| The rapid progress in the field of information technology has brought a certain impact on all aspects of our lives.The medical field is also making use of the advanced technology in the field of computer network to move towards informatization.Especially since the outbreak of the epidemic,remote diagnosis,remote consultation and other services have become popular.In order to facilitate doctors to accurately grasp the patient’s condition,a lot of medical images are stored and transmitted on the network.However,in this process,due to the openness of the network,a large number of users can access the Internet,which makes the medical images in the network face the problem of being attacked or tampered,which poses a threat to the privacy security of patients,and even brings hidden dangers to clinical diagnosis.Therefore,how to strengthen the security protection of medical images on the network and the privacy protection of patients has been a hot topic.At present,due to its robustness and other characteristics,digital watermarking technology is widely used to deal with medical image privacy protection issues.However,medical images are sensitive and require high integrity of information.Therefore,the common digital watermarking technology in the medical field is zero watermarking technology.Based on Local Binary Patterns(LBP),a zero watermark algorithm for two-dimensional medical images and three-dimensional medical volume data is put forward.The main research work in this paper is as follows:(1)A robust zero-watermark algorithm for medical images based on LBP-DCT is studied.Firstly,LBP and Discrete Cosine Transform(DCT)are introduced,utilizing the strong feature extraction ability of LBP and the robustness of DCT to extract features from medical images.The low frequency feature coefficients are obtained.Then,the feature vectors of medical images are obtained by perceiving hash functions.Next,encrypting watermark images using logistic chaotic maps,and then embedding the encrypted watermark into the medical image by using zero-watermark technology.Through the analysis of experimental results and the comparison of algorithms,it can be found that the algorithm has strong anti-attack ability and good robustness.(2)Based on two-dimensional medical image watermarking,a medical volume data watermarking algorithm based on LBP-DCT is studied.Firstly,taking the medical volume data as the research object,extracting the low frequency characteristic coefficients of medical volume data by combining LBP and DCT,and then using perceptual hash to get the feature vectors of medical volume data.With the better protection of visual effect and image quality by zero watermark technology,the encrypted watermark is embedded into medical volume data,and the process is reversible.From the experimental results,we can see that the algorithm maintains good robustness in the face of common traditional attacks and some geometric attacks. |
