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arXiv:2512.19949cs.CV

How Much 3D Do Video Foundation Models Encode?

Zixuan Huang, Xiang Li, Zhaoyang Lv, James M. Rehg

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Abstract

Videos are continuous 2D projections of 3D worlds. After training on large video data, will global 3D understanding naturally emerge? We study this by quantifying the 3D understanding of existing Video Foundation Models (VidFMs) pretrained on vast video data. We propose the first model-agnostic framework that measures the 3D awareness of various VidFMs by estimating multiple 3D properties from their features via shallow read-outs. Our study presents meaningful findings regarding the 3D awareness of VidFMs on multiple axes. In particular, we show that state-of-the-art video generation models exhibit a strong understanding of 3D objects and scenes, despite not being trained on any 3D data. Such understanding can even surpass that of large expert models specifically trained for 3D tasks. Our findings, together with the 3D benchmarking of major VidFMs, provide valuable observations for building scalable 3D models.

arXiv comments
Project Page: https://vidfm-3d-probe.github.io
Journal reference
DOI
Subjects
cs.CVComputer Vision and Pattern Recognition cs.AIArtificial Intelligence

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  1. The dawn of a world simulator 1 comment
    • Here's a recent paper showing that models trained to generate videos develop strong geometric representations and understanding: https://arxiv.org/abs/2512.19949

      in-silicoView on HNParent context

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