基于线性同余的伪随机序列图像加密

Image Encryption Through Pseudo-Random Sequence Based on Linear Congruence

为了进行保密通信,需要对图像进行加密,采用了一种基于线性同余的序列加密方法。提出了一种基于24比特的线性同余随机序列发生器y(n+1)=(32719*y(n))mod(16777213),通过独立性和均匀性检验证明了发生器产生的序列的随机性。将初始值作为密钥,产生伪随机序列,与图像像素通过异或加解密。描述了基于该线性同余随机序列的图像加解密算法。图像加密解密实验表明,序列具有参数敏感性。所提出的线性同余随机序列发生器能够正确产生伪随机序列,可以用于最大像素为2896×2896的图像加解密通信。

In order to encrypt communication, sequence cipher in linear congruence was used to image secttrity. The pseudo - random sequence generator in 24 bits based on linear congruence such as y （ n ＋ 1 ） = （32719 ＊ y （ n ） ） mod （ 16777213 ） was studied. The randomicity of sequences from the generator was verified through independence and uniformity. The images were encrypted and decrypted through exclusive OR algorithm of images and pseudo - random sequence coming from initial security key. The algorithm for encrypting images through sequences from linear congruence generator was described. The images encrypting and images decrypting show that the sequences are sensitive to initial parameter. The generator can produce pseudo- random sequence, and can be used to encrypt inages with maximum picture pixel.