Research on image encryption algorithm based on hyper chaotic Lorenz system and wavelet transform

In this paper, a color image encryption algorithm based on hyper chaotic Lorenz system and discrete wavelet transform is proposed. The algorithm generates a chaotic sequence using a four-dimensional hyper chaotic Lorenz system and encrypts the image by combining with a two-dimensional Haar wavelet transform. The randomness and security of the image are effectively enhanced by wavelet decomposition, chaotic sequence encryption and bitwise dissimilarity operation. The experimental results show that the encrypted image has a uniform histogram, the information entropy is close to the ideal value of 8, and the correlation of adjacent pixels is significantly reduced, which can effectively resist the information entropy attack and correlation analysis attack. The algorithm performs well in terms of security, randomness and efficiency, and provides a reliable solution for the secure storage and transmission of image data.