Secure medical image encryption scheme for Healthcare IoT using novel hyperchaotic map and DNA cubes

To enhance the security and transmission efficiency of medical data within the Healthcare Internet of Things (IoT), this study proposes a novel encryption scheme for medical images that integrates integer wavelet transform (IWT) with DNA encoding. The scheme aims to ensure the confidentiality of medical images while optimizing cloud storage and transmission speed. It employs pseudo-random sequences generated by a novel 3D hyperchaotic map. Initially, IWT is applied to extract the approximation components of the images, followed by a novel diffusion algorithm that masks critical information. A bit-level permutation mechanism further enhances encryption complexity by rearranging pixel positions. To augment security, the scheme introduces a random DNA operation, encoding the permuted images with a unique DNA technique and shuffling DNA bases using specialized DNA cubes. Performance analysis reveals that the decrypted medical images exhibit high visual fidelity, consistently achieving a $PSNR$ above 35 dB. Moreover, in terms of encryption efficiency, the proposed algorithm demonstrates faster processing speed, while its security performance is comparable to that of the current state-of-the-art algorithms.