When can a photo be trusted?

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Welcome to the Fourandsix blog, where you’ll find tips on image forensics techniques and commentary on issues relevant to photo tampering and the responsible use of imaging tools.


Join me for an AMA on reddit

I’m doing an AMA on reddit on Thursday Feb. 6 at 4:00 PM (ET). Please join me and feel free to ask anything related to image forensics, our work on photoDNA, our new photo authentication site izitru.com, or anything else that you’d like. 

For those of you that may be new to this blog, you can learn a little bit about me and my work from this NOVA episode, my blog, or my Dartmouth website.


Truth in Social Media: Starting at the Source

In this blog and through tools like FourMatch we’ve introduced methods to investigate whether or not a particular image is trustworthy. A particular challenge with investigating images, however, is that photos distributed through social media tend to be saved, resaved, and degraded multiple times, often obscuring the very information needed to conduct an effective analysis. After focusing on tools for investigators, we began to wonder what would happen if we turned the problem on its head. What if social media users could certify their images before they shared them online? What if there was a public place for them to store and share these certified images so that downstream viewers could know more definitively when an image could be trusted?

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From Possible to Practical: The Gap between Research and Product

Regular readers of this blog have learned about a diverse collection of image forensics techniques which Hany Farid and others have developed over the past decade or more. Yet Fourandsix currently offers just one commercial product featuring just one of these many techniques. Of course, this type of situation is common in technology. Any regular readers of tech blogs have no doubt seen countless articles featuring the latest innovations in research, only to discover that they’ll need to wait years to access those innovations in a product, if indeed the ideas ever get productized at all. Why is it such a bumpy road from research to final product, and what, you might ask, is Fourandsix doing to bring more technology to market?

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The Photo Of The Alleged Iranian Spy: A Followup

Last week I discussed questions surrounding the photo of an accused Iranian spy. At first glance the shadows in the photo seem somewhat odd, but a forensic shadow analysis revealed that the shadows are physically plausible. Here I show how this analysis can be further refined to provide even stronger evidence of this photo’s viability.

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Has The Alleged Iranian Spy Been Photoshopped?

Israel’s domestic intelligence service released photos of an accused Iranian spy. Questions have emerged as to the possible authenticity of the photo. At first glance, the shadows in the photo seem somewhat odd.

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