In August, the New York Times reported on questions about personal privacy that can arise from “geotagging” photographs or videos — embedding GPS location data — and then publishing those photos on Web sites or social-networking services such as Twitter or Facebook. Also in August, USA Today focused on the issue of privacy and location-tracking services.
Now, CNN takes a look at how technology can reveal private location information without a person’s knowledge.
Images often contain a bundle of information and various traces left by digital cameras or photo manipulation software. This data, called Exchangeable Image File Format (EXIF), is a key tool for many professionals. It can detail whether the photographer used a flash, which digital effects were applied to a picture and when the photo was taken.
EXIF can also contain the precise GPS coordinates for where a photo was taken. This information is readily accessible and can be plugged into software such as Google Maps — leading some security and photography experts to express concerns about amateurs unknowingly disclosing private information, such as the location of their home. […]
Thomas Hawk, an active Flickr user and the former chief executive of competing photo site Zooomr, said EXIF is an important part of his archival process. But he has also used that data to track down someone who was harassing him online and managed to coerce an apology, he said.
“I don’t geotag any pictures to my house,” Hawk said on the phone last week. “I think it’s a huge concern. I think a lot of people don’t realize or recognize what’s in all of the EXIF data that they’re publishing.” […]
Some photo services, including Facebook, TwitPic and Yfrog, strip EXIF once a file is uploaded and don’t offer a way for users to access the original.
For Yfrog, the lack of EXIF is a byproduct of automatic image optimizations done by the system, not something designed specifically with privacy in mind, Mike Harkey, a spokesman for the ImageShack-owned Yfrog site, wrote in an e-mail.