Compatible Sliding-Windows Algorithm for Vessel Trajectory Compression

With the development of marine economy and data positioning technology, A large amount of vessel trajectory data has been generated. Data compression has become the key issue in the research of vessel trajectory big data. Since the compression rate of the existing vessel trajectory compression algorithms was not adjustable, we proposed a vessel trajectory compression algorithm with adjustable compression rate based on Sliding-Windows(SW) algorithm. The main idea was to adjust the compression rate by dynamically updating the vertical Euclidean distance threshold. The proposed algorithm could adapt to the dynamic change of channel capacity by dynamically adjusting the compression rate in online compression. The simulation results showed that compared with the traditional SW algorithm, the proposed algorithm not only realized the dynamic adjustment of compression rate, but also the compression error was less than that of the SW algorithm. Meanwhile the increase of computational complexity was almost negligible. This algorithm could also be used for online compression of other kinds of trajectory data.