Surface Reconstruction from Multiple Views of Painted Curves

AbstractA normal to the extremal contour of a 3D object is the same as the normal computed for the image contour projected on the unit sphere by the rays grazing the extremal contour. This fact is utilized in the present work to derive the parameters of quadric surfaces. We require three views of the point of intersection of two painted curves on an object. Out of the three views, one view must be chosen such that the image contours of the curves appear close to the extremal contours. Then the normals to the image contours (i.e., apparent contours) and the normals to the surface curves (i.e., contour generators) can be related through differential geometry to yield quadric representation of a surface at the point of interest