提出了一种基于四值混沌阵列的数字图像加密算法。利用混沌系统产生一个和图像大小相同的四值伪随机混沌阵列。加密时，将混沌阵列中不同的值分开处理，对不同的值对应的图像点像素进行不同的加密，然后根据给定的随机整数在混沌阵列中寻找加密结果的存放位置。解密是加密的逆过程。实验和分析结果表明，算法的时间复杂度和空间复杂度较低，加密效果较好，安全性较高。

This paper presents a digital image encryption algorithm based on four-value chaotic array. It uses chaotic maps to generate a four-value chaotic array whose size is as big as the image. In encryption processing, we deal with the different value in the chaotic array separately, and use different keys to encrypt pixels which correspond to different chaotic array value respectively and then put the result to the appropriate position in the chaotic array according to the given random integers. Decryption is the converse of encryption. The analysis and the results of experiments show that the scheme has low time complexity, low space complexity and good security.