CCNY-SRI @ TRECVid 2013 intED: a Human Interactive Event Detection System

In this paper, we present a interactive Event Detection (interactiveED) system evaluated in TRECVID 2013 competition. The proposed system is evaluated on all the seven event categories. Two channels of raw features: STIP-HOG/HOF and SURF/MHI-HOG – are extracted from down-sampled surveillance video frames. A Bag Of Words model is used to generate representations of segments of surveillance videos. Segments of videos are sampled using sliding windows. Spatial priors are utilized in two channels: Hot Region and Human Tracking Masks. Spatial priors are used for filtering noisy feature responses. Feature mapping technique is employed to generate more features, which potentially increase the separability of sample set in feature space. A cascade of SVMs are learned to tackle the classification task, with respect to different camera views. Human interaction is utilized as a post-processing layer to filter out false alarms. A Graphical User Interface (GUI) is developed to help an expert user to accomplish the task efficiently and conveniently.