Start-up company Fourandsix Technologies, cofounded by Dartmouth College computer scientist Hany Farid, is developing software that will determine whether a photo has been altered since it was first taken - and if so, how.
“We’re in the business of trying to really think like a forger,’’ Farid said.
For example, he tries to think of ways that a forger intent on deleting an object from a photo, or adding one, might leave traces in the image; maybe the way the light falls on the people in the photo from subtly different angles will not be taken into account.
Farid said the company’s first product, software that will be able to tell what kind of camera took a photo and whether it has been altered since it was taken, will be available in March.
The field has taken off, in part because the photos people pass around so easily in saved files have unique digital fingerprints - a distinct signature that is created when a photo is taken.
“You may see a picture - it may be a mountain or a person. What I see is the computational trace,’’ said Ray Liu, a professor of information technology at the University of Maryland, who is also developing techniques to detect that an image has been altered. He added that such technology has become of great interest to the military.
In a very different arena - advertising and magazines - photo manipulation has become increasingly important, because it can create unrealistic visions of body image.
The problem was recognized this summer by the American Medical Association, which officially adopted a policy to discourage advertisers from altering photos in ways that could create unhealthy expectations among vulnerable adolescents. Two years ago, a Ralph Lauren ad came under fire for showing a freakishly thin, digitally altered version of model Filippa Hamilton.
