A multi-medical image encryption algorithm based on ROI and DNA coding

Abstract With the rapid development of information technology in the field of electronic medicine, the confidentiality of medical images has received increasing attention. The research on the encryption of multiple medical images holds greater practical significance. In this paper, the encryption algorithm is designed specifically for the region of interest (ROI) in medical images. Different techniques and methods are used to encrypt ROI and region of non-interest (RONI) respectively. By combining improved Zigzag scrambling, DNA coding, and the Fisher-Yates shuffle, we place an emphasis on protecting the ROI, and achieve secure encryption for medical images of any number and size. In addition, a new one-dimensional chaotic system S-LCS with larger parameter space and better chaotic properties is proposed. In this encryption scheme, the information about the ROI serves as the secret key, and the initial values and parameters of the chaotic sequences required for encryption are calculated from this key. This strengthens the relationship between the key and the plaintext, enhancing the security of the key. Through testing and comparative analysis, it has been found that the encryption algorithm has high enough security, can resist various attacks, and has high encryption efficiency in the application scenario of multi-image encryption.