Design of a Robust Watermarking Algorithm against the Geometric Distortion for Medical Image Security

This study suggests using a selected geometric invariant point through the whole processing procedure of an image and inserting and extracting based on the invariant point so that it will be robust in a geometric transformation attack. The introduced algorithm here is based on a watershed splittling method in order to make medical images strong against RST transformation and other processing. It also helps to maintain the watermark in images that are compressed and stored for a period of time.