Research On Key Technologies Of Optical Image Encryption And Authentication Based On Hyper-chaotic System

Through the research and design of encryption and decryption algorithms,image encryption technology can encrypt or hide effective information in the public network communication channel,so as to ensure the security of data and information.Optical image encryption and authentication technology has the advantages of large capacity,multidimensional,parallelism and high design freedom,which can meet the security needs of image transmission and management.It is one of the main implementation forms of the current image encryption technology,and the development of its key technologies has always received much attention.At present,in the field of optical image encryption and authentication technology,there are still sticking issues,such as the inconvenience of key distribution management in optical image encryption system,the low security of encryption method based on double random phase encoding technology,the problem of axis alignment in the process of optical implementation,and the crosstalk noise caused by superposition and multiplexing of multi-path image encryption.This paper focuses on the above-mentioned technical problems,and studies the key technologies of optical image encryption,watermarking,and authentication systems in the Fresnel transform domain and Gyrator transform domain to solve the existing problems.The main contributions of this paper are as follows:(1)In order to solve the problem of information security in the process of color image transmission,a method of color image encryption using vector operation and hyper-chaotic secondary image phase mask is proposed.Firstly,the original image vector is decomposed by using the principle of optical coherence superposition,and superimposed into two phase plates on the three channels of R,G and B.Then,a phase mask is used to encrypt one of the phase plates in Fresnel domain.Finally,the Kronecker product of two random matrices is used to further randomize the encoded image to realize multi-level encryption of color image.The one-time-pad encryption system designed in this study makes the algorithm well resistant to the attack of choice plaintext,Gaussian noise and statistical analysis,and greatly improve the security of traditional double random phase coding algorithm.(2)Aiming at the problem of secure transmission and distribution of complex keys in an optical image encryption system,combined with public key cryptography algorithms,an optical image encryption method based on hyper-chaos and compressed sensing is proposed.Firstly,a single-pixel imaging system is used to sample and measure the original image through the Walsh-Hadamard transformation and measurement matrix.The sparse operation makes the energy more concentrated and provides conditions for subsequent compression.The binary Hadamard matrix is easy to be realized and generated on high-speed spatial light modulation devices.Then,Chen 4D hyper-chaotic system is used to construct the corresponding hyper-chaotic sequence,preprocess to obtain the hyper-chaotic random phase mask to be used.By using the hyper-chaos phase mask in Fresnel domain of the image to be encrypted,the original image is encoded with double random phases.Next,the image is further encoded by DNA sequence operation.Finally,the asymmetric management of the key sequence is realized by using the public key cryptosystem.The research aims to improve the security of the double random phase encoding system in the Fresnel domain,enhance the key sensitivity,and reduce the time complexity of public-key cryptography encryption algorithms.The results show that the proposed method has good statistical distribution characteristics and strong resistance to environmental interference.(3)Aiming at the problem of axis alignment in the watermark encryption algorithm during optical implementation and the security of the optical cryptosystem,an optical watermarking method based on hyper-chaotic phase mask and Gyrator transform is proposed.First construct a hyper-chaotic phase mask using the Chen 4D hyper-chaotic system.Then,the hyper-chaotic phase plate is illuminated by the vortex light constructed by the Fresnel zone plate and the radial Hilbert mask.Finally,the encrypted watermark image is implanted into the host gray image with the help of Gyrator transformation to achieve the optical information hiding in the Gyrator domain.The embedded watermark information in the target image is extracted by the Gyrator inverse transform,and the Fresnel zone plate can effectively reduce the impact of axial error on the decryption effect and improve the quality of the extracted watermark image.This method can properly solve the problem of axis alignment,and extract high-quality watermark information from the high imperceptible target image.The encrypted target image has high signal-to-noise ratio and strong correlation with the host image.It can effectively resist strong salt and pepper noise attacks and Gaussian noise attacks,and has good robustness against occlusion attacks,effectively improving system security.(4)Aiming at the crosstalk noise in multiplex image and the information security problem in different authentication levels,an optical multi image authentication method based on hyper-chaotic amplitude mask and phase information multiplexing in Gyrator transform domain is proposed.Firstly,He-fractional order hyper-chaos system is used to construct the random amplitude mask of hyper-chaos.Then the original image is encoded by the improved gerchberg Saxton algorithm at low or high level,and the hyper-chaotic mask is used as the amplitude constraint to obtain the target image iteratively,and the N target images are encoded into the composite image.Finally,the composite image is transformed into two simple phase masks by Gerchberg-Saxton iteration.The research results enable users with different security levels to have their own authentication keys.In low-level authentication,the non-linear correlation peaks between the authentication image and the original image can be used to determine the correctness of the authentication results.High-level authentication can obtain an authentication image with a high similarity to the original image.The proposed method has good robustness against occlusion attacks and noise attacks,and solves the problem of crosstalk noise caused by multi-channel image overlay and reuse in optical multiimage authentication and encryption methods,which improves the security of optical authentication systems.For all the above research contents,the paper uses system design and numerical simulation to confirm.By analyzing the optical image transmission environment,designing simulated attack methods,and combining the algorithms and systems,the security of the optical image encryption and authentication system is enhanced.The experiments verify the advancedness of the algorithms and systems in terms of feasibility,robustness,security,and time complexity,which have played a good role in promoting the further development of optical information security systems.