Deep Non-Line-of-Sight Reconstruction

Javier Grau Chopite, Matthias B. Hullin, Michael Wand, Julian Iseringhausen
Proc. IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2020.

Abstract

The recent years have seen a surge of interest in methods for imaging beyond the direct line of sight. The most prominent techniques rely on time-resolved optical impulse responses, obtained by illuminating a diffuse wall with an ultrashort light pulse and observing multi-bounce indirect reflections with an ultrafast time-resolved imager. Reconstruction of geometry from such data, however, is a complex non-linear inverse problem that comes with substantial computational demands. In this paper, we employ convolutional feed-forward networks for solving the reconstruction problem efficiently while maintaining good reconstruction quality. Specifically, we devise a tailored autoencoder architecture, trained end-to-end, that maps transient images directly to a depth map representation. Training is done using an efficient transient renderer for diffuse three-bounce indirect light transport that enables the quick generation of large amounts of training data for the network. We examine the performance of our method on a variety of synthetic and experimental datasets and its dependency on the choice of training data and augmentation strategies, as well as architectural features. We demonstrate that our feed-forward network, even though it is trained solely on synthetic data, generalizes to measured data from SPAD sensors and is able to obtain results that are competitive with model-based reconstruction methods.

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BibTeX Citation

@InProceedings{GrauCVPR2020, author = {Javier Grau Chopite and Matthias B. Hullin and Michael Wand and Julian Iseringhausen}, title = {Deep Non-Line-of-Sight Reconstruction}, booktitle = {IEEE Conference on Computer Vision and Pattern Recognition (CVPR)}, year = {2020}, month = {June}, }