Beyond Spatio-Temporal Priors: A Generalizable Approach for Dense Correspondence Matching
Organizations: The University of Hong Kong · ByteDance Seed · Zhejiang University
Abstract
Dense correspondence matching has historically been bounded by simplifying spatio-temporal priors, such as smooth motion and rigid geometry. While effective for classical tasks, these assumptions break down in image editing and reference-guided generation (IEG), where transformations can preserve visual identity while breaking physical continuity. To establish identity-preserving correspondence across such transformations, we introduce FreeMatching, a generalizable framework combining generative and semantic foundation representations with heterogeneous supervision from classical datasets, tracked videos, and synthetic scenes. Teacher-guided iterative refinement further improves correspondence in IEG without dense correspondence annotations. Experimentally, a single FreeMatching model substantially improves correspondence quality on challenging IEG image pairs while retaining competitive performance on classical benchmarks. Furthermore, we demonstrate its utility as a quantitative metric for evaluating identity preservation, with scores that correlate with human judgment. The code is available at https://github.com/luping-liu/FreeMatching.
Figures & tables
| Dataset | Ratio | Dataset | Ratio |
|---|---|---|---|
| ScanNet++ [ 33 ] | 15% | Spring [ 34 ] | 5% |
| BlendedMVS [ 35 ] | 10% | PointOdyssey [ 36 ] | 5% |
| FlyingThings [ 18 ] | 10% | FlyingChairs [ 37 ] | 5% |
| DynamicReplica [ 38 ] | 10% | ||
| Video (Ours) | 20% | Blender (Ours) | 20% |
| Sintel (Clean) | Sintel (Final) | KITTI-2015 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Method | EPE | 1px | 2px | 5px | EPE | 1px | 2px | 5px | EPE | 1px | 2px | 5px |
| GMFlow [ 21 ] | 1.21 | 41.3 | 12.6 | 1.9 | 1.56 | 42.7 | 14.4 | 3.2 | 4.32 | 60.3 | 35.5 | 16.1 |
| SEA-RAFT [ 32 ] | 0.43 | 5.9 | 2.7 | 0.9 | 0.81 | 8.7 | 4.8 | 2.1 | 1.97 | 29.7 | 16.8 | 7.2 |
| UniMatch [ 6 ] | 0.40 | 5.4 | 2.4 | 0.8 | 0.75 | 8.9 | 4.9 | 2.2 | 1.52 | 24.1 | 12.5 | 5.1 |
| RoMa [ 5 ] | 1.24 | 25.2 | 8.1 | 4.5 | 2.49 | 35.6 | 16.6 | 8.7 | 5.91 | 41.4 | 27.5 | 18.4 |
| UFM [ 7 ] | 0.92 | 14.2 | 6.4 | 2.1 | 1.48 | 16.9 | 9.0 | 3.8 | 4.75 | 39.6 | 24.5 | 15.5 |
| Model | Ref-MSE | LPIPS | SigLIP 2 | DINOv3 |
|---|---|---|---|---|
| Identity | 23.65 | 81.97 | 86.67 | 52.38 |
| SEA-RAFT [ 32 ] | 18.49 | 72.45 | 85.18 | 58.14 |
| UniMatch [ 6 ] | 11.07 | 58.42 | 87.86 | 66.35 |
| RoMa [ 5 ] | 8.08 | 48.91 | 87.73 | 70.15 |
| UFM [ 7 ] | 10.41 | 53.05 | 86.97 | 66.77 |
| FreeMatching (Ours) | 6.22 | 45.41 | 90.77 | 80.01 |
| Method | Ref-MSE | Full-MSE | Ref-DINOv2 | OpenCLIP |
|---|---|---|---|---|
| FreeMatching (10k-IEG) | 6.22 | 10.99 | 54.31 | 70.56 |
| UFM (10k-IEG) [ 7 ] | 8.55 | 13.48 | 39.65 | 56.48 |
| RoMa (10k-IEG) [ 5 ] | 9.70 | 16.57 | 47.14 | 61.18 |
| ID | FLUX Init | DINOv3 | Video & Blender | Refine | DINOv3 |
|---|---|---|---|---|---|
| 1 | 67.31 | ||||
| 2 | ✓ | 69.28 | |||
| 3 | ✓ | ✓ | 72.76 | ||
| 4 | ✓ | ✓ | ✓ | 76.52 | |
| 5 | ✓ | ✓ | ✓ | ✓ | 80.01 |
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
| Method | Training cost (H20 GPU-hours) |
|---|---|
| FreeMatching | 42.0 |
| UFM [ 7 ] | 16.8 |
| RoMa [ 5 ] | 30.8 |
| Method | Latency (ms/pair) | Peak memory (GiB) |
|---|---|---|
| FreeMatching | 121.9 | 15.18 |
| UFM [ 7 ] | 51.3 | 2.35 |
| RoMa [ 5 ] | 102.5 | 2.58 |
| Method | Sintel Clean | Sintel Final | KITTI | ScanNet | ETH3D |
|---|---|---|---|---|---|
| FreeMatching (10k-IEG) | 1.05 | 1.36 | 4.95 | 8.56 | 10.23 |
| UFM (10k-IEG) [ 7 ] | 0.92 | 1.48 | 4.75 | 12.03 | 12.98 |
| RoMa (10k-IEG) [ 5 ] | 1.24 | 2.49 | 5.91 | 12.03 | 11.26 |
| Checkpoint | Ref-MSE | Sintel Clean | Sintel Final | KITTI | ScanNet | ETH3D |
|---|---|---|---|---|---|---|
| FreeMatching-S1 | 8.08 | 1.11 | 1.73 | 6.26 | 8.85 | 11.68 |
| FreeMatching (10k-Flow) | 7.26 | 0.98 | 1.59 | 6.46 | 8.91 | 11.64 |
| FreeMatching (10k-IEG) | 6.22 | 1.05 | 1.36 | 4.95 | 8.56 | 10.23 |
| Model | Human | LPIPS | DINOv3 |
|---|---|---|---|
| SEA-RAFT [ 32 ] | 0.49 | 72.45 | 58.14 |
| RoMa [ 5 ] | 1.39 | 48.91 | 70.15 |
| UFM [ 7 ] | 1.13 | 53.05 | 66.77 |
| FreeMatching (Ours) | 2.25 | 45.41 | 80.01 |