Visual Crowd Surveillance Through A Hydrodynamics Lens

Video cameras monitoring the activity of people in public settings are commonplace in cities worldwide. At large events, where crowds of hundreds or thousands gather, such monitoring is important for safety and security purposes but is also extremely (technically) challenging. Human operators are generally employed for the task, but even the most vigilant humans miss important information that could ultimately contribute to unfavorable consequences. Major research efforts are under way to develop systems that cue security personnel to individuals or events of interest in crowded scenes. Essential are methods by which information can be extracted from video data in order to recognize crowd behaviors, track. © 2011 ACM