Research On The Security Of Image Encryption Algorithm Of Reversible Data Hiding In Encrypted Images

With the rapid development of the Internet and the spread of cloud storage,people can more conveniently store,access and transmit Internet information,including text,images,voice,video and other information.The user encrypts the image and uploads it to the cloud,the cloud server then embeds the relevant information into the ciphertext image for easy management.This thesis studies the problem of the low security of the existing reversible information hiding algorithm in encrypted images.The main work is as follows:Aiming at the problem that the security of XOR encryption and scrambling encryption algorithms commonly used in reversible information hiding of encrypted images is not high,a more secure encryption algorithm based on block scrambling modular addition is designed.comparing and analyzing the security of XOR encryption,scrambling encryption,block xor scrambling encryption proposed by Huang,and the block scrambling modular addition encryption algorithm proposed in this thesis by analyzing the histogram and difference histogram of the encrypted image,and using known plaintext attacks and ciphertext attacks.The experimental results show that scrambling encryption has the risk of leaking pixel value information,and can not resist the known plaintext attack;XOR encryption has the risk of leaking pixel location,and can not resist ciphertext attack;Huang's encryption algorithm has the risk of the difference histogram leaking pixel information,and can not resist the ciphertext attack.However,the block scrambling modular addition encryption proposed in this thesis not only does not have the risk of pixel information leakage,but also can resist the known plaintext attack,moreover,the encrypted image has low pixel redundancy and can resist ciphertext attacks.Finally,the reasons for the experimental simulation results are analyzed in detail,and the safety analysis results are summarized.The improved encryption algorithms are more secure than scrambling encryption,XOR encryption,and Huang's encryption algorithms.The ciphertext image generated by the commonly used XOR encryption,scrambling encryption and some encryption algorithms combined with XOR and scrambling is a disorganized noise image,which is easy to attract the attention of attackers.In order to solve this problem,this thesis introduces an image encryption algorithm based on image camouflage proposed by Zhang,and proposes an improved algorithm for the problem that the converted image quality is not high.The experimental results show that the improved image obtained by the improved algorithm has higher similarity to the target image and higher quality than the converted image obtained by the Zhang algorithm.Finally,a GUI algorithm simulation system was produced to demonstrate the algorithm more intuitively.