针对伪随机数在数字图像加密中保密性不佳的缺点,提出了利用真随机数对数字图像像素序列进行异或的加密算法。加密前对原图像进行基于Arnold变换的图像分块置乱,在接收方进行异或解密、Arnold变换周期还原获得原图像,加密过程简单,图像置乱提高了保密性。经实验证明,加密后图像的像素相关性小,具有良好的抗剪切攻击和抗噪声性能。
According to true random number's disadvantage in digital image encryption,this article puts forward an encryption algorithm which yields XOR on digital image pixel sequence. This algorithm does image block scrambling based on Arnold transformation on the original picture before encryption. The receiver can get the original picture by doing XOR decryption and Arnold transformation. The encryption process of this algorithm is easy, what's more,image scrambling improves the confidentiality. Experiments prove that correlation among the pixels of the encrypted picture according to this algorithm is small, and this algorithm does well against scaling attack and has good anti-noise property.