Recovering Scene Depth and Reflectance in Dense Fog with Different Imaging Modalities

A light source may illuminate a scene that is obscured by fog. Light may reflect back to a time-resolved light sensor. For instance, the light sensor may comprise avalanche photodiodes that are not single-photon sensitive. The light sensor may perform a raster scan. The imaging system may determine reflectance and depth of the fog-obscured target. The imaging system may perform a probabilistic algorithm that exploits the fact that times of arrival of photons reflected from fog have a Gamma distribution that is different than the Gaussian distribution of times of arrival of photons reflected from the target. The imaging system may adjust frame rate locally depending on local density of fog, as indicated by a local Gamma distribution determined in a prior step. The imaging system may perform one or more of spatial regularization, temporal regularization, and deblurring.