摘要： 提出了一种基于两个参数随机变换的混沌系统的伪随机序列发生器，生成一个随机性好、周期长的密钥序列并给出了统计特性分析的严格的理论证明。用此序列进行图像加解密实验，结果分析表明，提出的算法能够得到令人满意的加密效果。

关键词: 混沌；图像加密；一维线性映射；伪随机序列发生器

Abstract: This paper points out some existent problems in digital chaotic ciphers. A novel pseudo-random series generator based on a couple of chaotic system is presented. A chaos key stream with good randomcity and long period is made out, and its statistic character is proved strictly. The key stream has been used to encrypt image, and it is proved that method works perfect

Key words: Chaos; Image encryption; Piecewise linear chaos map; Pseudo-random series generator