An Image Encryption Algorithm Based on Discrete Wavelet Transform and Two Dimension Cat Mapping

摘要

This article introduced a kind of method to produce two value sequences by separating the two-dimensional cat mapping sequence, according to the distribution of this two value sequence, establish exclusive corresponding relationships between the two-dimensional cat mapping chaos sequence and the discrete wavelet transformation coefficient matrix. The value of the discrete wavelet transformation coefficient matrix was encrypted and the scrambled by adjusting chaos sequence. The test result indicated that this algorithm can overcome the flaw of lower-dimensional chaos dynamics system easy to attack, and has the characteristics of highly secrecy, simple key, precise uniformity between restructuring image and original image. Meanwhile it can withstand the noise effect from the transmission process.