Event detection in video sequences: Challenges and perspectives

The growing need for information and high-quality video cameras has led to the proliferation of video based systems that perform tasks such as traffic monitoring, surveillance, etc. A basic component in these systems is the visual tracking of objects contained into a video sequence in order to estimate their paths. Generally, the framework of a video surveillance system includes the following steps: Environment modelling, object detection, classification and tracking of moving objects and description of their behaviours. Indeed, the main purpose of event detection systems is to characterize activities using unsupervised or supervised techniques. In the following paper, we present the state of the art of various event detection methods such as approaches used to extract primitives characterizing the movement then the means of classification.