Quantitative similarity calculation method for trajectory-directed line using sketch retrieval

Abstract

Moving objects may have various kinds of topological events when they move relative to a directed line, such as moving in/out, folding back and stopping. This research develops a trajectory-directed line query mode using sketch-based retrieval in order to realize the query of topological relationship between a trajectory and a directed line. The research also proposes a quantitative similarity calculation method for trajectory-directed line. The sketched stroke-directed line is used as input query condition and is described as a sequence of key points for semantic association. The trajectory-directed line to be queried is also described as a sequence of key points. The time sequence distance metric is used to calculate the similarity between them. For the trajectory-directed line with different number of key points, the similarity calculation is carried out using two kinds of distance matching methods. The results show that the method is simple and feasible, and can realize the quantitative query of trajectory data.