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EVOQUER: Enhancing Temporal Grounding with Video-Pivoted BackQuery Generation

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 نشر من قبل Yanjun Gao
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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Temporal grounding aims to predict a time interval of a video clip corresponding to a natural language query input. In this work, we present EVOQUER, a temporal grounding framework incorporating an existing text-to-video grounding model and a video-assisted query generation network. Given a query and an untrimmed video, the temporal grounding model predicts the target interval, and the predicted video clip is fed into a video translation task by generating a simplified version of the input query. EVOQUER forms closed-loop learning by incorporating loss functions from both temporal grounding and query generation serving as feedback. Our experiments on two widely used datasets, Charades-STA and ActivityNet, show that EVOQUER achieves promising improvements by 1.05 and 1.31 at [email protected]. We also discuss how the query generation task could facilitate error analysis by explaining temporal grounding model behavior.



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