Overview
Field: Computer Vision Authors: Ruihang Zhang, Felix Taubner, Pooja Ravi Published: 2025-07-09 arXiv: 2507.06829
Abstract
Tracking the six-degree-of-freedom (6-DoF) pose of objects and surfaces from monocular video is a long-standing problem in computer vision. To tackle this problem, existing methods require inputs beyond the video itself — such as 3D models, depth maps, object masks, or task-specific learned features — and they struggle with textureless, transparent, reflective, or deformable surfaces.
ProxyPose recasts 6-DoF pose tracking as video-to-video translation. Given only a video and a single marked pixel in the first frame, a fine-tuned video diffusion model translates the input into a proxy video — a synthetic video depicting a colored polyhedron undergoing the same local rigid-body motion as the surface region at the marked pixel. Because the proxy's geometry and appearance are known by construction, recovering its full 6-DoF trajectory reduces to classic pose estimation with an off-the-shelf solver.
Key Points
- Problem reformulation: 6-DoF pose tracking is treated as a video-to-video translation task rather than direct pose regression or correspondence matching.
- Diffusion-based translation: A fine-tuned video diffusion model converts the input video into a proxy video of a known colored polyhedron mimicking the local surface motion at the marked pixel.
- Classic estimation on top: With the proxy's geometry and appearance known by construction, full 6-DoF trajectory recovery uses standard off-the-shelf pose estimation solvers.
- Leverages video pretraining: Large-scale video pretraining absorbs the hardest aspects of pose tracking — challenging materials, occlusion, and deformation — into the translation step.
- Minimal assumptions: Operates at the pixel level without assumptions about object identity, boundaries, or global rigidity.
- No extra inputs needed: Achieves state-of-the-art 6-DoF tracking accuracy without 3D models, depth maps, or masks, and the video model is fine-tuned only on synthetic data.
- Extensibility: Scales to face tracking, camera pose estimation, and challenging in-the-wild scenes that existing methods cannot handle.
- Paper: https://arxiv.org/abs/2507.06829