UnLoc: A Unified Framework for Video Localization Tasks
This addresses the challenge of video understanding for researchers and practitioners by providing a versatile, high-performing model that simplifies multi-task localization.
The paper tackles the problem of temporal localization in untrimmed videos by introducing UnLoc, a unified framework that achieves state-of-the-art results on moment retrieval, temporal localization, and action segmentation tasks without needing action proposals or motion-based features.
While large-scale image-text pretrained models such as CLIP have been used for multiple video-level tasks on trimmed videos, their use for temporal localization in untrimmed videos is still a relatively unexplored task. We design a new approach for this called UnLoc, which uses pretrained image and text towers, and feeds tokens to a video-text fusion model. The output of the fusion module are then used to construct a feature pyramid in which each level connects to a head to predict a per-frame relevancy score and start/end time displacements. Unlike previous works, our architecture enables Moment Retrieval, Temporal Localization, and Action Segmentation with a single stage model, without the need for action proposals, motion based pretrained features or representation masking. Unlike specialized models, we achieve state of the art results on all three different localization tasks with a unified approach. Code will be available at: \url{https://github.com/google-research/scenic}.