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FSAF

7 papers tagged archive 2025-07-28

Introduced by Chenchen Zhu et al. in Feature Selective Anchor-Free Module for Single-Shot Object Detection

archive 2025-07-28 Description, source and code snippet are the archive's method entry.

FSAF, or Feature Selective Anchor-Free, is a building block for single-shot object detectors. It can be plugged into single-shot detectors with feature pyramid structure. The FSAF module addresses two limitations brought up by the conventional anchor-based detection: 1) heuristic-guided feature selection; 2) overlap-based anchor sampling. The general concept of the FSAF module is online feature selection applied to the training of multi-level anchor-free branches. Specifically, an anchor-free branch is attached to each level of the feature pyramid, allowing box encoding and decoding in the anchor-free manner at an arbitrary level. During training, we dynamically assign each instance to the most suitable feature level. At the time of inference, the FSAF module can work jointly with anchor-based branches by outputting predictions in parallel. We instantiate this concept with simple implementations of anchor-free branches and online feature selection strategy

The general concept is presented in the Figure to the right. An anchor-free branch is built per level of feature pyramid, independent to the anchor-based branch. Similar to the anchor-based branch, it consists of a classification subnet and a regression subnet (not shown in figure). An instance can be assigned to arbitrary level of the anchor-free branch. During training, we dynamically select the most suitable level of feature for each instance based on the instance content instead of just the size of instance box. The selected level of feature then learns to detect the assigned instances. At inference, the FSAF module can run independently or jointly with anchor-based branches. The FSAF module is agnostic to the backbone network and can be applied to single-shot detectors with a structure of feature pyramid. Additionally, the instantiation of anchor-free branches and online feature selection can be various.

PaperSourceSee Code · hdjang/Feature-Selective-Anchor-Free-Module-for-Single-Shot-Object-Detection

Papers archive 2025-07-28

7 shown of 7, newest first. Repository counts are the archive's code-links table. A Syntology line states what Syntology ran from that paper's harvested code; it is per sample and not a correctness claim.

Tasks archive 2025-07-28

18 tasks the archive attaches to papers tagged with this method, by distinct papers. A task without a page in the catalog is plain text.

TaskPapers
Object Detection6
object-detection5
Action Detection1
Activity Detection1
Avg1
Bayesian Optimization1
Ensemble Learning1
FAD1
Few-Shot Learning1
Fracture detection1
Image Compression1
Instance Segmentation1
Medical Object Detection1
Meta-Learning1
Object1
Transfer Learning1
Vessel Detection1
feature selection1

Usage over time archive 2025-07-28

Papers per year tagged with FSAF: 2019 to 2024, peak 3 3 0 2019: 1 paper 2019 2020: 0 papers 2020 2021: 3 papers 2021 2022: 2 papers 2022 2023: 0 papers 2023 2024: 1 paper 2024
Papers per year the archive tags with this method, by the paper's archive date (7 dated). Bars are counts, not a trend claim.

Components: the archive holds no method-to-method composition, so PwC's Components table cannot be rebuilt; the Papers list carries no Results column for the same reason (the archive does not join its leaderboard rows to method tags).

Categories archive 2025-07-28

Feature Extractors

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