Learning Activities from Video

Muralikrishna Sridhar , Anthony Cohn and David Hogg

In this project we have devoloped a method for learning about human activities from video. The idea is to look for repeating patterns of changing spatial relationships between tracked entities in the scene. Having discovered these patterns or events in this way, we look at the roles objects play in these events and thereby produce a taxonomy of objects.

Sun

Data Sets and Results

We demonstrate our framework on a kitchen set up, where the scene consists of hands simulating the preparation of various dishes, lasting around 10 minutes. We obtain a event taxonomy and a object taxonomy as shown.

Data Set Sample Download Video Sun

Publications

  1. Muralikrishna Sridhar, Anthony Cohn, Hogg David C, Learning Functional Object-Categories from a Relational Spatio-Temporal Representation ,ECAI 08. Download Sun

Method

  1. Activities are represented in a activity graph that captures spatio-temporal interactions between objects.

  2. Events are learned by mining frequent subgraphs from the activity graph. An Event taxonomy capturing "part of" relationships is induced by relating events.

  3. An object taxonomy is learned by hierarchical clustering of objects, which are represented in terms of the role they play in the learned events.

Sun