3QFP: Efficient neural implicit surface reconstruction using Tri-Quadtrees and Fourier feature Positional encoding

Shuo Sun, Malcolm Mielle, Achim J. Lilienthal and Martin Magnusson
Proceedings of 2024 IEEE International Conference on Robotics and Automation (ICRA)

 

Abstract

Neural implicit surface representations are currently receiving a lot of interest as a means to achieve high-fidelity surface reconstruction at a low memory cost, compared to traditional explicit representations. However, state-of-the-art methods still struggle with excessive memory usage and non-smooth surfaces. This is particularly problematic in large-scale applications with sparse inputs, as is common in robotics use cases. To address these issues, we first introduce a sparse structure, tri-quadtrees, which represents the environment using learnable features stored in three planar quadtree projections. Secondly, we concatenate the learnable features with a Fourier feature positional encoding. The combined features are then decoded into signed distance values through a small multilayer perceptron. We demonstrate that this approach facilitates smoother reconstruction with a higher completion ratio with fewer holes. Compared to two recent baselines, one implicit and one explicit, our approach requires only 10%–50% as much memory, while achieving competitive quality. The code is released on https://github.com/ljjTYJR/3QFP.

@INPROCEEDINGS{10610338, 
author={Sun, Shuo and Mielle, Malcolm and Lilienthal, Achim J. and Magnusson, Martin}, 
booktitle={2024 IEEE International Conference on Robotics and Automation (ICRA)}, 
title={3QFP: Efficient neural implicit surface reconstruction using Tri-Quadtrees and Fourier feature Positional encoding}, 
year={2024}, 
volume={}, 
number={}, 
pages={4036-4044}, 
keywords={Surface reconstruction;Costs;Codes;Memory management;Multilayer perceptrons;Encoding;Robots}, 
doi={10.1109/ICRA57147.2024.10610338}
}