Papers › Weakly Supervised Action Selection Learning in Video
Weakly Supervised Action Selection Learning in Video
Junwei Ma, Satya Krishna Gorti, Maksims Volkovs, Guangwei Yu
Localizing actions in video is a core task in computer vision. The weakly supervised temporal localization problem investigates whether this task can be adequately solved with only video-level labels, significantly reducing the amount of expensive and error-prone annotation that is required. A common approach is to train a frame-level classifier where frames with the highest class probability are selected to make a video-level prediction. Frame level activations are then used for localization. However, the absence of frame-level annotations cause the classifier to impart class bias on every frame. To address this, we propose the Action Selection Learning (ASL) approach to capture the general concept of action, a property we refer to as "actionness". Under ASL, the model is trained with a novel class-agnostic task to predict which frames will be selected by the classifier. Empirically, we show that ASL outperforms leading baselines on two popular benchmarks THUMOS-14 and ActivityNet-1.2, with 10.3% and 5.7% relative improvement respectively. We further analyze the properties of ASL and demonstrate the importance of actionness. Full code for this work is available here: https://github.com/layer6ai-labs/ASL.
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Tasks
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Weakly Supervised Action Localization | ActivityNet-1.2 | ASL | Mean mAP | 25.8 | #10 of 19 | Archive leaderboard | report |
| Weakly Supervised Action Localization | ActivityNet-1.2 | ASL | mAP@0.5 | 40.2 | #10 of 19 | Archive leaderboard | report |
| Weakly Supervised Action Localization | FineAction | ASL | mAP | 3.30 | #4 of 4 | Archive leaderboard | report |
| Weakly Supervised Action Localization | FineAction | ASL | mAP IOU@0.5 | 2.68 | #4 of 4 | Archive leaderboard | report |
| Weakly Supervised Action Localization | FineAction | ASL | mAP IOU@0.75 | 0.81 | #4 of 4 | Archive leaderboard | report |
| Weakly Supervised Action Localization | FineAction | ASL | mAP IOU@0.95 | 3.30 | #4 of 4 | 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.
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