Computational Mirrors: Blind Inverse Light Transport by Deep Matrix Factorization

Aittala, Miika, Sharma, Prafull, Murmann, Lukas, Yedidia, Adam, Wornell, Gregory, Freeman, Bill, Durand, Fredo

Neural Information Processing Systems 

We recover a video of the motion taking place in a hidden scene by observing changes in indirect illumination in a nearby uncalibrated visible region. We solve this problem by factoring the observed video into a matrix product between the unknown hidden scene video and an unknown light transport matrix. This task is extremely ill-posed, as any non-negative factorization will satisfy the data. Inspired by recent work on the Deep Image Prior, we parameterize the factor matrices using randomly initialized convolutional neural networks trained in a one-off manner, and show that this results in decompositions that reflect the true motion in the hidden scene. Papers published at the Neural Information Processing Systems Conference.