Reversible watermarking in medical imaging with zero distortion in ROI

Securing images by watermarking is practically unused in medical practice despite its undeniable advantages. This paper proposes a method that tries to solve this problem. It is able to secure medical images by watermarking without any changes in those areas of images that carry medical information. It thus allows direct diagnosis of images in the watermarked state. The proposed method combines three fundamental approaches that offer suitable methods for watermarking medical images: Zero, Reversible and RONI watermarking. The proposed method has been deployed on a large database (60,000 images) and the very promising results of this experiment are described and discussed in detail in this article. The security of the proposed method from different perspectives is also discussed. Resistance to attack by cropping-out part of the image, resistance to steganalysis and security after unveiling the method or algorithm used. The aim was to propose such a method of medical images watermarking, which eliminates the disadvantages of existing methods and will be applicable in everyday hospital practice.