Implementation of a Reversible Watermarking Technique for Medical Images

Abstract

Electronic health records (EHR) contain patients' medical as well as personal details. With the increased use of digital media, these data are stored and transferred through the electronic media all over the world. This makes it vulnerable to unauthorized people. Digital image watermarking can be a useful process of protecting these data from attacker but causes severe and unrecoverable damage to cover media. In the case of highly sensitive images like medical images, this might creates a problem during further diagnosis. In this chapter, a reversible data hiding algorithm is proposed which also is capable of holding a large chunk of data without affecting the cover media. The main cover image is first reconstructed and hidden behind a bigger media and then the extra pixels are used to hide encrypted forms of EHR data along with an authentication signature. As EHR data and the digital signature is passed through various encryption stages while encoding, it is made more secure. The algorithm is developed on the spatial domain adding some cautious measures which made it fragile as well.