Decoupling Static and Hierarchical Motion Perception for Referring Video Segmentation
Shuting He, Henghui Ding
TL;DR
This work tackles the challenge of referring video segmentation by decoupling static grounding from motion reasoning. It introduces an expression-decoupling module to separate static cues $F_s$ from motion cues $F_m$, and a Hierarchical Motion Perception (HMP) module to capture multi-scale temporal information via object-token trajectories and progressive merging. An object-wise contrastive learning framework with a memory bank enhances discrimination among visually similar motions, further boosting temporal understanding. The approach achieves state-of-the-art results across five datasets, with a notable $9.2\%$ improvement in $J\&F$ on MeViS, demonstrating strong gains in motion-aware video-language grounding and generalization to diverse benchmarks.
Abstract
Referring video segmentation relies on natural language expressions to identify and segment objects, often emphasizing motion clues. Previous works treat a sentence as a whole and directly perform identification at the video-level, mixing up static image-level cues with temporal motion cues. However, image-level features cannot well comprehend motion cues in sentences, and static cues are not crucial for temporal perception. In fact, static cues can sometimes interfere with temporal perception by overshadowing motion cues. In this work, we propose to decouple video-level referring expression understanding into static and motion perception, with a specific emphasis on enhancing temporal comprehension. Firstly, we introduce an expression-decoupling module to make static cues and motion cues perform their distinct role, alleviating the issue of sentence embeddings overlooking motion cues. Secondly, we propose a hierarchical motion perception module to capture temporal information effectively across varying timescales. Furthermore, we employ contrastive learning to distinguish the motions of visually similar objects. These contributions yield state-of-the-art performance across five datasets, including a remarkable $\textbf{9.2%}$ $\mathcal{J\&F}$ improvement on the challenging $\textbf{MeViS}$ dataset. Code is available at https://github.com/heshuting555/DsHmp.
