“Real-time Non-line-of-sight Imaging” by O’Toole, Lindell and Wetzstein

  • ©Matthew O’Toole, David B. Lindell, and Gordon Wetzstein


    Real-time Non-line-of-sight Imaging


Entry Number: 15


    Non-line-of-sight (NLOS) imaging aims at recovering the shape of objects hidden outside the direct line of sight of a camera. In this work, we report on a new approach for acquiring time-resolved measurements that are suitable for NLOS imaging. The system uses a confocalized single-photon detector and pulsed laser. As opposed to previously-proposed NLOS imaging systems, our setup is very similar to LIDAR systems used for autonomous vehicles and it facilitates a closed-form solution of the associated inverse problem, which we derive in this work. This algorithm, dubbed the Light Cone Transform, is three orders of magnitude faster and more memory efficient than existing methods. We demonstrate experimental results for indoor and outdoor scenes captured and reconstructed with the proposed confocal NLOS imaging system.


    Mauro Buttafava, Jessica Zeman, Alberto Tosi, Kevin Eliceiri, and Andreas Velten. 2015. Non-line-of-sight imaging using a time-gated single photon avalanche diode. Opt. Express 23, 16 (2015), 20997–21011.
    Otkrist Gupta, Thomas Willwacher, Andreas Velten, Ashok Veeraraghavan, and Ramesh Raskar. 2012. Reconstruction of hidden 3D shapes using diffuse reflections. Opt. Express 20, 17 (2012), 19096–19108.

    Felix Heide, Lei Xiao,Wolfgang Heidrich, and Matthias B. Hullin. 2014. Diffuse mirrors: 3D reconstruction from diffuse indirect illumination using inexpensive time-offlight sensors. Proc. CVPR (2014), 3222–3229.

    Ahmed Kirmani, Tylor Hutchison, James Davis, and Ramesh Raskar. 2009. Looking around the corner using transient imaging. Proc. ICCV (2009), 159–166.

    MatthewO’Toole, Felix Heide, David B. Lindell, Kai Zang, Steven Diamond, and Gordon Wetzstein. 2017. Reconstructing transient images from single-photon sensors. Proc. CVPR (2017).

    Matthew O’Toole, David B. Lindell, and Gordon Wetzstein. 2018. Confocal non-lineof-sight imaging based on the light-cone transform. Nature 555 (2018), 338–341.

    Andreas Velten, Thomas Willwacher, Otkrist Gupta, Ashok Veeraraghavan, Moungi G. Bawendi, and Ramesh Raskar. 2012. Recovering three-dimensional shape around a corner using ultrafast time-of-flight imaging. Nature Communications 3 (2012).

    Di Wu, Gordon Wetzstein, Christopher Barsi, Thomas Willwacher, Matthew O’Toole, Nikhil Naik, Qionghai Dai, Kyros Kutulakos, and Ramesh Raskar. 2012. Frequency analysis of transient light transport with applications in bare sensor imaging. Proc. ECCV (2012), 542–555.

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©Matthew O’Toole, David B. Lindell, and Gordon Wetzstein ©Matthew O’Toole, David B. Lindell, and Gordon Wetzstein ©Matthew O’Toole, David B. Lindell, and Gordon Wetzstein

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