Dartmouth computer science professor Hany Farid's recent software startup, photo forensics company Fourandsix Technologies, released software product FourMatch on Sept. 18. FourMatch, the company's first product to be released, allows law enforcement officers and other professionals to confirm whether or not a digital image has been altered for use as evidence while also maintaining journalistic integrity.
After researching and developing in the area of digital forensics for 13 years at Dartmouth, Farid partnered with Photoshop veteran and Adobe Vice President Kevin Connor to develop the technology for professional use.
Farid said that target audiences include law enforcement and media agencies, which can use the software to authenticate images presented as evidence or factual accounts. By requiring journalists to submit the original photograph and then testing its authenticity with FourMatch, news agencies can avoid manipulation scandals, Eric Kee GR '12, a graduate student who has been working with Farid for five years, said. When photographs are used as evidence in legal cases, there must be proof that they are unaltered, he added.
FourMatch is also marketed for online businesses. Where photographs are essential for the online service being provided, the ability to authenticate photographs is extremely important, Farid said. For insurance agencies and companies like eBay, the value of a product or damage is determined through photographs, and determining the accuracy of these images is crucial.
Since the product's release last week, Fourandsix has completed one sale and has three to four more sales pending, Farid said.
As the technology becomes more streamlined, Fourandsix may add an online service that would allow people to upload photographs and assess their accuracy, Farid said. He said he hopes to eventually expand the software for use by "everyday people who are just curious about the authenticity of photos."
In contrast to Farid's other work, FourMatch determines authenticity but does not provide information about the extent of the edits. The program checks a photograph's metadata, or "signature," which includes information about its creation and format, against the signatures produced by a variety of cameras, according to Kee.
"When you modify or hit save, the format of the photo gets changed," Kee said. "You can look at metadata information in the photo and ask, Do we know of any camera that produces that information?' If no, we know that photo has been re-saved."
FourMatch examines the photograph's file itself, which is one of multiple ways to analyze its authenticity, Kee said. Traces of the editing process, such as color inconsistencies or halos around shadows, are also useful in authenticating the photograph. A signature match through FourMatch confirms originality, but no match is ambiguous, so these other elements can be used for clarification, he added.
"If you're pasting photos together, the shadows might be going all different directions that aren't coherent," Kee said.
FourMatch is priced at $890, which is standard for this type of professional-level software, according to Farid.
Fourandsix plans to develop tools for analyzing other elements of the photographs in the future, Connor wrote on the company's blog. Kee said that the name for the company, Fourandsix, comes from Farid's play on the word "forensics."
Farid is the leader in digital forensic science and has helped to establish the field through his work in developing systems to rate images in magazines, according to Kee.
"Farid sets a very high bar on the work that he does," Kee said. "This technology that Fourandsix is developing, it's the real deal. It really works."
