Interpreting line drawings based on constraints between edges and vertices

Extracting 3D information of an object from its 2D projection is a primary objective in contemporary computer vision research and thus has long been studied. In this paper, a new method for reconstructing the 3D framework models of a planar object from its 2D hidden-part-drawn line drawing is proposed. The hidden-part-drawn line drawings are depicted under the perspective projection. Some constraints between edges and vertices are given on basis of the positional relations of lines and junctions in the drawing. We have established a linear system based on these constraints. The 3D framework information of a planar object can be obtained by solving the linear system. The feasibility of our method is proved by mathematics and the experiment results.