A Complete Label Set for 3D-sketch Labeling

Semantics representation of 3D-sketch is fundamental to 3D-sketch understanding. Line labeling was a convenient approach to spatial semantics representation for 3D-sketches. However, all the existing label sets could not be used to label freehand 3D-sketches directly as these label sets were derived from perfect projections of 3D objects. These label sets had not been proved to be complete yet. In this paper, we propose a label set, named the 3DS label set, for 3D-sketches of the blocks world objects, which can be used to label the 3D-sketches directly without tidying. We firmly prove that the 3DS label set is complete for the 3D-sketches spatial semantics.