Papers › Learning Prompt-Enhanced Context Features for Weakly-Supervised Video Anomaly Detection

Learning Prompt-Enhanced Context Features for Weakly-Supervised Video Anomaly Detection

26 Jun 2023arXiv:2306.14451archive 2025-07-28

Yujiang Pu, Xiaoyu Wu, Lulu Yang, Shengjin Wang

Video anomaly detection under weak supervision presents significant challenges, particularly due to the lack of frame-level annotations during training. While prior research has utilized graph convolution networks and self-attention mechanisms alongside multiple instance learning (MIL)-based classification loss to model temporal relations and learn discriminative features, these methods often employ multi-branch architectures to capture local and global dependencies separately, resulting in increased parameters and computational costs. Moreover, the coarse-grained interclass separability provided by the binary constraint of MIL-based loss neglects the fine-grained discriminability within anomalous classes. In response, this paper introduces a weakly supervised anomaly detection framework that focuses on efficient context modeling and enhanced semantic discriminability. We present a Temporal Context Aggregation (TCA) module that captures comprehensive contextual information by reusing the similarity matrix and implementing adaptive fusion. Additionally, we propose a Prompt-Enhanced Learning (PEL) module that integrates semantic priors using knowledge-based prompts to boost the discriminative capacity of context features while ensuring separability between anomaly sub-classes. Extensive experiments validate the effectiveness of our method's components, demonstrating competitive performance with reduced parameters and computational effort on three challenging benchmarks: UCF-Crime, XD-Violence, and ShanghaiTech datasets. Notably, our approach significantly improves the detection accuracy of certain anomaly sub-classes, underscoring its practical value and efficacy. Our code is available at: https://github.com/yujiangpu20/PEL4VAD.

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CLAS2 yujiangpu20/pel4vad/loss.py official repository unverified MIT (permissive) · 6d53914a9cfb0d0e · report
KLV_loss yujiangpu20/pel4vad/loss.py official repository unverified MIT (permissive) · d19cc370f004029b · report
build_config yujiangpu20/pel4vad/configs.py official repository unverified MIT (permissive) · 3da167d2f6c1fe65 · report
build_model yujiangpu20/pel4vad/prompt_extract/clip/model.py official repository unverified MIT (permissive) · 39e6b23b55f376ea · report
get_logger yujiangpu20/pel4vad/log.py official repository unverified MIT (permissive) · e54688f4d92cf4e6 · report
pad yujiangpu20/pel4vad/utils.py official repository unverified MIT (permissive) · 6243210611bed58e · report
random_extract yujiangpu20/pel4vad/utils.py official repository unverified MIT (permissive) · 88651357a6ab3451 · report
temporal_smooth yujiangpu20/pel4vad/loss.py official repository unverified MIT (permissive) · 5d4cc204c0da711e · report
uniform_extract yujiangpu20/pel4vad/utils.py official repository unverified MIT (permissive) · 4b4b91623e8eb765 · report

Tasks

Anomaly DetectionAnomaly Detection In Surveillance VideosVideo Anomaly DetectionWeakly-supervised Anomaly DetectionWeakly-supervised Video Anomaly Detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Anomaly Detection In Surveillance Videos ShanghaiTech Weakly Supervised PEL AUC-ROC 98.14 #1 of 12 Archive leaderboard report
Anomaly Detection In Surveillance Videos UCF-Crime PEL ROC AUC 86.76 #8 of 21 Archive leaderboard report
Anomaly Detection In Surveillance Videos XD-Violence PEL AP 85.59 #5 of 17 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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