关键词: 在线轨迹压缩, 同步欧式距离, 偏移量计算, 评估误差

Abstract: In view of the fact that the existing online Global Positioning System（GPS） trajectory data compression algorithm based on the offset calculation cannot effectively be applied to the key point insufficient evaluation, this paper proposes a new online trajectory data compression algorithm based on the offset calculation named Key-Predecessor Fix Algorithm（KPFA）. This algorithm calculates the Synchronization Euclidean Distance（SED）and the accumulated offset to find out the key points with large amount of information. At the same time, it sets the threshold to correct the trajectory points between the current key point and the last key point to keep the trajectory information more completely. The experimental results show that compared with the Opening Window Time Ratio（OPW-TR）and Spatial Quality Simplification Heuristic Efficient（SQUISH-E） algorithms the average SED error of KPFA is the smallest and the running time is the fastest maintenance in 100, 000 ms when the compression ratio is the same. The KPFA has higher accuracy on the amount of information of the trajectory point evaluation and the running time is more stable.

Key words: online trajectory compression, synchronous Euclidean distance, offset calculation, evaluation error