L4GM: Large 4D Gaussian Reconstruction Model

Jiawei Ren; Kevin Xie; Ashkan Mirzaei; Hanxue Liang; Xiaohui Zeng; Karsten Kreis; Ziwei Liu; Antonio Torralba; Sanja Fidler; Seung Wook Kim; Huan Ling

arXiv · 2406.10324

L4GM: Large 4D Gaussian Reconstruction Model

Jiawei Ren·Kevin Xie·Ashkan Mirzaei·Hanxue Liang·Xiaohui Zeng·Karsten Kreis·Ziwei Liu·Antonio Torralba·Sanja Fidler·Seung Wook Kim·Huan Ling

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Abstract

We present L4GM, the first 4D Large Reconstruction Model that produces animated objects from a single-view video input -- in a single feed-forward pass that takes only a second. Key to our success is a novel dataset of multiview videos containing curated, rendered animated objects from Objaverse. This dataset depicts 44K diverse objects with 110K animations rendered in 48 viewpoints, resulting in 12M videos with a total of 300M frames. We keep our L4GM simple for scalability and build directly on top of LGM, a pretrained 3D Large Reconstruction Model that outputs 3D Gaussian ellipsoids from multiview image input. L4GM outputs a per-frame 3D Gaussian Splatting representation from video frames sampled at a low fps and then upsamples the representation to a higher fps to achieve temporal smoothness. We add temporal self-attention layers to the base LGM to help it learn consistency across time, and utilize a per-timestep multiview rendering loss to train the model. The representation is upsampled to a higher framerate by training an interpolation model which produces intermediate 3D Gaussian representations. We showcase that L4GM that is only trained on synthetic data generalizes extremely well on in-the-wild videos, producing high quality animated 3D assets.

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BibTeX RIS

Jiawei Ren, Kevin Xie, Ashkan Mirzaei, Hanxue Liang, Xiaohui Zeng, Karsten Kreis, Ziwei Liu, Antonio Torralba, Sanja Fidler, Seung Wook Kim, Huan Ling. 2024-06-14. L4GM: Large 4D Gaussian Reconstruction Model. https://arxiv.org/abs/2406.10324

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