The Research of Image Encryption Algorithm Based on Hyper-chaotic Chen System Integration with Time Delay
Li Sun · Science Technology and Engineering · 2013
Time delay was a widespread phenomenon in nature,the phenomenon of time delay was also existed during the generation of pseudo-random sequence in the image encryption. This system was very suitable for this field due to the characteristics such as the good randomness,difficult to prediction and analyze of the track and complex. However,the phenomenon of time delay was not considered by the researchers when they used the chaotic or hyper-chaotic system to encrypt the image,resulting in the non-ideal autocorrelation of the pseudo-random sequence and the misadventure performance of encryption. Therefore,a new image encryption algorithm based on the hyper-chaotic Chen system integration with time delay to solve this problem. The time delay was introduced into the chaotic sequence generated by hyper-chaotic Chen system to obtain the hyper-chaotic pseudo-random sequence on the time delay; the permutation method of position index was used to permute the row and column of the pseudorandom sequence on the time delay to get a new group pseudo-random sequence,and used it to permute the image; Finally,the key stream sequence was used to treat the new pseudo-random sequence and the diffusion function to encrypt image. The MATLAB simulation software was used to validate the method proposed,the results show that the image encryption algorithm had better encryption performance,the key space is larger,the anti-plaintext attack property was greatly enhanced,and the variation of autocorrelation of chaotic sequence was smaller.