Supermarket chain Budgens has begun trialling facial-recognition technology in one of its London stores in a bid to thwart attempts by the city’s teenagers to buy alcopops and smokes illegally.

The trial uses a face-recognition system developed by firms OmniPerception and Charton. The unnamed Budgens store now has a camera installed in each of its three checkout lanes. As shoppers approach the tills, their faces are snapped and beamed back to a control centre in Worcester.

The software then plots points on the customer’s face and compares the read-out against a database of customers already identified as being too young to buy certain products. If the software finds a match, the store’s cashier is alerted and told to refuse sales of booze and fags.

Conversely, the software also highlights anyone who’s already been verified as old enough for a puff and a swig.

Anyone who hasn’t visited the store before and could be under age will be asked for ID by checkout staff. The cashier can then permit or deny the sale. Either way, the buyer's picture is retained for future use.

Charlie Willetts, managing director of Charton, told the BBC that only 1500 images are stored on the system currently. But he said that other supermarkets and convenience stores are interested in the system, which could result in a giant database of customer pictures snapped at stores.

Earlier this week, Register Hardware reported how cigarette machines in Japan could soon be fitted with cameras and facial recognition software to help verify the smoker’s age before a pack is dispensed.

Six Budgens stores have also opted for fingerprint recognition – but to stop staff claiming false working hours. The fingerprint scanners mean staff can’t dishonestly clock-in other members of staff who aren’t at work. Well, not without resorting to really desperate measures.

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