3D DWT-DCT based multiple watermarks for medical volume data robust to geometrical attacks

It is desirable to embed multiple diagnosis results into one medical volume data. Existing methods are lack of robustness. Robust multiple watermarks of medical volume data using 3D DWT-DCT is proposed to deal with this problem. The part of sign sequence of 3D DWT-DCT coefficients are used as feature vector, which is utilized to enhance the robustness against rotation, scaling, translation attacks. We describe how to obtain the feature vector of medical volume data and embed and extract the multiple watermarks. Simulation results demonstrate the proposed algorithm´s robustness.