3D-Aware Vision-Language Models Fine-Tuning with Geometric Distillation
Journal:
arXiv
Published Date:
Jun 11, 2025
Abstract
Vision-Language Models (VLMs) have shown remarkable performance on diverse
visual and linguistic tasks, yet they remain fundamentally limited in their
understanding of 3D spatial structures. We propose Geometric Distillation, a
lightweight, annotation-free fine-tuning framework that injects human-inspired
geometric cues into pretrained VLMs without modifying their architecture. By
distilling (1) sparse correspondences, (2) relative depth relations, and (3)
dense cost volumes from off-the-shelf 3D foundation models (e.g., MASt3R,
VGGT), our method shapes representations to be geometry-aware while remaining
compatible with natural image-text inputs. Through extensive evaluations on 3D
vision-language reasoning and 3D perception benchmarks, our method consistently
outperforms prior approaches, achieving improved 3D spatial reasoning with
significantly lower computational cost. Our work demonstrates a scalable and
efficient path to bridge 2D-trained VLMs with 3D understanding, opening up
wider use in spatially grounded multimodal tasks.