Research On Multiple-image Compression And Encryption Based On Optical Chaos

In recent years,big data and artificial intelligence have entered people's lives.Massive data information has been widely distributed in computer network systems around the world,such as text,images,audio,and video.Its security is similar to that of individuals,groups,and even countries.Color images have special colors and shapes,and the information contained in them is far more intuitive than sound.People prefer to use images for information transmission and expression.It has also become the most widely used and most important form of information expression.Its application areas involve politics,economy,education,entertainment,etc.In some special research fields such as military,medical,and legal,there is often information that does not want to view sensitive images,especially unauthorized third parties.The leakage,forgery,and tampering of sensitive image information will not only damage the vital interests and personal privacy of the people,but also cause huge losses to the production and life of enterprises and society,and even endanger national security.Therefore,ensuring the security of image information has become a real problem urgently needed to be solved in today's society,attracting the attention of all walks of life in society,and it is a hot topic that scholars at home and abroad are scrambling to study.With the maturity of chaos theory,researchers have found that the initial value sensitivity,quasi-randomness,and complex nonlinear dynamic behavior of chaos have natural characteristics of information hiding and unpredictability.The application of chaos technology in the field of image encryption has unique advantages.Compared with the traditional electrical chaotic systems,the vertical-cavity surface-emitting laser(VCSEL)as the most commonly used semiconductor laser,light chaos produced by its can break through the bottleneck of thr chaos of electricity limit,has faster speed,greater bandwidth,lower loss,and higher complexity.The outstanding characteristics of optical chaos make it have great advantages and broad application prospects in the field of image information encryption.Therefore,a multiple-image compression and encryption algorithm is studied in this paper.The main research contents are as shown below:First,this paper designs a secure communication system that generates optical chaos based on two mutually coupled VCSELs.The external disturbance conditions in this system are mutual injection.By changing the two parameters of injection intensity and injection time,So that the two lasers reach a synchronized state,and the output optical signal is in a chaotic state,which is used to generate image encryption and decryption key.The theoretical foundations of the respective processes are first introduced,and then the good nonlinearity and synchronization characteristics of the two VCSELs are simulated on this basis,and their performance is demonstrated by parameter indicators such as time series,power spectrum,phase diagram,and cross-correlation function.Then,this paper proposes a multiple-color image compression and encryption system.The optical chaos generated by the above-mentioned mutual coupling laser chaos system is first used to generate the encryption and decryption keys used in the image encryption process.At the same time,before implementing image encryption,in order to reduce the amount of transmitted data,this paper introduces a compressive sensing technology based on discrete wavelet transform(DWT).Firstly,two-color images are decomposed into their respective RGB images,and compressive sensing is performed respectively.Then,a double random phase mask image encryption based on fractional Fourier transform(FrFT)is performed,and then the equal modulus decomposition(EMD)is performed to realize asymmetric encryption.This method can not only achieve multipleimage encryption with a small amount of data but also prevent information leakage.Finally,numerical simulations of parameters such as peak signal-to-noise ratio,mean square error,histogram,and pixel correlation verify the feasibility and effectiveness of the system.The research of this paper has broad practical significance for the application of optical chaos in image encryption.