Totems: Physical Objects for Verifying Visual Integrity

AbstractWe introduce a new approach to image forensics: placing physical refractive objects, which we call totems, into scene so as protect any photograph taken of that scene. Totems bend and redirect light rays, thus providing multiple, albeit distorted, views the within single image. A defender can use these distorted totem pixels detect if an has been manipulated. Our unscrambles rays passing through totems by estimating their positions in using known geometric material properties. To verify totem-protected image, inconsistencies between reconstructed from viewpoints scene’s appearance camera viewpoint. Such makes adversarial manipulation task more difficult, adversary must modify both geometrically consistent manner without knowing properties totem. Unlike prior learning-based approaches, our method does not require training on datasets specific manipulations, instead uses solve forensics problem.