A new study looks at privacy in a world where computers can increasingly recognize faces in a crowd or online. Alessandro Acquisti at Carnegie Mellon University's Heinz College in Pittsburgh, Pennsylvania, led the study. Professor Acquisti says social networks like Facebook and LinkedIn represent some of the world's largest databases of identities. He sees increasing threats to privacy in facial recognition software and cloud computing -- the ability to store huge amounts of information in data centers. "The convergence of all these technologies -- face recognition, social networks, cloud computing -- and all these advances in ... data mining are creating this world where you can blend together online and offline data. You can start from an anonymous face and end up with sensitive inferences about that person." Recognition systems measure things like the size and position of a nose, the distance between the eyes and the shape of cheekbones. The software compares lots of images to try to identify the person. Facial recognition programs are used in police and security operations. But the software is increasingly popular in other uses, including social media sites.For the study, the Carnegie Mellon team used software from Pittsburg Pattern Recognition, or PittPat. Google bought that company last month. The software can recognize faces in photos and videos. The researchers did three experiments. First, they collected profile photos from a dating website. Its users try to protect their privacy by not listing their real name. But comparing their photos to pictures on Facebook identified one out of ten people.In the second experiment, the Carnegie Mellon researchers asked permission to take pictures of students on campus. They compared these to photos on Facebook. This time they correctly identified one-third of the students. In the third experiment, they tried to see how much they could learn about people just from a photo. They found not only names but birthdates, personal interests and even locations, when people listed them. And Professor Acquisti says "face recognizers" keep improving. In June, Facebook launched a facial recognition system to help users "tag" or list the names of people in photos. Germany became the first country to declare this software a violation of privacy. For VOA Special English, I'm Alex Villarreal.