Advanced Surveillance: From Tracking To Event Detection

Abstract

The authors suggest an automatic surveillance system based on a robust and simple algorithm for foreground detection and tracking of multiple objects in complex environments. It is possible to obtain enough information from the characteristics of the detected objects, their centroid's position and their trajectories as to detect some predefined events. Working without the operator supervision the application analyses the video streams from the CCTV surveillance system, discarding empty scenes for monitoring or recording, showing to the operator those fulfilling predefined requirements, like crowding, and rising an alarm to call the operator attention when it decides that an event may be taking place. The application is based on very simple algorithms in order to allow a single computer the analysis of up to eight video streams in real-time. Blob and scene characteristics are used to create a low-level description of predefined events. The application detects events by comparing the sequence's parameters with those associated with the events for the current scenario. The provided examples are tailored to the specific demands of a surveillance system in a public transport environment.