Descattering Transmission via Angular Filtering

Abstract

We describe a single-shot method to differentiate unscattered and scattered components of light transmission through a heterogeneous translucent material. Directly-transmitted components travel in a straight line from the light source, while scattered components originate from multiple scattering centers in the volume. Computer vision methods deal with participating media via 2D contrast enhancing software techniques. On the other hand, optics techniques treat scattering as noise and use elaborate methods to reduce the scattering or its impact on the direct unscattered component. We observe the scattered component on its own provides useful information because the angular variation is low frequency. We propose a method to strategically capture angularly varying scattered light and compute the unscattered direct component. We capture the scattering from a single light source via a lenslet array placed close to the image plane. As an application, we demonstrate enhanced tomographic reconstruction of scattering objects using estimated direct transmission images.