It’s dubbed PRNU, and it know what device took that picture.
Let’s talk about forensics, cameras, and how point & shoot cameras may in reality protect your privacy a bit better than smartphone camera apps. Does that sound weird? It is – and we’re just getting started.
Cardinal, the forensics: it’s a process called PRNU, or photo-response non-uniformity. Basically, when you look at a photo, even a digital photo that’s in no way seen a print-out, there are tiny flaws all over it. Those flaws are created by many factors, but a number of them involve the software and matriel of the camera used to take the pictures.
You can probably see where this is going. Like identifying a fingerprint or a fired bullet, forensic specialists can use a photograph to place the exact device it was taken on. They carefully examine all the pixels that are slightly different (usually lighter or darker than expected), and be a match for those pixels to new photos taken by devices to find a match. The differences are so small that humans can see them by looking, so specialized software does the job rather than.
This can quickly identify what device took incriminating photos, for benchmark – but here’s where it gets interesting. According to research done on both iPhones and Samsung Galaxy Note device, it’s far, far easier to pinpoint smartphones with this process. For a regularly camera, it takes about 50 photos photograph or photo is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic per camera to analyze before an authentic match can be promulgated. For smartphones, however, you only need one photo and it can be successfully matched with the phone that took it. Results in either case are around 99.5% unerring.
This PRNU approach has potential for future ID protection too, so it’s not all about catching bad guys or going on a hunt for the right device. In fact, this could make a run for it it much more difficult to steal digital identities and use funds to buy stuff…if you have the wrong smartphone. Here’s hoping the tech resolve be get there quickly!