/BN-WVAD

The official implementation of "Divergence of Features and Mean: A BatchNorm-based Abnormality Criterion for Weakly Supervised Video Anomaly Detection"

Primary LanguagePython

BN-WVAD

The official implementation of "BatchNorm-based Weakly Supervised Video Anomaly Detection".

Abstract

In weakly supervised video anomaly detection (WVAD),where only video-level labels are provided denoting thepresence or absence of abnormal events, the primary challenge arises from the inherent ambiguity in temporal annotations of abnormal occurrences. Inspired by the statistical insight that temporal features of abnormal events often exhibit outlier characteristics, we introduce the incorporation of BatchNorm into WVAD, resulting in a novel method termed BN-WVAD. Specifically, we treat the Divergence of Feature from Mean vector of BatchNorm as a reliable abnormality criterion to screen potential abnormal snippets. Moreover, a batch-level selection strategy is devised to filter more potential abnormal snippets in the video with more abnormal events occurring. In particular, the proposed DFM criterion is also discriminative for anomaly recognition and more resilient to label noise. Integrated with the prediction of the anomaly classifier, our DFM contributes to the discrimination of abnormal events, thereby enhancing the tolerance to inevitable misselection.

framework

Enviroment

  • Python 3.8.16
  • PyTorch 2.0.0
  • Torchvision 0.15.2
  • cudatoolkit 11.7

Dataset

We use the extracted I3D features for UCF-Crime and XD-Violence datasets from the following works:

UCF-Crime 10-crop I3D features

XD-Violence 5-crop I3D features

Train

python main.py --version train --root_dir data_root

Inference

python infer.py --model_path ./ckpts/xd_best_2022.pkl --root_dir data_root

Result on XD-Violence

Method AUC AUC_sub AP AP_sub
UR-DMU 94.02 81.66 82.36 82.85
BN-WVAD 94.71 83.59 84.93 85.45

Thanks to