A dynamic hierarchical clustering method for trajectory-based unusual video event detection.

Jiang, Fan; Wu, Ying; Katsaggelos, Aggelos K · IEEE Trans Image Process · 2009

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Abstract

The proposed unusual video event detection method is based on unsupervised clustering of object trajectories, which are modeled by hidden Markov models (HMM). The novelty of the method includes a dynamic hierarchical process incorporated in the trajectory clustering algorithm to prevent model overfitting and a 2-depth greedy search strategy for efficient clustering.