A Blind Fragile Watermarking Method for 3D Models based on Geometric Properties of Triangles

In this paper, a blind fragile watermarking method is presented for 3D triangular mesh models. In the proposed algorithm, watermark data displace medians of the mark triangle instead of embedding them into the vertices, based on the method which is explained. The displacement leads to a new triangle. The proposed method embeds data into the middle of three sides of mark triangle in spherical coordinates. It is performed by fixing one component of the center of neighboring vertices to mark triangle by small and controlled changes. It also increases the number of mark triangles in their selection process and thereby it increases the embedding capacity. The proposed method is invariant to affine transformation including translation, rotation and uniform scaling, due to the use of the normalization process before the embedding and also detection stages. Simulation results show that the proposed method has higher embedding capacity compared to the similar algorithms with the capability of detecting destructive attacks.