Computers have long made it possible to create highly realistic fake images. Now, thanks to Izitru — a new service launched by photo forensics firm Fourandsix — those very same computers can help us automatically detect those fakes. Izitru builds on the pioneering work that imaging guru Hany Farid has done in detecting phony photos. Unlike previous systems, Izitru is completely automated, relying on a set of six tests to help verify uploaded JPEG images.
Izitru (pronounced “is it true”) builds on the JPEG signature analysis first launched in Fourandsix’s FourMatch plug-in for Photoshop. This test uses the fact that nearly every model of digital camera uses slightly different coefficients for doing the encoding and compression of its JPEG.