Scientist devises way to tell if an image has been "Photoshopped"
Hany Farid, a Dartmouth College computer scientist and forensic imaging specialist, is developing a digital forensics software that can determine the authenticity of photos, Bloomberg Businessweek reported last month. The software can also tell the make and model of the camera used to take the photo. Farid, 44, said, "(It’s) exactly like gun ballistics... If Photoshop touches that image, we will know about it."
Using images taken with permission from photo-sharing website Flickr, Farid and his students are building a database of electronic signatures of over 10,000 digital camera models. To check a photo’s authenticity, Farid’s system identifies the camera model that captured the picture. Then, it looks for signature variations and traces of the editing software Adobe Photoshop, which also leaves a signature.
Bloomberg Businessweek noted that Farid’s software has a limitation: it does not show exactly what was altered and how. Other techniques like 3D modeling software are needed to answer such queries.
For more on this story, log on to Bloomberg Businessweek.