EPFL’s Computer Vision Laboratory (CVLab), now has a new tool that makes it possible to follow multiple players at once on a field or court, even when they’re buried under a pile of bodies in a rugby match or crouched behind another player. The athletes are represented on a screen with a superimposed image bearing their jersey color and number, so spectators, referees, and coaches can easily follow individuals without mixing them up. And there’s no need for the players to wear extra gear or RFID chips. The system is made up of eight standard cameras - two on each side of the field or court, two that film from above and two that zoom – and three algorithms. After a tackle, goal, basket, or pileup, the system re-attributes the jersey number to each player automatically. No more getting lost in the crowd.
Three algorithms make the system work. The first detects individuals at a specific moment in time, independently of where they were the moment before or after. To do this, it slices the playing area into small 25 cm2 squares, removes the background in all the images simultaneously, and from this deduces the probability of the presence of a player in each of the small squares. The other two algorithms connect the results obtained for each moment in order to establish individual trajectories. All three use global optimization methods, resulting in a very robust system capable of tracking people in real time in a reliable manner. Researchers work with other applications, like tracking pedestrians to monitor traffic in an area, or following the movement of clients in a store for marketing purposes.
More information:
http://actu.epfl.ch/news/new-technology-tracks-multiple-athletes-at-once/
More information:
http://actu.epfl.ch/news/new-technology-tracks-multiple-athletes-at-once/