Research On Quantum Image Encryption Algorithm Based On Bit Plane Decomposition And Chaotic System

Due to the rapid progress of quantum computing and quantum informationtechnology,traditional image encryption technology can no longer meet the increasing security needs of today’s society.Therefore,many scholars begin to focus on quantum image encryption.Compared with classical image encryption,quantum image encryption has many characteristics that classical image encryptiondoes not have,such as quantum unpredictability,quantum parallelism and theoretical absolute security.These characteristics make quantum image encryption have excellent expected effects.However,the general quantum image encryptionalgorithm can achieve the encryption effect,but it requires more quantum bits,high computational complexity,and insufficient key space,so the encryption effect and security can not be guaranteed.This paper designs two kinds of quantum color image encryption algorithm based on quantum computation,quantum image representation,chaotic system and bit plane decomposition,and makes experimental simulation and analysis.The main contents are as follows:(1)In order to save quantum resources and improve the encryption efficiency,a quantum color image encryption algorithm based on bit plane decomposition is presented.It can effectively utilize quantum resources and greatly improve the encryption effect.The quantum representation model selected by the algorithm is a QRCI model that contains color information,location information and bit plane information.A quantum bit exchange operation is designed by using quantum exchange gate,which is used in color images to scramble the image pixels and exchange the color channels.Secondly,the bit plane sequence is reversed,which further enhances the scrambling effect with the Arnold transformation.Then,the image is decomposed into eight layers by bitplane,and the initial value of the six-dimensional hyperchaotic system is determined by the hash value generated by the SHA-256 algorithm.Finally,using the chaotic sequence generated by the system,the image information is diffused to complete theentire encryption process and form an encrypted image.Numerical analysis shows that compared with previous encryption algorithm,this algorithm greatly reduces the number of quantum bits required for color image storage and has a higher sensitivity.The simulation results show that the scheme has good encryption performance and can withstand most common attacks.(2)In order to expand the key space and improve the security of the encryption algorithm,a quantum color image encryption algorithm based on chaotic system is presented.First,the original image is divided into three gray-scale images according to red,green and blue(RGB).A new enhanced quantum image representation(NEQR)is used to store each image information.Next,the correlation between the image pixels is reduced by using the transposition operationand the scrambling of the color information of each image.Then,the SHA-256 algorithm is combined with the pseudo random sequence generator composed of several chaotic system,and the pseudo random sequence generated by the pseudo-random number generator is used for the first round of encryption of the image.Then,the key is XOR processed with the output value of SHA-256,the new value obtained is combined with the pseudo random sequence generator again,and the image is encrypted for the second round using the generated pseudo random sequence.Finally,the three encrypted images are reconstructed into a complete encrypted color image.The multiple chaos system is used in the whole process,which ensures the randomness of the generated encryption sequence.At the same time,there are a large number of keys,which expands the key space.The simulation results and theoretical analysis show that the algorithm has a large key space,good encryption effect and good anti-violent attack ability,and the security of the encryption algorithm is very high.