A SRG-based online composite graphic recognition strategy for sketch-based user interface

A spatial relation graph (SRG) and its partial matching method are proposed for online composite graphics representation and recognition. A conditional partial permutation strategy is also proposed to reduce the computational cost of matching two SRGs, which is originally an NP-complete problem as graph isomorphism is. Experiments show that the proposed SRG-based approach is both efficient and effective for online composite graphics recognition in sketch-based graphics input systems.