Digital Home Thoughts: Digital Image Fingerprints

"Fridrich's technique is rooted in the discovery by her research group of this simple fact: Every original digital picture is overlaid by a weak noise-like pattern of pixel-to-pixel non-uniformity. Although these patterns are invisible to the human eye, the unique reference pattern or "fingerprint" of any camera can be electronically extracted by analyzing a number of images taken by a single camera. That means that as long as examiners have either the camera that took the image or multiple images they know were taken by the same camera, an algorithm developed by Fridrich and her co-inventors to extract and define the camera's unique pattern of pixel-to-pixel non-uniformity can be used to provide important information about the origins and authenticity of a single image."

An interesting article about how every digital camera has a unique signature, and how it might be used to track images that are illegal (such as child pornography). I often wonder what the impact will be once search engines can index photos, videos, and audio the same way they can index text. There's so much digital media out there now, when someone finds a way to index and cross-reference all of it, things might get uncomfortable.