VAU-R1: Advancing Video Anomaly Understanding via Reinforcement
  Fine-Tuning
Video Anomaly Understanding (VAU) is essential for applications such as smart
cities, security surveillance, and disaster alert systems, yet remains
challenging due to its demand for fine-grained spatio-temporal perception and
robust reasoning under ambiguity. Despite advances in anomaly detection,
existing methods often lack interpretability and struggle to capture the causal
and contextual aspects of abnormal events. This limitation is further
compounded by the absence of comprehensive benchmarks for evaluating reasoning
ability in anomaly scenarios. To address both challenges, we introduce VAU-R1,
a data-efficient framework built upon Multimodal Large Language Models (MLLMs),
which enhances anomaly reasoning through Reinforcement Fine-Tuning (RFT).
Besides, we propose VAU-Bench, the first Chain-of-Thought benchmark tailored
for video anomaly reasoning, featuring multiple-choice QA, detailed rationales,
temporal annotations, and descriptive captions. Empirical results show that
VAU-R1 significantly improves question answering accuracy, temporal grounding,
and reasoning coherence across diverse contexts. Together, our method and
benchmark establish a strong foundation for interpretable and reasoning-aware
video anomaly understanding. Our code is available at
https://github.com/GVCLab/VAU-R1.
683e501c89dc42ba0515a4d8
Liyun Zhu
683e501c89dc42ba0515a4d9
Qixiang Chen
683e501c89dc42ba0515a4da
Xi Shen
683e501c89dc42ba0515a4db
Xiaodong Cun
claimed_verified
2025-06-30T06:23:30.700Z
63184c517ca1b876d99b7e0e
https://cdn-avatars.huggingface.co/v1/production/uploads/63184c517ca1b876d99b7e0e/b-qDExoeJuDXK0cJBZKnz.jpeg
Xiaodong Cun
user
vinthony
VAU-R1: Advancing Video Anomaly Understanding via Reinforcement
  Fine-Tuning
Video Anomaly Understanding (VAU) is essential for applications such as smart
cities, security surveillance, and disaster alert systems, yet remains
challenging due to its demand for fine-grained spatio-temporal perception and
robust reasoning under ambiguity. Despite advances in anomaly detection,
existing methods often lack interpretability and struggle to capture the causal
and contextual aspects of abnormal events. This limitation is further
compounded by the absence of comprehensive benchmarks for evaluating reasoning
ability in anomaly scenarios. To address both challenges, we introduce VAU-R1,
a data-efficient framework built upon Multimodal Large Language Models (MLLMs),
which enhances anomaly reasoning through Reinforcement Fine-Tuning (RFT).
Besides, we propose VAU-Bench, the first Chain-of-Thought benchmark tailored
for video anomaly reasoning, featuring multiple-choice QA, detailed rationales,
temporal annotations, and descriptive captions. Empirical results show that
VAU-R1 significantly improves question answering accuracy, temporal grounding,
and reasoning coherence across diverse contexts. Together, our method and
benchmark establish a strong foundation for interpretable and reasoning-aware
video anomaly understanding. Our code is available at
https://github.com/GVCLab/VAU-R1.
VAU-R1 uses Multimodal Large Language Models with Reinforcement Fine-Tuning to enhance video anomaly reasoning, complemented by VAU-Bench, a Chain-of-Thought benchmark for evaluating anomaly understanding.
Multimodal Large Language Models (MLLMs) Reinforcement Fine-Tuning (RFT) Chain-of-Thought benchmark question answering temporal grounding reasoning coherence