Towards robust and flexible blind watermarking system for copyright protection of 3D models

Recently, much interest is being taken to protect the copyright of digital data and prevent illegal duplication of it. Towards this purpose, this paper presents a robust and flexible blind watermarking system suitable for proving ownership claims for 3D models. The basic idea is to decompose the original model into a series of details at different scales by using particular basis functions derived from wavelet transform; the watermark is then inserted in different resolution levels by modifying the norms of basis coefficients. The robustness of the presented system is achieved by embedding the watermark in a normalized and resampled version of the host mesh, which are quite insensible to geometrical attacks. While, the flexibility is obtained by increasing embedding strength on low frequency components, in which alterations are less visible for human eyes. Experimental results show the validity of the proposed system both in terms of imperceptibility and robustness against a wide class of attacks.