Medical Image Encryption Using Block-Based Scrambling and Discrete Wavelet Transform

Abstract

In today’s age of manifold advances in the field of medical imaging, a significant amount of sensitive and personal information related to patients is being transmitted electronically via images. With the advent of e-Health and Telemedicine in the vast field of medicine, there is a need to guarantee the authenticity and validity of the images being exchanged. The much-need security of medical images imposes the conditions of confidentiality, reliability and availability, and these can be attained by various Image Authentication methods and one such authentication is Image Encryption. The proposed work aims at an Image Encryption technique, which is a combination of Tiling, Scrambling and Image Transformation and Encryption of the image. The proposed architecture for encryption and decryption of a medical image is using a symmetric key, which gives the size of the tiles and the hash code of the image. The encryption algorithm divides the image into tiles of arbitrary size, scramble them using a scrambling technique and transform the scrambled image using Discrete Wavelet Transform (DWT). The hash code in the key is used to find out if tampering has taken place during transmission of the medical image.