Learning Binary Features Online from Motion Dynamics for Incremental Loop-Closure Detection and Place Recognition

TL;DR

This paper introduces an online learning method for binary visual features based on motion dynamics, enhancing loop-closure detection and place recognition with improved accuracy and efficiency.

Contribution

It presents a novel online learning algorithm for binary features that incorporates temporal consistency, improving place recognition performance in incremental systems.

Findings

Outperforms state-of-the-art methods in precision and recall

Maintains high runtime efficiency

Provides theoretical justification for learned codewords

Abstract

This paper proposes a simple yet effective approach to learn visual features online for improving loop-closure detection and place recognition, based on bag-of-words frameworks. The approach learns a codeword in bag-of-words model from a pair of matched features from two consecutive frames, such that the codeword has temporally-derived perspective invariance to camera motion. The learning algorithm is efficient: the binary descriptor is generated from the mean image patch, and the mask is learned based on discriminative projection by minimizing the intra-class distances among the learned feature and the two original features. A codeword for bag-of-words models is generated by packaging the learned descriptor and mask, with a masked Hamming distance defined to measure the distance between two codewords. The geometric properties of the learned codewords are then mathematically justified. In addition, hypothesis constraints are imposed through temporal consistency in matched codewords, which improves precision. The approach, integrated in an incremental bag-of-words system, is validated on multiple benchmark data sets and compared to state-of-the-art methods. Experiments demonstrate improved precision/recall outperforming state of the art with little loss in runtime.