Crypto-watermarking scheme for tamper detection of medical images

摘要

Medical images of patients are often exchanged among specialist physicians, radiologists, hospital authorities and patients for remote monitoring and assessment as part of telemedicine. With the revolutions in the technology, the threat models and attackers are evolving on a daily basis and hence there is a constant need for the development of novel schemes that can protect personal information. In this paper, a non-blind fragile watermarking is developed to invisibly hide and integrate patient's unique information such as biometrics in their radiological images for secure authentication, integrity verification and tamper detection purposes. The concept of compressive sensing theory is employed with discrete cosine transform to improve confidentiality. The performance of the proposed scheme is tested and evaluated on three types of medical images: X-ray, computed tomography and magnetic resonance imaging. The proposed scheme presents a means of verifying data integrity when medical images are subjected to attacks. The experimental results showed that the scheme invisibly hides high payloads of patient's unique identities, apart from providing better tamper detection. The simulation results show that the proposed scheme provides high imperceptibility up to 92 dB and high payload capacity of up to 1 bpp.