๐ค AI Summary
This work addresses the challenges of perceptual ambiguity caused by irrelevant image regions and inefficient re-ranking due to rigid candidate scheduling in visual place recognition. To this end, the authors propose FoL++, a method that introduces a spatial reliability map to model occlusion robustness, integrates weakly supervised pseudo-correspondence learning, and employs an adaptive candidate scheduling mechanism to dynamically refine the candidate pool and fuse global-local matching evidence. Leveraging a lightweight architecture and two novel spatial alignment lossesโSpatial Alignment Loss (SAL) and Spatial Correspondence Enhancement Loss (SCEL)โFoL++ achieves state-of-the-art performance across seven benchmarks, delivering a 40% improvement in inference speed over FoL while maintaining low memory overhead.
๐ Abstract
Visual Place Recognition (VPR) determines a query image's geographic location by matching it against geotagged databases. However, existing methods struggle with perceptual aliasing caused by irrelevant regions and inefficient re-ranking due to rigid candidate scheduling. To address these issues, we introduce FoL++, a method combining robust discriminative region modeling with adaptive re-ranking. Specifically, we propose a Reliability Estimation Branch to generate spatial reliability maps that explicitly model occlusion resistance. This representation is further optimized by two spatial alignment losses (SAL and SCEL) to effectively align features and highlight salient regions. For weakly supervised learning without manual annotations, a pseudo-correspondence strategy generates dense local feature supervision directly from aggregation clusters. Our Adaptive Candidate Scheduler dynamically resizes candidate pools based on global similarity. By weighting local matches by reliability and adaptively fusing global and local evidence, FoL++ surpasses traditional independent matching systems. Extensive experiments across seven benchmarks demonstrate that FoL++ achieves state-of-the-art performance with a lightweight memory footprint, improving inference speed by 40% over FoL. Code and models will be released (and merged with FoL) at https://github.com/chenshunpeng/FoL.