前景物件軌跡提供豐富及連續的動態資訊，可提供監視影片之事件分析使用，這些軌跡可經由一張一張畫面中追蹤前景物件來取得。然而，當前景物件出現重疊情況時，因為物件遭到遮蔽，因而造成錯誤的軌跡追蹤結果。在此篇論文中，我們提出一種利用軌跡串接來即時進行後處理的方式解決物件重疊的問題。分析前景物件串接，我們的方法可在物件數量發生變化的前後畫面中，找出重疊或分離物件之間的關係，並利用分離的個別前景物件在重疊前景物件中切割出相對應的個別前景物件，因此可以取得每一個重疊情況中的前景物件的正確個別軌跡。如實驗結果所示，相較於之前的方法，我們的方法可達到更佳的追蹤結果。

Trajectories of foreground objects provide rich and continuous motion information for event analysis in surveillance videos. These trajectories can be obtained by tracking foreground objects frame by frame. However, when occlusions between foreground objects occur, the tracking results will be incorrect. In this paper, we propose a real-time post processing method to solve the occlusion problem using trajectory links. By analyzing trajectory links, our method can identify the respective occlusion relationships between objects in the frames where the number of objects changes. Then, the individual foreground object separated from the overlapped foreground objects. Therefore, our method can retrieve individual trajectories of occluded foreground objects. As shown in the experiments, our method can achieve better performance than previous tracking methods.

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