Papers › Patch-NetVLAD: Multi-Scale Fusion of Locally-Global Descriptors for Place Recognition

Patch-NetVLAD: Multi-Scale Fusion of Locally-Global Descriptors for Place Recognition

2 Mar 2021CVPR 2021 1arXiv:2103.01486archive 2025-07-28

Stephen Hausler, Sourav Garg, Ming Xu, Michael Milford, Tobias Fischer

Visual Place Recognition is a challenging task for robotics and autonomous systems, which must deal with the twin problems of appearance and viewpoint change in an always changing world. This paper introduces Patch-NetVLAD, which provides a novel formulation for combining the advantages of both local and global descriptor methods by deriving patch-level features from NetVLAD residuals. Unlike the fixed spatial neighborhood regime of existing local keypoint features, our method enables aggregation and matching of deep-learned local features defined over the feature-space grid. We further introduce a multi-scale fusion of patch features that have complementary scales (i.e. patch sizes) via an integral feature space and show that the fused features are highly invariant to both condition (season, structure, and illumination) and viewpoint (translation and rotation) changes. Patch-NetVLAD outperforms both global and local feature descriptor-based methods with comparable compute, achieving state-of-the-art visual place recognition results on a range of challenging real-world datasets, including winning the Facebook Mapillary Visual Place Recognition Challenge at ECCV2020. It is also adaptable to user requirements, with a speed-optimised version operating over an order of magnitude faster than the state-of-the-art. By combining superior performance with improved computational efficiency in a configurable framework, Patch-NetVLAD is well suited to enhance both stand-alone place recognition capabilities and the overall performance of SLAM systems.

PaperPDFConference PDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2103.01486")

Code

Syntology Ran 4 of 5 code samples harvested from 2 repositories linked to this paper; 1 has no recorded run. Of those that ran: 1 ran · our draft was wrong; 1 ran · fixture could not drive it; 2 ran with no contract checked.

By repository: official repository: 3 samples from 1 repository, 3 ran; community (archive-listed): 2 samples from 1 repository, 1 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

QVPR/Patch-NetVLAD officialmentioned in papermentioned on GitHubpytorch report
taowenyin/PatchNetVLAD mentioned on GitHubpytorch report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

5 samples harvested; 4 ran; 0 honoured the contract we drafted; 1 has no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

1ran · our draft was wrong
1ran · fixture could not drive it
2ran
1unverified

Licence: 0 of the 5 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from 2 repositories linked to this paper, official or community; each sample names its own and says which. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

PatchNetVLAD QVPR/Patch-NetVLAD/patchnetvlad/models/patchnetvlad.py official repository ran fingerprinted MIT (permissive) · 3df22a709177cb8f · report
get_integral_feature QVPR/Patch-NetVLAD/patchnetvlad/models/patchnetvlad.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · 9402f303f3ae9ff0 · report
get_square_regions_from_integral QVPR/Patch-NetVLAD/patchnetvlad/models/patchnetvlad.py official repository ran · fixture could not drive it MIT (permissive) · d8abdf376063a44c · report
get_square_regions_from_integral taowenyin/PatchNetVLAD/patchnetvlad/models/patchnetvlad.py community (archive-listed) ran fingerprinted MIT (permissive) · d062e48ac9b786f0 · report
PatchNetVLAD taowenyin/PatchNetVLAD/patchnetvlad/models/patchnetvlad.py community (archive-listed) unverified MIT (permissive) · 044ac142e4307cc8 · report

Tasks

Computational EfficiencyVisual LocalizationVisual Place Recognition

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Visual Localization Extended CMU Seasons Patch-NetVLAD Acc @ .25m, 2° 0.118 #1 of 1 Archive leaderboard report
Visual Localization Extended CMU Seasons Patch-NetVLAD Acc @ .5m, 5° 0.362 #1 of 1 Archive leaderboard report
Visual Localization Extended CMU Seasons Patch-NetVLAD Acc @ 5m, 10° 0.962 #1 of 1 Archive leaderboard report
Visual Localization RobotCar Seasons v2 Patch-NetVLAD Acc @ .25m, 2° 0.096 #1 of 1 Archive leaderboard report
Visual Localization RobotCar Seasons v2 Patch-NetVLAD Acc @ .5m, 5° 0.353 #1 of 1 Archive leaderboard report
Visual Localization RobotCar Seasons v2 Patch-NetVLAD Acc @ 5m, 10° 0.909 #1 of 1 Archive leaderboard report
Visual Place Recognition Mapillary val Patch-NetVLAD Recall@1 79.5 #16 of 18 Archive leaderboard report
Visual Place Recognition Mapillary val Patch-NetVLAD Recall@10 87.7 #16 of 18 Archive leaderboard report
Visual Place Recognition Mapillary val Patch-NetVLAD Recall@5 86.2 #16 of 18 Archive leaderboard report
Visual Place Recognition Nordland Patch-NetVLAD Recall@1 58.4 #10 of 13 Archive leaderboard report
Visual Place Recognition Nordland Patch-NetVLAD Recall@5 74.6 #10 of 13 Archive leaderboard report
Visual Place Recognition Pittsburgh-30k-test Patch-NetVLAD Recall@1 88.7 #16 of 22 Archive leaderboard report
Visual Place Recognition Pittsburgh-30k-test Patch-NetVLAD Recall@5 94.5 #16 of 22 Archive leaderboard report
Visual Place Recognition Tokyo247 Patch-NetVLAD Recall@1 86 #11 of 14 Archive leaderboard report
Visual Place Recognition Tokyo247 Patch-NetVLAD Recall@10 90.5 #11 of 14 Archive leaderboard report
Visual Place Recognition Tokyo247 Patch-NetVLAD Recall@5 88.6 #11 of 14 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections