DarkVGGT: Seeing Through Darkness Using Thermal Geometry

Recent feed-forward 3D reconstruction methods have demonstrated strong performance and flexibility in efficient end-to-end scene geometry estimation from image streams. However, their reliance on visible-light appearance makes them vulnerable in dark and low-visibility environments, where RGB cues are severely degraded and geometric evidence becomes ambiguous. To address this challenge, we propose DarkVGGT, a structured RGB-T adaptation of pretrained VGGT for robust 3D estimation in low-light scenes. DarkVGGT introduces two complementary modules. First, complementary thermal feature factorization processes thermal tokens through content-preserving and high-frequency residual pathways controlled by learned complementary allocation weights. Second, geometry-shared thermal routing aligns RGB and thermal representations in a shared latent space and selectively injects a gated feature correction into the RGB stream. Together, these components enable accurate thermal-informed geometry estimation under degraded RGB conditions while largely preserving performance in well-lit environments. Experiments on low-visibility RGB-T benchmarks demonstrate consistent improvements in both depth and camera pose estimation over existing feed-forward geometry baselines.