PromptTAD: Object-Prompt Enhanced Traffic Anomaly Detection

Ego-centric Traffic Anomaly Detection (TAD) aims to identify abnormal events in videos captured by dashboard-mounted cameras in vehicles. Compared to anomaly detection in roadside surveillance videos, ego-centric TAD poses greater challenges due to the dynamic backgrounds caused by vehicle motion. Previous frame-level methods are often vulnerable to interference from these dynamic backgrounds and struggle to detect small objects located at a distance or off-center. To address these challenges, we propose an object-prompt enhanced method that integrates detected traffic objects into a frame-level TAD framework. Our approach introduces an object-prompt scheme comprising an object prompt encoder, along with two cross-attention-based aggregation modules: an instance-wise aggregation module for fusing information between object instances and the scene, and a relation-wise aggregation module for capturing relationships inter-objects. Additionally, we design an instance-level loss to supervise anomaly detection at the object level. Our method effectively mitigates interference from dynamic backgrounds, improves the detection of distant or off-center anomalies, and enables precise spatial localization of anomalies. Experimental results on the DoTA and DADA-2000 datasets demonstrate that our method achieves state-of-the-art performance.