Secure Virtual World Access Based on Biometric Watermarking of 3D Avatar Face Mesh

Owing to the absence of a reliable access control tool in the virtual worlds, these spaces are more and more exposed to cybercrimes. In the guise of fictive identities, cybercriminals involve multiple avatars to perform illegal activities. To deal with this, setting up an access control mechanism in these digital environments is becoming necessary. In this paper, we propose an original access control solution based on an identity authentication approach that can assure the security of virtual spaces. Thus, only authentic users and respective avatars are allowed to accede into the virtual worlds and exploit their resources. The access control is based on the biometrics technique. The identity of virtual-world users’ is authenticated through their provided fingerprint while requesting the access. These fingerprints are later coded to generate biometric signatures serving as watermarks. In order to join the individual to their respective avatar, these signatures are inserted into the avatars’ face through a watermarking algorithm. The watermarking process is applied to the 3D avatar facial meshes. The embedded watermark is extracted when necessary to authenticate the avatars. The avatar identity is confirmed as authentic on the basis of an acceptance threshold of correlation values computed between the original watermark and the extracted one. The experimental investigations show that the proposed watermarking algorithm can keep a good imperceptibility and is robust facing up most of the attacks that could appear in a virtual environment. The registered authorized-user, FRR and EER rates at different attacks prove that the suggested approach is also efficient to distinguish genuine identities from impostor ones.