At some point in the future, Facebook  could be a far bigger threat to our privacy  than we previously assumed. That’s because the social network is building the world’s biggest database of faces that theoretically can be used for biometric recognition.
Martin Kaste of National Public Radio actually called it a super database  of labeled faces that may contain a billion faces someday.
The danger to privacy is that the government could request the pictures from Facebook, says Amie Stepanovich, director of the domestic surveillance project at the Electronic Privacy Information Center.
The photo database, she told NPR, is the largest in the world and has “been formed by people voluntarily submitting pictures to Facebook and identifying who they belong to.”
“As we’re seeing specifically over the past few months, no matter how much a company attempts to protect your privacy, if they’re collecting information about you, that information is vulnerable to government search,” Stepanovich said
How your picture could be used
Matching an individual’s Facebook picture is possible with today’s facial recognition software, Neeraj Kumar , a professor of computer science and engineering at the University of Washington, told NPR — although Kumar did say it only currently works with a high quality picture. Having multiple pictures of a person is essential, he said.
“If you had lots of photos of each person … you could build a model for Martin, a model for me, a model for other people. Now you have a custom-tuned model for each person,” Kumar said.
It likely isn’t possible to match faces using footage from surveillance cameras, as is often done on television dramas. That’s because the pictures from such cameras simply are not high quality enough to work with most facial recognition programs, said Manuel Cueva, a facial recognition expert with the Los Angeles County Sheriff’s department.
“If the image is such poor quality, you may not get any results period,” Cueva said.
However, a British company called NEC IT Solutions claims it has a facial recognition  program that can identify people on that level. Currently the software is being sold to stores to recognize important customers, NPR reported.
The facial recognition software police often use is now about 95 percent accurate, Kumar said.
Facebook already can recognize your face
Facebook does seem to have the capability to recognize faces from pictures posted on it. The social network’s “Tag Suggest ” feature uses facial recognition technology to speed up labeling or tagging friends, NBC News reported.
“Our goal is to facilitate tagging so that people know when there are photos of them on our service,” Erin Egan, Facebook’s chief privacy officer, told NBC News. Facebook’s software is capable of recognizing faces and sorting through them.
Facebook bought Face.com, an Israeli company that specialized in developing facial recognition software, for $60 million last year . One of Face.com’s founders, Yaniv Taigman, coauthored a paper called Leveraging Billions of Faces to Overcome Performance Barriers in Unconstrained Facial Recognition in 2011.
Some of Face.com’s employees are now reportedly working at Facebook’s headquarters in Silicon Valley. It isn’t clear what they are doing there but it seems as if Facebook  is trying to perfect the capability for unconstrained facial recognition.