Presentation on theme: "Spatio-Temporal Relationship Match: Video Structure Comparison for Recognition of Complex Human Activities M. S. Ryoo and J. K. Aggarwal ICCV2009."— Presentation transcript:
Spatio-Temporal Relationship Match: Video Structure Comparison for Recognition of Complex Human Activities M. S. Ryoo and J. K. Aggarwal ICCV2009
Introduction Human activity recognition, an automated detection of ongoing activities from video is an important problem. This technology can use on surveillance systems, robots, human-computer interface. When using on serveillance systems,automaically detect violent activities is very important.
Introduction Spatial-temporal feature-based approaches have been proposed by many researchers. The method above have benn successful on short video containing simple action such as walking and waving. In real-world applications, actions and activities are seldom like this.
Related works Methods focused on tracking persons and bodies are developed [4,11],but their results rely on background subtraction. Approaches that analyze a 3-S XYT volume gained particular in past few years[3,5,6,9,13,16], they extracted relationship on features and trained a model.
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Related works In this paper, we propose a new spatial- temporal feature-based methodology. Kernel functions are built on relationship between features. After training features, match function uses for matching test data.
Hierarchical recognition We can combine low-level action into high- level action. For instance, hand-shake includes two sub- action, arm streching and arm withdrawing. Detecting hand-shake may like : st1 before wd1,st2 before wd2, st1 equals st2,wd1 equals wd2.
Experiments The dataset is UT-interaction dataset. The actions are performed by actors, each video contains shake hands,point,hug,push,kick and punch.