Oral Session
Oral Session 2A: 3D Reconstruction
MAMMA: Markerless Accurate Multi-person Motion Acquisition
Hanz Cuevas Velasquez ⋅ Anastasios Yiannakidis ⋅ Soyong Shin ⋅ Giorgio Becherini ⋅ Markus Höschle ⋅ Joachim Tesch ⋅ Taylor Obersat ⋅ Tsvetelina Alexiadis ⋅ Eni Halilaj ⋅ Michael J. Black
We present MAMMA, a markerless motion-capture pipeline that accurately recovers SMPL-X parameters from multi-view video.Traditional motion-capture systems rely on physical markers. Although they offer high accuracy, their requirements of specialised hardware, manual marker placement, and extensive post-processing make them costly and time-consuming. Recent learning-based methods attempt to overcome these limitations, but most are designed for single-person capture, rely on sparse keypoints, or struggle with occlusions and physical interactions. In this work, we introduce a method that predicts dense 2D surface landmarks conditioned on segmentation masks, enabling person-specific correspondence estimation even under heavy occlusion. We employ a novel architecture that exploits learnable queries for each landmark. We demonstrate that our approach can handle complex person--person interaction and offers greater accuracy than existing methods. To train our network, we construct a large, synthetic multi-view dataset combining human motions from diverse sources, including extreme poses, hand motions, and close interactions. Our dataset yields high-variability synthetic sequences with rich body contact and occlusion, and includes SMPL-X ground-truth annotations with dense 2D landmarks.The result is a system capable of accurately capturing human motion without the need for markers. Our approach offers competitive reconstruction quality compared to commercial marker-based motion-capture solutions, without the extensive manual cleanup. Finally, we address the absence of common benchmarks for dense-landmark prediction and markerless motion capture by introducing two evaluation settings built from real multi-view sequences. We will release our dataset, method, code, and model weights for research purposes.
Natural Human Motion Recovery by Aligning High-Order Temporal Dynamics from Monocular Videos
Dingkun Wei ⋅ Zehong Shen ⋅ Yan Xia ⋅ Yujun Shen ⋅ Georgios Pavlakos ⋅ Xiaowei Zhou
Human motion recovered from monocular videos often appears overly smooth or dynamically inconsistent, even when joint positions are numerically accurate. We observe that this limitation stems from the absence of reliable high-order temporal cues—velocity and acceleration—which are essential for reconstructing motion that exhibits realistic momentum, timing, and high-frequency detail.We introduce HTD-Refine, a post-processing framework that augments existing Human Motion Recovery (HMR) pipelines using explicitly estimated high-order temporal dynamics. At the core of our system is PVA-Net, a temporal transformer that infers per-joint 2D positions, velocities, and accelerations directly from a monocular video. These predicted dynamics serve as soft yet informative constraints in a global optimization procedure that refines camera-space and world-space trajectories, significantly reducing jitter, suppressing oversmoothing, and restoring physically plausible motion profiles.Extensive experiments on challenging in-the-wild benchmarks show that HTD-Refine consistently improves state-of-the-art HMR methods, yielding more accurate global trajectories and substantially more natural motion dynamics. Our results highlight the critical role of high-order temporal modeling in advancing monocular human motion recovery.
PoseGAM: Robust Unseen Object Pose Estimation via Geometry-Aware Multi-View Reasoning
Jianqi Chen ⋅ Biao Zhang ⋅ Xiangjun Tang ⋅ Peter Wonka
6D object pose estimation, which predicts the transformation of an object relative to the camera, remains challenging for unseen objects. Existing approaches typically rely on explicitly constructing feature correspondences between the query image and either the object model or template images. In this work, we propose PoseGAM, a geometry-aware multi-view framework that directly predicts object pose from a query image and multiple template images, eliminating the need for explicit matching. Built upon recent multi-view-based foundation model architectures, the method integrates object geometry information through two complementary mechanisms: explicit point-based geometry and learned features from geometry representation networks. In addition, we construct a large-scale synthetic dataset containing more than 190k objects under diverse environmental conditions to enhance robustness and generalization. Extensive evaluations across multiple benchmarks demonstrate our state-of-the-art performance, yielding an average AR improvement of 5.1% over prior methods and achieving up to 17.6% gains on individual datasets, indicating strong generalization to unseen objects.
SAM 3D Body: Robust Full-Body Human Mesh Recovery
Xitong Yang ⋅ Devansh Kukreja ⋅ Don Pinkus ⋅ Taosha Fan ⋅ Jinhyung Park ⋅ Soyong Shin ⋅ Jinkun Cao ⋅ Jia-Wei Liu ⋅ Nicolás Ugrinovic ⋅ Anushka Sagar ⋅ Jitendra Malik ⋅ Matt Feiszli ⋅ Piotr Dollár ⋅ Kris Kitani
We introduce SAM 3D Body (3DB), a promptable model for single-image full-body 3D human mesh recovery (HMR) that demonstrates state-of-the-art performance, with strong generalization and consistent accuracy in diverse in-the-wild conditions. 3DB estimates the human pose of the body, feet, and hands. It is the first model to use a new parametric mesh representation, Momentum Human Rig (MHR), which decouples skeletal pose and body shape. 3DB employs an encoder–decoder architecture and supports auxiliary prompts, including 2D keypoints and masks, enabling user-guided inference similar to the SAM family of models. We derive high-quality annotations from a multi-stage annotation pipeline that uses various combinations of manual keypoint annotation, differentiable optimization, multi-view geometry, and dense keypoint detection. Our data engine efficiently selects and processes data to ensure data diversity, collecting unusual poses and rare imaging conditions. We present a new evaluation dataset organized by pose and appearance categories, enabling nuanced analysis of model behavior. Our experiments demonstrate superior generalization and substantial improvements over prior methods in both qualitative user preference studies and traditional quantitative analysis. Both 3DB and MHR are open-source.
SAM 3D: 3Dfy Anything in Images
Xingyu Chen ⋅ Fu-Jen Chu ⋅ Pierre Gleize ⋅ Kevin J Liang ⋅ Alexander Sax ⋅ Hao Tang ⋅ Weiyao Wang ⋅ Michelle Guo ⋅ Thibaut Hardin ⋅ Xiang Li ⋅ Aohan Lin ⋅ Jia-Wei Liu ⋅ Ziqi Ma ⋅ Anushka Sagar ⋅ Bowen Song ⋅ Xiaodong Wang ⋅ Jianing "Jed" Yang ⋅ Bowen Zhang ⋅ Piotr Dollár ⋅ Georgia Gkioxari ⋅ Matt Feiszli ⋅ Jitendra Malik
We present SAM 3D, a generative model for visually grounded 3D object reconstruction, predicting geometry, texture, and layout from a single image. SAM 3D excels in natural images, where occlusion and scene clutter are common and visual recognition cues from context play a larger role. We achieve this with a human- and model-in-the-loop pipeline for annotating object shape, texture, and pose, providing visually grounded 3D reconstruction data at unprecedented scale. We learn from this data in a modern, multi-stage training framework that combines synthetic pretraining with real-world alignment, breaking the 3D "data barrier". We obtain significant gains over recent work, with at least a $5:1$ win rate in human preference tests on real-world objects and scenes. We will release our code and model weights, an online demo, and a new challenging benchmark for in-the-wild 3D object reconstruction.
SPARK: Sim-ready Part-level Articulated Reconstruction with VLM Knowledge
Yumeng He ⋅ Ying Jiang ⋅ Jiayin Lu ⋅ Yin Yang ⋅ Chenfanfu Jiang
Articulated 3D objects are critical for embodied AI, robotics, and interactive scene understanding, yet creating simulation-ready assets remains labor-intensive and requires expert modeling of part hierarchies and motion structures. We introduce SPARK, a framework for reconstructing physically consistent, kinematic part-level articulated objects from a single RGB image. Given an input image, we first leverage VLMs to extract coarse URDF parameters and generate part-level reference images. We then integrate the part-image guidance and the inferred structure graph into a generative diffusion transformer to synthesize consistent part and complete shapes of articulated objects. To further refine the URDF parameters, we incorporate differentiable forward kinematics and differentiable rendering to optimize joint types, axes, and origins under VLM-generated open-state supervision. Extensive experiments show that SPARK produces high-quality, simulation-ready articulated assets across diverse categories, enabling downstream applications such as robotic manipulation and interaction modeling.