. Figure 1: The bottom row shows the virtual face animated by retargeting expressions from the source face (top row). AbstractWe present a method for transferring facial animation in real-time. The source animation may be an existing 3D animation or 2D data providing by a video tracker or a motion capture system. Based on two sets of feature points manually selected on the source and target faces (the only manual work required), a RBF network is trained and provides a geometric transformation between the two faces. At each frame, the RBF transformation is applied on the new feature points positions of the source face, resulting in new positions for target feature points according with the expression of the source face and the morphology of the target face. According to their displacements along time, we deform the target mesh on the GPU with the linear blend skinning (LBS) method. In order to make our approach attractive to novice user, we propose a procedural technique to automatically rig the target face by generating vertices weights for the skinning deformation. To summarize, our method provides interactive expression transfer with a minimal human intervention during setup and accepts various kind of animation sources.

Facial animation details like wrinkles or bulges are very useful for the analysis and the interpretation of facial emotions and expressions. However, outfitting a virtual face with expression details for real-time applications is a difficult task. In this paper, we propose a mono-camera acquisition technique of facial animation details and a technique which add a wrinkle map layer (fine-scale animation) to a skinning layer (large-scale animation) for real-time rendering of a virtual 3D face. The acquisition is based on ratio image computed from two pictures of a same face, with and without expression. The real-time dynamic wrinkles technique is based on a small set of reference poses. These two methods offer an easy and lowcost way to capture facial animation details and use it for real-time facial animation.

This paper presents a method to add fine details, such as wrinkles and bulges, on a virtual face animated by common skinning techniques. Our system is based on a small set of reference poses (combinations of skeleton poses and wrinkle maps). At runtime, the current pose is compared with the reference skeleton poses, wrinkle maps are blended and applied where similarities exist. The poses evaluation is done with skeleton's bones transformations. Skinning weights are used to associate rendered fragments and reference poses. This technique was designed to be easily inserted into a conventional real-time pipeline based on skinning animation and bump mapping rendering.

International audiencePreparing a facial mesh to be animated requires a laborious manualrigging process. The rig specifies how the input animation datadeforms the surface and allows artists to manipulate a character.We present a method that automatically rigs a facial mesh based onRadial Basis Functions and linear blend skinning approach.Our approach transfers the skinning parameters (feature points andtheir envelopes, ie. point-vertex weights),of a reference facial mesh (source) - already rigged - tothe chosen facial mesh (target) by computing an automaticregistration between the two meshes.There is no need to manually mark the correspondence between thesource and target mesh.As a result, inexperienced artists can automatically rig facial meshes and startright away animating their 3D characters, driven for instanceby motion capture data