Non-line-of-sight (NLOS) imaging techniques use light that diffusely reflects off of visible surfaces (e.g., walls) to see around corners. One approach involves using pulsed lasers and ultrafast sensors to measure the travel time of multiply scattered light. Unlike today's NLOS techniques that generally require densely raster scanning points across the entirety of a relay wall, we explore a more efficient form of NLOS scanning that reduces both acquisition times and computational requirements. We propose a circular and confocal non-line-of-sight (C2NLOS) scan that involves illuminating and imaging a common point, and scanning this point in a circular path along a wall. We observe that (1) these C2NLOS measurements consist of a superposition of sinusoids, which we refer to as a transient sinogram, (2) there exists computationally efficient reconstruction procedures that transform these sinusoidal measurements into 3D positions of hidden scatterers or NLOS images of hidden objects, and (3) despite operating on an order of magnitude fewer measurements than previous approaches, these C2NLOS scans provide sufficient information about the hidden scene to solve these different NLOS imaging tasks. We demonstrate results using C2NLOS measurements from both simulated and real data.

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Bibtex

@InProceedings{Isogawa_2020_ECCV,
author = {Isogawa, Mariko and Chan, Dorian and Yuan, Ye and Kitani, Kris M. and O'Toole, Matthew},
title = {Efficient Non-Line-of-Sight Imaging from Transient Sinograms},
booktitle = {16th European Conference on Computer Vision (ECCV)},
year = {2020},
pages={}
}