You Only Pose Once: A Minimalist's Detection Transformer for Monocular RGB Category-level 9D Multi-Object Pose Estimation
Hakjin Lee, Junghoon Seo, Jaehoon Sim
TL;DR
This work tackles monocular RGB, category-level $9$-DoF pose estimation by proposing YOPO, a single-stage, end-to-end RGB-only transformer detector that unifies object detection with 3D pose reasoning. YOPO directly predicts $(c, oldsymbol{R}, oldsymbol{t}, oldsymbol{s})$ in one forward pass, using a bounding-box–conditioned 3D module and a 6D-aware bipartite matching objective, trained solely from RGB images with pose labels. Across CAMERA25, REAL275, and HouseCat6D, YOPO achieves state-of-the-art performance among RGB-only methods and narrows the gap to RGB-D systems, with ablations highlighting the importance of 3D-aware matching and bounding-box conditioning. The approach offers a simple, scalable baseline for RGB-only 9D perception and opens avenues for robustness to occlusion, domain shift, and temporal cues in future work.
Abstract
Accurately recovering the full 9-DoF pose of unseen instances within specific categories from a single RGB image remains a core challenge for robotics and automation. Most existing solutions still rely on pseudo-depth, CAD models, or multi-stage cascades that separate 2D detection from pose estimation. Motivated by the need for a simpler, RGB-only alternative that learns directly at the category level, we revisit a longstanding question: Can object detection and 9-DoF pose estimation be unified with high performance, without any additional data? We show that they can with our method, YOPO, a single-stage, query-based framework that treats category-level 9-DoF estimation as a natural extension of 2D detection. YOPO augments a transformer detector with a lightweight pose head, a bounding-box-conditioned translation module, and a 6D-aware Hungarian matching cost. The model is trained end-to-end only with RGB images and category-level pose labels. Despite its minimalist design, YOPO sets a new state of the art on three benchmarks. On the REAL275 dataset, it achieves 79.6% $\rm{IoU}_{50}$ and 54.1% under the $10^\circ$$10{\rm{cm}}$ metric, surpassing prior RGB-only methods and closing much of the gap to RGB-D systems. The code, models, and additional qualitative results can be found on https://mikigom.github.io/YOPO-project-page.
