ResFields: Residual Neural Fields for Spatiotemporal Signals
Authors: name: Marko Mihajlovic, name: Sergey Prokudin, name: Marc Pollefeys, name: Siyu Tang

Neural fields, a category of neural networks trained to represent
high-frequency signals, have gained significant attention in recent years due
to their impressive performance in modeling complex 3D data, especially large
neural signed distance (SDFs) or radiance fields (NeRFs) via a single
multi-layer perceptron (MLP). However, despite the power and simplicity of
representing signals with an MLP, these methods still face challenges when
modeling large and complex temporal signals due to the limited capacity of
MLPs. In this paper, we propose an effective approach to address this
limitation by incorporating temporal residual layers into neural fields, dubbed
ResFields, a novel class of networks specifically designed to effectively
represent complex temporal signals. We conduct a comprehensive analysis of the
properties of ResFields and propose a matrix factorization technique to reduce
the number of trainable parameters and enhance generalization capabilities.
Importantly, our formulation seamlessly integrates with existing techniques and
consistently improves results across various challenging tasks: 2D video
approximation, dynamic shape modeling via temporal SDFs, and dynamic NeRF
reconstruction. Lastly, we demonstrate the practical utility of ResFields by
showcasing its effectiveness in capturing dynamic 3D scenes from sparse sensory
inputs of a lightweight capture system.