Researchers at the University of Buffalo have discovered a way to identify smartphones - by the photos they take. It uses a flaw in digital images, similar to how police ballistics reports work.
This flaw, called photo-response non-uniformity (PRNU) occurs because the manufacturing process is imprecise. This creates minuscule variations between one camera’s sensors and another, that cause unique brighter or darker patterns in the images they click. Though these are invisible to the naked eye, a computer can spot these patterns.
“Like snowflakes, no two smartphones are the same,” Kui Ren, the study’s lead author, said in a statement. “Each device, regardless of the manufacturer or make, can be identified through a pattern of microscopic imaging flaws that are present in every picture they take. It’s kind of like matching bullets to a gun, only we’re matching photos to a smartphone camera.”