散操作,使得置乱和扩散同时完成,更进一步增强了系统的安全性。加密图像的每个像素以8bit整型的形式输出便于数据的存储、显示和传输。实验结果表明,本文的加密算法是有效的和安全的。

Image encryption based on compressive sensing and variable-parameter chaotic mapping

To reduce the burden of storage and tr ansmission of encrypted images,an image encryption algorithm combining compressi ve sensing with variable-parameter chaotic mapping is proposed.In this algorith m,both the compression and encryption of an image can be achieved simultaneously.In the pr ocess of compressive sensing, the measurement matrix is generated by variable-parameter chaotic mapping and d iscrete cosine transform (DCT) m atrix is selected as sparse basis matrix which is incoherent with the measurement matrix.To further strengthen th e security of the encryption scheme,a disturbance factor is introduced to make the cipher keys and the plain -text correlated.Meanwhile,the encryption algorithm possesses the ability to resist different attacks with depe ndent scrambling and diffusion operations.Each pixel of the encrypted images is encoded with 8bits to facilit ate storage,display and transmission. Experimental results demonstrate that the proposed encryption algorithm is feas ible,effective and secure.