Tungstène is an application used to detect digital image manipulation. It's a heavy-weight mathematical engine with a GUI front-end. It doesn't only rely on metadata or other tamper-sensitive information in the image, but mainly analyses the image itself. Erik Vlietinck reports.
Used by press agencies, forensic institutes and the military, Tungstène is currently looking for a somewhat broader distribution network, but its French developer and patent owner Roger Cozien, states quite specifically that this is no software for end-users. It requires at least one full week of training before you can work with it. When you can, you can tell with virtually 100% confidence an image has been altered digitally.
Agence Presse, France, uses Tungstène to check whether what is depicted by a photo is was really there when the photographer shot the image, or whether elements have been added or left out.
Tungstène can do more, though.
It will also show areas that have been retouched. If part of a face has been shadow-lifted because of cosmetic reasons, the software will show the affected area in bright colours.
While Tungstène can show whether a photograph has been tampered with, and which areas have been affected, it can't interpret the results. For example, when a shot of three F16s shows one of them lacks the invisible heat footprint that real F16s produce in the vapour trail, the interpretation is easy: that one plane has been digitally added.
When Tungstène shows a shadow area has been altered, the interpretation becomes more of a puzzle: was it changed because of cosmetic reasons, or to emphasise the person's importance by making her stand out more?
The interpretation part and the rather complicated filter technology used in Tungstène makes it software that requires training. Cozien and his firm eXo Makina are already working on a video version. In 2013, Tungstène is set to conquer the US.
Tungstène's power: A photo of Kate Middleton proves to be fake. The software reveals the full head and hair have been "Photoshopped" on someone else's body.
The software also detected an edited square right in the middle of the chest. Cozien used the app's multispectral tools to find these "retouches".