Improvements relating to event detection

摘要

A method of event detection for detecting the occurrence of an event in a crowd is disclosed. The method includes the steps of providing video footage of the crowd, which video footage includes a series of image frames; calculating a series of values representative of the crowd dynamics, which series of values is calculated in dependence on the series of image frames; analyzing the series of values to identify any discrepancies occurring in the series of values; and, in response to identifying a discrepancy, providing an output signal to alert an operator that an event has been detected. In preferred embodiments, the series of values are related to the complexity of the crowd dynamics. Apparatus suitable for carrying out such a method is also disclosed.

主权项

1. A method of detecting the occurrence of an event in a crowd based on analysis of video footage of the crowd, the video footage comprising a series of image frames, the method being performed by at least one processor and comprising the steps of:
(a) receiving the video footage at the at least one processor; (b) calculating, for each of the series of image frames, a complexity value indicative of overall crowd movement dynamics, the complexity value being calculated in dependence on said each of the series of image frames, thereby calculating a series of complexity values; (c) analysing the series of complexity values to identify any changes occurring among the series of values; and (d) in response to identifying a change among the series of complexity values having a magnitude in excess of a threshold, transmitting an output signal to alert an operator that the event has been detected.