Papers › InstantSplat: Sparse-view SfM-free Gaussian Splatting in Seconds

InstantSplat: Sparse-view SfM-free Gaussian Splatting in Seconds

29 Mar 2024arXiv:2403.20309archive 2025-07-28

Zhiwen Fan, Kairun Wen, Wenyan Cong, Kevin Wang, Jian Zhang, Xinghao Ding, Danfei Xu, Boris Ivanovic, Marco Pavone, Georgios Pavlakos, Zhangyang Wang, Yue Wang

While neural 3D reconstruction has advanced substantially, it typically requires densely captured multi-view data with carefully initialized poses (e.g., using COLMAP). However, this requirement limits its broader applicability, as Structure-from-Motion (SfM) is often unreliable in sparse-view scenarios where feature matches are limited, resulting in cumulative errors. In this paper, we introduce InstantSplat, a novel and lightning-fast neural reconstruction system that builds accurate 3D representations from as few as 2-3 images. InstantSplat adopts a self-supervised framework that bridges the gap between 2D images and 3D representations using Gaussian Bundle Adjustment (GauBA) and can be optimized in an end-to-end manner. InstantSplat integrates dense stereo priors and co-visibility relationships between frames to initialize pixel-aligned geometry by progressively expanding the scene avoiding redundancy. Gaussian Bundle Adjustment is used to adapt both the scene representation and camera parameters quickly by minimizing gradient-based photometric error. Overall, InstantSplat achieves large-scale 3D reconstruction in mere seconds by reducing the required number of input views. It achieves an acceleration of over 20 times in reconstruction, improves visual quality (SSIM) from 0.3755 to 0.7624 than COLMAP with 3D-GS, and is compatible with multiple 3D representations (3D-GS, 2D-GS, and Mip-Splatting).

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apply_log_to_norm NVlabs/InstantSplat/mast3r/losses.py official repository ran fingerprinted no licence file found · pointer only · f3fd659d5f95c771 · report
get_similarities NVlabs/InstantSplat/mast3r/losses.py official repository ran no licence file found · pointer only · 6e6b3f8c6d2c3d69 · report
l1_loss NVlabs/InstantSplat/utils/loss_utils.py official repository ran fingerprinted no licence file found · pointer only · ac0e42d6fbcfbbe6 · report
l1_loss_mask NVlabs/InstantSplat/utils/loss_utils.py official repository ran fingerprinted licence not identified · pointer only · 5f5276237914e4c7 · report
ssim_loss_mask NVlabs/InstantSplat/utils/loss_utils.py official repository ran licence not identified · pointer only · a6db8d31ea8e2b6f · report
load_model NVlabs/InstantSplat/dust3r/model.py official repository unverified no licence file found · pointer only · 1e3f140b86bb9a08 · report

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3D ReconstructionNovel View SynthesisSSIM

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