NEW YORK, USA (AP) — Eyeing that can of soda in the supermarket cooler? Or maybe you’re craving a pint of ice cream? A camera could be watching you.

But it’s not there to see if you’re stealing. These cameras want to get to know you and what you’re buying.

It’s a new technology being trotted out to retailers, where cameras try to guess your age, gender or mood as you walk by. The intent is to use the information to show you targeted real-time ads on in-store video screens.

Companies are pitching retailers to bring the technology into their physical stores as a way to better compete with online rivals like Amazon that are already armed with troves of information on their customers and their buying habits.

With store cameras, you may not even realise you are being watched unless you happen to notice the penny-sized lenses. And that has raised concerns over privacy.

“The creepy factor here is definitely a 10 out of 10,” said Pam Dixon, the executive director of the World Privacy Forum, a non-profit agency that researches privacy issues.

At the National Retail Federation trade show in New York earlier this year, a smart shelf on display by Mood Media tried to detect “happiness” or “fear” as people stood in front it — information a store could use to gauge reaction to a product on the shelf or an ad on a screen. Cineplex Digital Media showed off video screens that can be placed in malls or bus stops and try to tell if someone is wearing glasses or sporting a beard, which in turn can be used to sell ads for new frames or razors.

The screens can also be placed at the drive-thru. A minivan pulling into a fast food restaurant, for example, might get an ad for a family-sized meal on the video screen menu.

For now, the cameras are in just a handful of stores.

Kroger, which has 2,800 supermarkets, is testing cameras embedded in a price sign above shelves in two stores in the suburbs outside Cincinnati and Seattle. Video screens attached to the shelves can play ads and show discounts. Kroger said the cameras guess a shopper’s age and sex but the information is anonymous and the data is not being stored. If the tests work out well, the company said it could expand it into other locations.

Walgreens, which has more than 8,000 drugstores, installed cooler doors with cameras and sensors at six locations in Chicago, New York, San Francisco and Bellevue, Washington. Instead of the usual clear glass doors that allow customers to see inside, there are video screens that display ads along with the cooler’s contents.

Above the door handle is a camera that can try to guess ages and track irises to see where you are looking, but Walgreens said those functions are off for now. The company said the cameras are currently being used to sense when someone is in front of the cooler and count the number of shoppers passing by. It declined to say if it will turn on the other functions of the camera.