Query Quantized Neural SLAM

TL;DR

This paper introduces query quantized neural SLAM, a method that uses quantized input queries to enable faster and more accurate overfitting of neural implicit representations for improved SLAM performance.

Contribution

The paper proposes a novel quantization approach for neural SLAM that reduces input variation, enabling rapid overfitting and improved accuracy in camera tracking and reconstruction.

Findings

Outperforms recent methods in reconstruction quality.

Achieves more accurate camera pose estimation.

Demonstrates faster convergence in SLAM tasks.

Abstract

Neural implicit representations have shown remarkable abilities in jointly modeling geometry, color, and camera poses in simultaneous localization and mapping (SLAM). Current methods use coordinates, positional encodings, or other geometry features as input to query neural implicit functions for signed distances and color which produce rendering errors to drive the optimization in overfitting image observations. However, due to the run time efficiency requirement in SLAM systems, we are merely allowed to conduct optimization on each frame in few iterations, which is far from enough for neural networks to overfit these queries. The underfitting usually results in severe drifts in camera tracking and artifacts in reconstruction. To resolve this issue, we propose query quantized neural SLAM which uses quantized queries to reduce variations of input for much easier and faster overfitting a frame. To this end, we quantize a query into a discrete representation with a set of codes, and only allow neural networks to observe a finite number of variations. This allows neural networks to become increasingly familiar with these codes after overfitting more and more previous frames. Moreover, we also introduce novel initialization, losses, and argumentation to stabilize the optimization with significant uncertainty in the early optimization stage, constrain the optimization space, and estimate camera poses more accurately. We justify the effectiveness of each design and report visual and numerical comparisons on widely used benchmarks to show our superiority over the latest methods in both reconstruction and camera tracking.