Cascading quantum walks with Chebyshev map for designing a robust medical image encryption algorithm

The secure storage and transmission of healthcare data have become a critical concern due to their increasing use in the diagnosis and treatment of various diseases. Medical images contain confidential patient information, and unauthorized access to or modification of these images can have severe consequences. Chaotic maps are commonly used for constructing medical image cipher systems, but with the growth of quantum technology, these systems may become vulnerable. To address this issue, a new medical image cipher algorithm based on cascading quantum walk with Chebyshev map has been presented in this paper. The proposed system has been tested and found to have high levels of security and efficiency, with UACI, NPCR, Chi-square, and global information entropy values averaging at 33.48095%, 99.62984%, 248.92128, and 7.99923, respectively.