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Efficient Depth Restoration from 2D Line Drawings with Line Segments and Curves

A 2D line drawing is a direct way to illustrate a 3D object. 3D reconstruction from a 2D single line drawing is an important research topic in the area of computer vision and geometric modeling. In this paper, we present an approach to reconstruct objects from single 2D line drawings with line segments, arcs and B-splines. Firstly, planar and curved faces are identified in the line drawing. Then, with a depth estimation algorithm to establish the initial depth of the vertices, the wireframe is reconstructed by hierarchical optimization-based method. Finally, planar and curved faces are reconstructed. The experimental results show that the recovered objects correspond to the human perception. The time complexity shows that our approach is in high-efficiency.