Medical image encryption using edge maps.

This paper presents a medical image encryption algorithm using edge maps derived from a source image. The algorithm is composed by three parts: bit-plane decomposition, generator of random sequence, and permutation. It offers users the following flexibilities: (1) any type of images can be used as the source image; (2) different edge maps can be generated by various edge detectors and thresholds; (3) selection of appropriate bit-plane decomposition method is flexible; (4) many permutation methods can be cascaded with the proposed algorithm. A significantly large key space and strong key sensitive are possessed by the proposed algorithm to protect different types of medical images. Furthermore, it has a wider applicability than other methods for fuzzy edge maps. Experiments and security analysis further demonstrate that it has a strong resistance against various security attacks and outperforms other state-of-the-art methods. HighlightsA lossless edge maps based image cryptosystem for medical image is proposed.Many kinds of edge maps with various edge detectors can be applied as the keys.The algorithm costs little time with a machine-friendly binary system.The scheme shows a higher security level with other state-of-the-art methods.