Efficiently Reconstructing Dynamic Scenes One D4RT at a Time

October 14, 2026

-a unified transformer jointly infers depth, spatiotemporal correspondence, and full camera parameters from a single video
-enables 4D reconstruction
-state-of-the-art 3D reconstruction methods such as VGGT cannot establish correspondence for dynamic portions of a scene
-a global self-attention encoder first transforms the input video into a global scene-representation latent
-the decoder can be independently queried for the 3D position of any given 2D point from ttextsourcet_{\\text{source}} at ttexttargett_{\\text{target}} in camera coordinate ttextcamt_{\\text{cam}}

3D Models vs. 4D Models

-3D models: better spatial understanding, trained on image datasets
-does spatial understanding over time lead to good 4D/video understanding?
-4D models: better temporal understanding, trained on video datasets
-open question: can 4D models become as strong at spatial understanding as 3D models?