NURBS Warps
نویسندگان
چکیده
Standard Free-Form Deformations (FFD) built upon tensor-product B-Splines have been proved useful to model the warp between two views of a deformable surface. In this paper, we show that the standard FFD is the affine projection of a threedimensional tensor-product B-Spline surface. We construct a new tensor-product warp relying on Non-Uniform Cubic B-Spline: the NURBS-Warp. We show that this new warp is an extension of the standard FFD that describes the perspective camera model. We propose algorithms that compute the parameters of a NURBS-Warp from point correspondences. Our NURBS-Warp is compared to the standard FFD warp for both synthetic and real images. These experiments show that our NURBS-Warp gives better results than the other warps, especially when the perspective effects are important.
منابع مشابه
Fonctions de déformation image produit tensoriel généralisées Generalized Tensor-Product Warps
The inter-image flow field is often modeled by some parametric warp function. Nearly all warps in the literature are based on a linear combination of control points, as for example the Free-Form Deformation (FFD) warp which uses the tensor-product of B-splines. It has been recently shown that the FFD warp models the affine projection of a deforming surface. This is also the case for all tensorp...
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