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Real-time non-line-of-sight computational imaging using spectrum filtering and motion compensation

Abstract

Non-line-of-sight (NLOS) imaging aims at recovering the shape and albedo of hidden objects. Despite recent advances, real-time video of complex and dynamic scenes remains a major challenge owing to the weak signal of multiply scattered light. Here we propose and demonstrate a framework of spectrum filtering and motion compensation to realize high-quality NLOS video for room-sized scenes. Spectrum filtering leverages a wave-based model for denoising and deblurring in the frequency ___domain, enabling computational image reconstruction with a small number of sampling points. Motion compensation tailored with an interleaved scanning scheme can compute high-resolution live video during the acquisition of low-quality image sequences. Together, we demonstrate live NLOS videos at 4 fps for a variety of dynamic real-life scenes. The results mark a substantial stride toward real-time, large-scale and low-power NLOS imaging and sensing applications.

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Fig. 1: The NLOS imaging set-up.
Fig. 2: Method comparisons.
Fig. 3: The interleaved scanning scheme.
Fig. 4: NLOS live videos of real-world dynamic scenes.
Fig. 5: Live NLOS video of real-world dynamic scenes.
Fig. 6: Ablation study.

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Data availability

Source data for Figs. 26 are available with this paper. The datasets collected by the imaging system can be accessed from Code Ocean at https://doi.org/10.24433/CO.2487919.v2 (ref. 48).

Code availability

The code used in the current study can be accessed from Code Ocean at https://doi.org/10.24433/CO.2487919.v2 (ref. 48).

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Acknowledgements

This work was supported by the Innovation Program for Quantum Science and Technology (2021ZD0300300), the National Natural Science Foundation of China (grant number 62031024), the Shanghai Municipal Science and Technology Major Project (2019SHZDZX01), the Shanghai Science and Technology Development Funds (22JC1402900), the Shanghai Academic/Technology Research Leader (21XD1403800), the Anhui Initiative in Quantum Information Technologies, Chinese Academy of Sciences, and the New Cornerstone Science Foundation through the Xplorer Prize.

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Authors and Affiliations

Authors

Contributions

F.X., X.D. and J.-W.P. conceived of the research. J.-T.Y., Y.S. and F.X. performed the experiments and data processing. J.-T.Y., Y.S. and W.L. implemented the reconstruction algorithms and analyzed the data, with input from all authors. J.-T.Y., Y.S., J.-W.Z. and Z.-P.L. calibrated the imaging system. J.-T.Y., F.X. and J.-W.P. wrote the paper, with input from all authors. All authors contributed materials and analysis tools.

Corresponding author

Correspondence to Feihu Xu.

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Peer review information

Nature Computational Science thanks Christopher Metzler, Andreas Velten and Jingyi Yu for their contribution to the peer review of this work. Primary Handling Editor: Jie Pan, in collaboration with the Nature Computational Science team.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–18, Notes 1–12 and Tables 1–7.

Supplementary Video 1

Introduction video.

Supplementary Video 2

Imaging results (Fig. 4).

Supplementary Video 3

Imaging results (Fig. 5).

Supplementary Video 4

Imaging results (Fig. 6).

Supplementary Video 5

Imaging results (Supplementary Fig. 11).

Source data

Source Data Fig. 2

Reconstruction results of algorithm.

Source Data Fig. 3

Reconstruction results of algorithm.

Source Data Fig. 4

Reconstruction results of algorithm.

Source Data Fig. 5

Reconstruction results of algorithm.

Source Data Fig. 6

Reconstruction results of algorithm.

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Ye, JT., Sun, Y., Li, W. et al. Real-time non-line-of-sight computational imaging using spectrum filtering and motion compensation. Nat Comput Sci 4, 920–927 (2024). https://doi.org/10.1038/s43588-024-00722-4

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