Via NY Times:
A college professor and former Adobe executive have launched a start-up whose first product will likely strike fear into the hearts of hoaxers everywhere: FourMatch. The program is designed to discover signs that an image has been altered by the popular image editing software Photoshop. The program’s creators envision law enforcement and photography professionals to be FourMatch’s primary customers. Here’s how it works:
Fourandsix’s downloadable software, FourMatch, determines the likelihood that an image has been altered by comparing the digital “signature” of an image with a database of more than 70,000 known signatures for cameras, smartphones, software and online services, from social networks like Facebook to photo-storing sites like Picasa. The software tells the user if an image matches a known signature or has been modified by software and can suggest how extensive the alteration may have been. FourMatch works as an extension to Photoshop.
FourMatch sounds like it could be useful, but how long will it take for someone to invent another program to defeat it?