Exposing Digital Forgeries in Complex Lighting Environments
IEEE Transactions on Information Forensics and Security, 2007
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Abstract
The availability of sophisticated digital imaging technology has given rise to digital forgeries that are increasing in sophistication and frequency. We describe a technique for exposing such fakes by detecting inconsistencies in lighting. We show how to approximate complex lighting environments with a low-dimensional model and how to estimate the model parameters from a single image. Inconsistencies in the lighting model are then used as evidence of tampering.