The parallel and precision adaptive method of marine lane extraction based on quadtree

Abstract

Extracting the marine lane results from the ocean spatial big data is a challenging problem. One of the challenges is that the quality of the trajectory data is quite low, and the trajectory data quality is extremely different in different areas. A parallel and precision adaptive method of marine lane extraction based on QuadTree is proposed to meet this challenge. The method takes advantage of several methods including average sampling, interpolation, removing noise, trajectory segmentation, and trajectory clustering based on GeoHash encoding through the MapReduce parallel computing framework. The preprocessing phase can effectively simplify the big data and improve the efficient of data processing. Based on the QuadTree data structure, a parallel merge filtering algorithm is proposed and implemented used Spark framework. The algorithm performs grid merging on the sparse grid regions, and obtaining a new grid result with different size. The sliding local window filtering algorithm based on the QuadTree is proposed to obtain the marine lane grid set data. Applying the Delaunay triangulation method on the grid data, the multi-precision marine lane results are effectively extracted. The experimental results show that the proposed method can automatically extract multi-precision marine lane using the trajectory data near the coast with high and low grid precision.