Recognising Action as Clouds of Space-Time Interest Points

Much of recent action recognition research is based on space-time interest points extracted from video using a Bag of Words (BOW) representation. It mainly relies on the discriminative power of individual local space-time descriptors, whilst ignoring potentially valuable information about the global spatio-temporal distribution of interest points. In this paper, we propose a novel action recognition approach which differs significantly from previous interest points based approaches in that only the global spatiotemporal distribution of the interest points are exploited. This is achieved through extracting holistic features from clouds of interest points accumulated over multiple temporal scales followed by automatic feature selection. Our approach avoids the non-trivial problems of selecting the optimal space-time descriptor, clustering algorithm for constructing a codebook, and selecting codebook size faced by previous interest points based methods. Our model is able ...

• Type: Conference
• Year: 2009
• Where: CVPR
• Authors: Matteo Bregonzio (Queen Mary, University of London), Shaogang Gong (Queen Mary, University of London), Tao Xiang (Queen Mary, University of London)
• Keywords: Computer Vision, CVPR 2009, Recognising Action