Research On Quantum Image Encryption Based On Quantum Circuit Model

With the popularity of computer applications and the rapid development of multimedia information technology,information storage technology and network technology,the image has become one of the main methods of obtaining many kinds of effective information.The image may involve military secrets,business secrets or individual privacy information;it has becoming a common concern problem to protect image security and prevent information leakage.The protection methods of the classic image security mainly consist of the image encryption technology and image authentication technology,although these two ways can meet the encryption requirements of the image to a certain degree,but in today's big data era,how to encrypt images effectively and fast is always a problem that we must focus on.Quantum computing has the characteristics of parallel computing,making it an important research direction for high-performance computing.With the development of quantum computing,the processing of images has extended to the quantum field.Quantum image encryption has become a research hotspot area under the background of the rapid development of quantum computing.The research on quantum image encryption is becoming one of the hot spots of research since 2013.Unlike quantum secure communication,quantum image encryption is a technology that protects the information of quantum images stored in qubits based on a quantum computing models.This paper mainly improves the security problems(such as the periodicity of image scrambling)of quantum image encryption algorithms based on image scrambling technology.Then we proposed a series of evaluation indexes for evaluating quantum image encryption algorithm,the main results of the research include the following three aspects:(1)We proposed a quantum image scrambling encryption algorithm based on image partition.Based on image partition,firstly,dividing the original image into several subgraphs of the same size according to the position coordinates,performing different quantum image scramble operations on each subgraph,and then operating double random phase encoding(DRPE)on the scrambled image to obtain the cipher image.This method can break the periodicity of image scramble operation to a certain degree.When the attacker makes an exhaustive attack,he/she cannot deduce the original image information even he/she gets some information of the original image through iteration,and realizing the effective encryption.(2)We proposed a quantum image encryption algorithm based on iterative framework of frequency-spatial domain transforms.This algorithm achieves the purpose of breaking the periodicity of spatial scrambling technology by performing the quantum location transformation on the pixel location information of the original quantum image in the spatial domain and performing the quantum transformation operation sequentially and iteratively on the color information in frequency domain.The key of this algorithm includes the iterative parameter of Fibonacci transform,the iterative parameter of geometric transformation,the geometric transform matrix and binary sequence of double random phase encoding technology,theoretically,it has an infinite key space,which is enough to resist brute-force attacks.Using this quantum image encryption iterative framework,different quantum image encryption algorithms can be designed when we combine different quantum transformations and iteration parameters.(3)Aiming at the evaluation of quantum image encryption algorithm,the evaluation indexes are given after simulation experiments and analysis,which includes performance analysis and security analysis.Performance analysis is the analysis of network complexity of quantum circuits(which is expressed by the number of gates in quantum computing).While security analysis includes key analysis(including the size of key space and key sensitivity analysis),statistical analysis(including the correlation of adjacent pixel,histogram analysis,information entropy and distribution density of scatter plot).The distribution density of scatter plot is a new analysis index proposed in this paper for better statistical analysis.It can reflect the pixel distribution of cipher images and use to compare the encryption effects of different quantum image encryption algorithms.The research work mentioned above can improve the security of quantum image encryption algorithm based on image scrambling technology and provide reference for the design of quantum image encryption algorithm using image transformation operation.In addition,the evaluation indexes of quantum image encryption algorithms summed up and proposed in this paper can satisfy the requirements of the quantum image encryption algorithm evaluation.