Study On Transform-Domain-Based Quantum Image Compression-encryption Algorithm And Its Application

In the current digitized information society,the security and protection of image data are of great concern.With the explosive growth in the amount of the image data in recent years,the high dimensionality,the high resolution as well as the high redundancy of images have placed higher demands on the storage and the transmission.Traditional image encryption algorithms may cause delays in the encryption and decryption processes for the high computational complexity,particularly in application scenarios with high real-time requirements.With the rapid development of the quantum information technology,the realization of the encryption and secure transmission of image data by applying quantum technology has received extensive attention from researchers.Due to the parallel computing characteristics of quantum entanglement and non-localization,quantum computers provide a new solution for the secure transmission of image information.Therefore,quantum image encryption technology has great potential applications and research significance.To address the deficiencies of the current image encryption algorithms in multi-image real-time encryption,such as the high complexity,the restricted key space,and the vulnerability of linear operations to cryptanalysis methods such as exhaustive and differential attacks,transform-domain-based quantum image compression-encryption algorithms,the multi-image compression-encryption algorithm and its application in healthcare information management system are focused.The details of this thesis are as follows.To address the limitations of the existing pseudo-random number generator(PRNG)in sequence statistics,generation speed and security,as well as the demand for image encryption algorithms for simple and efficient PRNGs,the quantum particle swarm optimization(QPSO)algorithm is adopted to optimize the initial weights and thresholds of the backpropagation(BP)neural network and improve the convergence speed of the network.A new QPSO-BP-PRNG mechanism is constructed,and the chaotic sequences generated by the PRNG are utilized to perform pixel disruption and diffusion on the phase-truncated image in the Fr FT domain.An encryption algorithm for the single quantum grayscale image is investigated and an in-depth analysis of the defense against various common attacks is presented.The randomness test results show that the proposed QPSO-BP model provides high-quality pseudo-random sequences for the encryption system,and the simulation experimental results verify the high security of the quantum image encryption algorithm based on QPSO-BP-PRNG.For the current problems of the large image data redundancy and the limited transmission speed,the compression perception theory is introduced,and a quantum multi-image compression and encryption algorithm based on the quantum discrete cosine transform(QDCT)and 4-dimensional(4D)hyperchaotic Henon system is proposed.Since the sparse signals are concentrated into the high frequency domain by the QDCT,the amount of data to be transmitted is greatly reduced and the loss of the image information in lossy compression is effectively mitigated.To further improve the key sensitivity and algorithm security,the initial value of the 4D hyperchaotic Henon system is utilized as the key,and the applicability of the designed algorithm under different compression ratios is verified by simulation experiments.In addition,other transform-domain-based image compression and encryption algorithms are comparatively analyzed to demonstrate the advantages of the proposed algorithm in terms of security and efficiency.To address the conversion of the quantum representation model between the integer and real pixel-valued images in the current wavelet transform-based quantum image compression and encryption algorithms,i.e.,the quantum representation model for storing integer pixel-valued images is not applicable to storing compressed non-integer pixel-valued images.With the quantum representation of the real-valued digital signals(QRDS)for the non-integer pixel-valued images,the conversion of the inter-domain quantum line is thoroughly studied,and a quantum Haar wavelet transform(QHWT)-based quantum multiple color images compression and encryption algorithm is proposed.The quantum cyclic shift operation and the pixel backward diffusion strategy are constructed to realize the interactive influence between color and position information of multiple color images,which further improves the security of the designed algorithm and solves the problem that the compressed quantum images cannot participate in the subsequent encryption operation at present.The reliability,effectiveness,and strong resistance to common attacks of the proposed quantum multiple color images encryption algorithm are verified by a series of experiments.For the security risk in the transmission of electronic medical images,the traditional Mellin transform is extended to the quaternion transform domain in this thesis,the aperture is introduced as a part of the encryption system device.A nonlinear quadratic fractional Mellin transform(q Fr MT)with the chaotic aperture(CA)is constructed,and the nonlinear multi-image compression-encryption algorithm for telemedicine information management system is designed.Only users with the correct key are authorized to access sensitive medical data stored and transmitted as ciphertext in the system.The aperture device with the chaos-controlled arrangement of the sub-aperture not only increases the difficulty of illegally accessing or tampering with the privacy information of the patients,but also expands the key space of the system.The simulation results verify the security and feasibility of the telemedicine information management system by applying the proposed algorithm.The consumption of time and resources is reduced,and a possible solution is provided for secure transmission and storage of medical images.