OVO-Bench: How Far is Your Video-LLMs from Real-World Online Video
  Understanding?
Authors: name: Yifei Li, name: Junbo Niu, name: Ziyang Miao, name: Chunjiang Ge, name: Yuanhang Zhou, name: Qihao He, name: Xiaoyi Dong, name: Haodong Duan, name: Shuangrui Ding, name: Rui Qian, name: Pan Zhang, name: Yuhang Zang, name: Yuhang Cao, name: Conghui He, name: Jiaqi Wang

Temporal Awareness, the ability to reason dynamically based on the timestamp
when a question is raised, is the key distinction between offline and online
video LLMs. Unlike offline models, which rely on complete videos for static,
post hoc analysis, online models process video streams incrementally and
dynamically adapt their responses based on the timestamp at which the question
is posed. Despite its significance, temporal awareness has not been adequately
evaluated in existing benchmarks. To fill this gap, we present OVO-Bench
(Online-VideO-Benchmark), a novel video benchmark that emphasizes the
importance of timestamps for advanced online video understanding capability
benchmarking. OVO-Bench evaluates the ability of video LLMs to reason and
respond to events occurring at specific timestamps under three distinct
scenarios: (1) Backward tracing: trace back to past events to answer the
question. (2) Real-time understanding: understand and respond to events as they
unfold at the current timestamp. (3) Forward active responding: delay the
response until sufficient future information becomes available to answer the
question accurately. OVO-Bench comprises 12 tasks, featuring 644 unique videos
and approximately human-curated 2,800 fine-grained meta-annotations with
precise timestamps. We combine automated generation pipelines with human
curation. With these high-quality samples, we further developed an evaluation
pipeline to systematically query video LLMs along the video timeline.
Evaluations of nine Video-LLMs reveal that, despite advancements on traditional
benchmarks, current models struggle with online video understanding, showing a
significant gap compared to human agents. We hope OVO-Bench will drive progress
in video LLMs and inspire future research in online video reasoning. Our
benchmark and code can be accessed at https://github.com/JoeLeelyf/OVO-Bench.