A random decomposition method for chaotic sequences to improve the security of image encryption

Abstract The encryption efficiency of traditional encryption algorithms is relatively low, and they are no longer suitable for encrypting digital image information with large amounts of data and strong correlation. At present, encryption methods based on chaotic sequences can meet the demand for large amounts of image encryption data. However, the randomness of the chaotic sequences used in general chaotic encryption algorithms is strongly correlated with the initial state and parameters of the chaotic system, which may result in low complexity and chaotic degradation of the output sequence of the chaotic system. This paper proposes a sequence random decomposition algorithm that decomposes low complexity sequences into a large number of high complexity random decomposition sequences from the perspective of sequence decomposition. By using the sequence random decomposition algorithm to process the chaotic sequence output by the chaotic system, the random decomposition sequences with higher spectral entropy complexity were obtained. Finally, an image encryption communication system based on random sequence decomposition is constructed by combining random sequence decomposition with chaotic system. The security analysis of the image encryption communication system is carried out, and it is verified that the proposed system has better encryption performance.