Papers › Soft Anchor-Point Object Detection

Soft Anchor-Point Object Detection

27 Nov 2019ECCV 2020 8arXiv:1911.12448archive 2025-07-28

Chenchen Zhu, Fangyi Chen, Zhiqiang Shen, Marios Savvides

Recently, anchor-free detection methods have been through great progress. The major two families, anchor-point detection and key-point detection, are at opposite edges of the speed-accuracy trade-off, with anchor-point detectors having the speed advantage. In this work, we boost the performance of the anchor-point detector over the key-point counterparts while maintaining the speed advantage. To achieve this, we formulate the detection problem from the anchor point's perspective and identify ineffective training as the main problem. Our key insight is that anchor points should be optimized jointly as a group both within and across feature pyramid levels. We propose a simple yet effective training strategy with soft-weighted anchor points and soft-selected pyramid levels to address the false attention issue within each pyramid level and the feature selection issue across all the pyramid levels, respectively. To evaluate the effectiveness, we train a single-stage anchor-free detector called Soft Anchor-Point Detector (SAPD). Experiments show that our concise SAPD pushes the envelope of speed/accuracy trade-off to a new level, outperforming recent state-of-the-art anchor-free and anchor-based detectors. Without bells and whistles, our best model can achieve a single-model single-scale AP of 47.4% on COCO.

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xuannianz/FSAF mentioned on GitHubtf report
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filter_detections xuannianz/SAPD/layers.py community (archive-listed) unverified Apache-2.0 (permissive) · a782c8c256181c85 · report
focal xuannianz/SAPD/losses.py community (archive-listed) unverified Apache-2.0 (permissive) · 9caad353ee153b05 · report
focal_with_weight_and_mask xuannianz/SAPD/losses.py community (archive-listed) unverified Apache-2.0 (permissive) · 7cc7e8bd2b8ad8ef · report
round_filters xuannianz/SAPD/efficientnet.py community (archive-listed) unverified Apache-2.0 (permissive) · 00c946065068bd77 · report
round_repeats xuannianz/SAPD/efficientnet.py community (archive-listed) unverified Apache-2.0 (permissive) · 6cc796a8212b5586 · report
smooth_l1 xuannianz/SAPD/losses.py community (archive-listed) unverified Apache-2.0 (permissive) · eb88cc992d53c796 · report

Tasks

Dense Object DetectionObjectObject Detectionfeature selectionobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Dense Object Detection SKU-110K SAPD AP 55.7 #3 of 5 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) AP50 67.4 #117 of 225 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) AP75 51.1 #117 of 225 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) APL 61.5 #117 of 225 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) APM 50.3 #117 of 225 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) APS 28.1 #117 of 225 Archive leaderboard report
Object Detection COCO test-dev SAPD (ResNeXt-101, single-scale) box mAP 47.4 #117 of 225 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.

Methods

Feature SelectionSPEED

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