This content will become publicly available on December 2, 2026

Title: Novel View Synthesis from A Few Glimpses via Test-Time Natural Video Completion
Given just a few glimpses of a scene, can you imagine the movie playing out as the camera glides through it? That's the lens we take on \emph{sparse-input novel view synthesis}, not only as filling spatial gaps between widely spaced views, but also as \emph{completing a natural video} unfolding through space. We recast the task as \emph{test-time natural video completion}, using powerful priors from \emph{pretrained video diffusion models} to hallucinate plausible in-between views. Our \emph{zero-shot, generation-guided} framework produces pseudo views at novel camera poses, modulated by an \emph{uncertainty-aware mechanism} for spatial coherence. These synthesized frames densify supervision for \emph{3D Gaussian Splatting} (3D-GS) for scene reconstruction, especially in under-observed regions. An iterative feedback loop lets 3D geometry and 2D view synthesis inform each other, improving both the scene reconstruction and the generated views. The result is coherent, high-fidelity renderings from sparse inputs \emph{without any scene-specific training or fine-tuning}. On LLFF, DTU, DL3DV, and MipNeRF-360, our method significantly outperforms strong 3D-GS baselines under extreme sparsity. Our project page is at \url{https://decayale.github.io/project/SV2CGS}.  more » « less
Award ID(s):
2313151 2215542
PAR ID:
10677868
Author(s) / Creator(s):
; ;
Publisher / Repository:
Neural Information Processing Systems
Date Published:
Subject(s) / Keyword(s):
novel view synthesis, test-time optimization
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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