The New York Times reports on the broad issue of authenticating digital photographs, as well as efforts by researchers at Dartmouth College to develop methods for verifying whether a digital image has ever been altered.

The article also describes research at SUNY Binghamton that has shown that digital cameras leave distinct signatures in the images they capture, similar to the way that rifle barrels leave unique markings on bullets that they fire. At the behest of the U.S. Air Force, the Binghamton researchers are also developing a camera that can capture an image of the photographer's iris and embed it into pictures captured by the camera, thereby linking digital photos with the person who shot them.

(The article should be available online for free until July 29, 2004.)