Card counting, a strategy made famous by the film Rain Man, involves remembering which cards have been played, and which might be likely to turn up. An abundance of low-value cards in the discard pile can tip the odds slightly in favour of the gambler, and a card counter bets big only then.
The strategy isn’t illegal, but casinos will move suspected card counters to a new table, where the counters are forced to start afresh, or simply ban them. Krists Zutis and Jesse Hoey at the University of Dundee, UK, have developed a system to help casinos spot card counters quickly.
A stereo camera mounted above the table records the action. A computer processes the video feed to identify cards as they are dealt, face up, and monitors their value. The camera also records the precise height of betting chip stacks and the computer uses the information to work out betting patterns.
By comparing the cards and gambling patterns, the computer can identify a card counter inside 20 hands – even if the gambler starts off with a run of high bets to confuse the system. The work will be presented at the International Conference on Computer Vision Systems in Liège, Belgium, this month. …