Robust zero-watermarking for medical image based on DCT

When designing watermarking algorithm of the medical image, one of the principal problems faced is how to determine the region of interest (ROI). This paper proposes a zero-watermarking algorithm of the medical image using DCT, which can effectively solve this problem. This algorithm can enhance medical image security, confidentiality and integrity in the application for the clinical. The algorithm combines the visual feature vector of images, encryption technology with the third party authentication, and avoids the selection of ROI to speed up watermarking embedding and extracting. The simulation results demonstrate the algorithm has desired robustness against common attacks and geometric attacks, such as JEPG, rotation, scaling and translation, etc.