It's fair to be paranoid this weekend in San Francisco bars, taverns, and clubs -- somebody is watching you... and telling the world what the bar crowd is like on an app for iPhone or Android.



But that's not at all shady or sketchy, the CEO of SceneTap, a "nightlife startup" based in Texas that's behind the technology tracking the demographics of bar crowds, told SF Weekly.



It's being done in six other cities, too.

The face-recognition technology, which uses special cameras placed throughout bars to tell users what kind of crowd is on hand before they arrive at the bar, will be rolled out in 25 bars in San Francisco beginning Friday night. And it's not any more intrusive on your privacy than handing the bouncer your ID, according to CEO Cole Harper.



"We've been privacy advocates from day one," Harper told the newspaper. "SceneTap helps increase foot traffic by matching up people with the scene for them. So if you're with a group looking to grab a drink at a table and have an audible conversation, you can find a place ahead of time that isn't too crowded. On the other hand, if you're looking for a busier atmosphere, SceneTap can help you find that scene, too."



The service launched in July 2011 at 50 venues in Chicago and has "since expanded to Austin (TX), Bloomington (IN), Gainesville (FL), Athens (GA) and Madison (WI)," Harper said.



The data is not shared with the venues using the cameras or with police, Harper said. People whose faces are identified are not stored, either, he said.