Digital image forensics

Fraudulent photographs produced with powerful, commercial software appear constantly, spurring a new field of digital image forensics. Many fakes can be exposed because of inconsistent lighting, including the specks of light reflected from people's eyeballs. Algorithms can spot when an image has a cloned area or does not have the mathematical properties of a raw digital photograph. A person's iris are circular in reality but will appear increasingly elliptical as the eyes turn to the side or up or down. One can approximate how eyes will look in a photograph by tracing rays of light running from them to a point called the camera center. Modern software has made manipulation of photographs easier to carry out and harder to uncover than ever before, but the technology also enables new methods of detecting doctored images.