Shape Recovery for Input of a Rough 3D Shape by its 2D sketch$

A sketch is often used as a simple and useful medium to communicate a rough 3D shape among humans. In order to realize man-machine communication of rough 3D shape using a sketch, we have to discuss the problem how to recover the 3D shape implied by a human using a 2D sketch. In this paper, we propose to recover the 3D shape from its sketch interactively based on some qualitative features that would be important to characterize 3D shapes implied with sketches. We also propose to infer the 3D shape that is not drawn in the sketch from the shape recovered from the drawn part.