Driving 3D morphable models using shading cues

摘要

In this paper we show how surface orientation information inferred using shape-from-shading can be used to aid the process of fitting a 3D morphable model to an image of a face. We consider the problem of model dominance and show how shading constraints can be used to refine morphable model shape estimates, offering the possibility of exceeding the maximum possible accuracy of the model. We use this observation to motivate an optimisation scheme based on surface normal error. This ensures the fullest possible use of the information conveyed by the shading in an image. Moreover, our framework allows estimation of per-vertex albedo and bump maps which are not constrained to lie within the span of the model. This means the recovered model is capable of describing shape and reflectance phenomena not present in the training set. We show reconstruction and synthesis results and demonstrate that the shape and albedo estimates can be used for illumination insensitive recognition using only a single gallery image.