Earticle

Formal model of spatial directional relation is one of the most important parts in the area of spatial relation, and it is necessary to develop a new model with high generality and practicality. Firstly this paper analyzes the characteristics and disadvantages of the present models. Secondly it introduces in detail the basic notion and construction method of quadtree histogram。Thirdly a new approach to judging basic and special spatial directional relations based on quadtree histogram is proposed. Finally in order to prove the correctness of this model, several examples are given. The experimental results show that this model is feasible.