  Video-grounded dialogue understanding is a challenging problem that requires
machine to perceive, parse and reason over situated semantics extracted from
weakly aligned video and dialogues. Most existing benchmarks treat both
modalities the same as a frame-independent visual understanding task, while
neglecting the intrinsic attributes in multimodal dialogues, such as scene and
topic transitions. In this paper, we present Video-grounded Scene&Topic AwaRe
dialogue (VSTAR) dataset, a large scale video-grounded dialogue understanding
dataset based on 395 TV series. Based on VSTAR, we propose two benchmarks for
video-grounded dialogue understanding: scene segmentation and topic
segmentation, and one benchmark for video-grounded dialogue generation.
Comprehensive experiments are performed on these benchmarks to demonstrate the
importance of multimodal information and segments in video-grounded dialogue
understanding and generation.
