Digital image security based on data hiding and cryptography

The implementation of a system that combines encryption standards with watermarking techniques to provide security to exchanged medical images is the main concern of this paper. The system is based on a hybrid algorithm that applies the techniques of encryption and watermarking to offer different security features to medical images transmitted between healthcare entities. Based on the proposed algorithm, the authenticity and integrity of the transmitted images can be verified either in the spatial domain or in the encrypted domain or in both domains. This is achieved by joining the watermarked image and its encrypted version after embedding two unique watermarks; one in the plain image and one in the encrypted image. The proposed algorithm makes use of the concept of bit planes where two images consists of 8-bit planes combined to form a single image having 16-bit planes. The algorithm provides high embedding capacity while keeping low computational complexity.