Scientists can now work out which specific camera make and model a photo was taken on. Researchers at the Polytechnic University in Brooklyn, New York, have discovered that digital cameras leave a fingerprint in the pixels of every image taken. If this proves viable in further testing it could be used by forensic scientists in kidnap situations. Photos of the victim taken by the kidnapper could be traced back to the camera it was taken on and then this information could be used to find out where the camera was purchased and by who.
The system works as every digital camera has demosaicing software that translates each pixel into usable brightness and colours. According to the research team the demosaicing software is made specifically for a particular camera type and the software algorithms are designed to work out what colour a particular screen pixel should be without clashing with the other neighbouring pixels colours.
Nasir Memon and his team have found a way to work backwards through theses neighbouring pixel values to discover which model-specific algorithm made it.
Early tests have show the technique can identify cameras with a 90% accuracy and further tests are to be carried out to collect more data.