Research On Image Encryption Technology Based On Seeded Chaos Generator And Propositional Logic Codin

In many application scenarios of digital communication,images are always an important carrier for people to complete information interaction.Due to the large amount of intuitive information contained in images,images have become the main object of sharing on social media and other network platforms.However,due to the vulnerability of images to external attacks during transmission,resulting in image disclosure and personal privacy damage,image encryption has become the focus of attention.Traditional image encryption algorithms are no longer suitable for images with complex data.The introduction of chaos theory provides new ideas and methods for image encryption.With the continuous development of chaotic encryption algorithms,the drawbacks of low security in low dimensional chaotic systems and high cost and complexity in high dimensional chaotic systems are gradually exposed.At the same time,the integration of chaos theory and other field theories has become an important means to improve the security of algorithms.Based on this,the main research content of this article is as follows:(1)To solve the problem of simple operation and low difficulty in deciphering a single low dimensional chaotic system,a seed chaotic generator is designed.When either Logistic map,Tent map,or Sine map are selected as inputs,six composite chaotic systems can be output.The chaotic performance of the output system was verified through Lyapunov exponent,bifurcation diagram,0-1 test,approximate entropy,and NIST test.The simulation results showed that the output system has a wider chaotic range,better randomness,and is more sensitive to initial values.(2)A chaotic image encryption algorithm based on propositional logic coding is proposed.Introducing propositions in the field of mathematics into the encoding and decoding of plaintext images,considering that propositional logic encoding is mainly performed on two adjacent bit planes,and that there is a strong correlation between adjacent bit planes,this algorithm completes the extraction and reorganization of plaintext pixel bit planes before encoding.Use the chaotic system output in(1)to perform XOR operations on the encoded image to obtain the final ciphertext image.Simulation analysis of ciphertext images shows that the scheme meets the standard for encrypting plaintext images,has sufficient key space,and can resist differential attacks and noise attacks.(3)A multi square nested and bidirectional localization diffusion algorithm is proposed.In order to reduce the correlation between adjacent pixels and improve the randomness of the diffusion process,two models for the scrambling and diffusion stages,multiple square nested and bidirectional positioning diffusion models,are designed based on the system outputted by the seed chaotic generator.The multi-square scrambling model is used to achieve intra block and inter block scrambling of the image,which changes the position of each pixel in the plaintext image.A new random diffusion strategy is studied,in which the scrambled intermediate ciphertext is divided into two parts,and the random diffusion of the intermediate ciphertext is accomplished using a chaotic system and a position matrix.Conduct security analysis on the obtained ciphertext image to verify whether the security of the algorithm is guaranteed.