The picture scrambling algorithms based on chaos are frequently used for images secure communications. In this paper

a new modified method of chaotic picture scrambling network is proposed by the chaotic mapping interval twice division and the chaotic orbits dynamic quantification. The new scrambling network adds the complexity and speeds up the computation of the network

since it overcomes the disadvantage that it need large number of computation to make the chaotic orbits ergods the whole chaotic mapping interval under the finite computational accuracy

reduces the computation. The paper also analyzed the time complexity and the scrambling performance of the new networks by computer experiments. The results show that this picture scrambling network has good scrambling capability and guarantees the security of the encrypted images effectively because it can work quickly with large cryptographic keys space.