  Due to the recent demand of 3-D models in several applications like medical
imaging, video games, among others, the necessity of implementing 3-D mesh
watermarking schemes aiming to protect copyright has increased considerably.
The majority of robust 3-D watermarking techniques have essentially focused on
the robustness against attacks while the imperceptibility of these techniques
is still a real issue. In this context, a blind robust 3-D mesh watermarking
method based on mesh saliency and Quantization Index Modulation (QIM) for
Copyright protection is proposed. The watermark is embedded by quantifying the
vertex norms of the 3-D mesh using QIM scheme since it offers a good
robustness-capacity tradeoff. The choice of the vertices is adjusted by the
mesh saliency to achieve watermark robustness and to avoid visual distortions.
The experimental results show the high imperceptibility of the proposed scheme
while ensuring a good robustness against a wide range of attacks including
additive noise, similarity transformations, smoothing, quantization, etc.
