ECCV 2026 Papers

European Conference on Computer Vision

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2,834papers

Counted from the official paper list; may differ slightly from the number the conference announced.

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    2,80398.9%
  • Other / unlabeled
    311.1%

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Foveated Reasoning: Stateful, Action-based Visual Focusing for Vision-Language Models

Juhong Min, Lazar Valkov, Vitali Petsiuk, Hossein Souri, Deen Dayal Mohan

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Vision–language models benefit from high-resolution images, but the increase in visual-token count incurs high compute overhead. Humans resolve this tension via foveation: a coarse view guides “where to look”, while selectively acquired high-acuity evidence refines “what to think”. We introduce Foveated Reasoner, an autoregressive visionlanguage framework that unifies foveation and reasoning within a single decoding trajectory. Starting from a low-resolution view, the model triggers foveation only when needed, retrieves high-resolution evidence from selected regions, and injects it back into the same decoding trajectory. We train the method with a two-stage pipeline: coldstart supervision to bootstrap foveation behavior, followed by reinforcement learning to jointly improve evidence acquisition and task accuracy while discouraging trivial “see-everything” solutions. Experiments show that the method learns effective foveation policies and achieves stronger accuracy under tight visual-token budgets across multiple vision–language benchmarks.

Poster
What You Ask is What You Ground: Bridging Question Intent to Temporal Evidence for Grounded VideoQA

Jinhwan Seo, Kyu Han, Jumin Lee, Junhyug Noh, Sung-Eui Yoon

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We study a critical yet overlooked failure mode in Grounded Video Question Answering: question-invariant grounding, where models predict nearly identical temporal segments for different questions about the same video. We trace this behavior to two structural limitations in prior common designs: (i) modality isolation that fixes video representations before they receive question semantics, and (ii) weak question injection inside the grounding module. To address this, we propose †Corresponding authors. 2 J. Seo et al. GroundFormer, which conditions video features on question intent before localization via learnable communication tokens that mediate directed visuo-lingual interaction. On top of the question-conditioned features, a factorized MIL cross-attention couples answer selection with temporal evidence under candidate-level supervision, while Gaussian smoothing converts peaked attention into temporally coherent segments. We further introduce a hierarchical multi-modal contrastive loss that aligns video, question, and answer embeddings across a two-pass training pipeline. GroundFormer achieves state-of-the-art grounded VideoQA performance on NExT-GQA and STAR, substantially improving question-discriminative temporal grounding.

Poster
Incentive Noise and Structural Prior Infusion for Multi-Modal Object Re-Identification

Weixiang Zhou, Yuhao Wang, Xingguo Xu, Cong Wang, Weizhen Zhou, Zhixun Su, Jinshan Pan

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Multi-modal object Re-Identification (ReID) benefits from complementary information across heterogeneous imaging modalities. To further enrich semantic representation, text descriptions have recently been incorporated as an additional modality. However, recent visionlanguage approaches often treat text descriptions as clean, deterministic signals and overlook their inherent noise, including modality-mismatched phrases and semantically ambiguous expressions. Moreover, prevailing methods lack explicit mechanisms to reconcile fine-grained structural discrepancies between modalities, even after high-level semantic alignment. To address these challenges, we propose a novel framework centered on Positive-Incentive Noise (π-noise) and structured prompt modulation. First, the Semantic Cross-Modal Modulator harnesses task-aware π-noise, sampled from a distribution conditioned on both visual and text inputs, to perturb global tokens and enable semantics-guided crossmodal compensation. Second, the Structure-Aware Prompt Adapter injects learnable geometric priors via prompts to enhance spatial consistency. Third, the Context-Aware Sparse Fusion module distills structural context to guide adaptive fusion while shielding identity features from noisy local details. Experiments on three multi-modal ReID benchmarks demonstrate the effectiveness and robustness of our approach. The code is available at https://github.com/zw-absin/INSPI.

Poster
Mitigating Radar-Inertial Calibration Ambiguities via SO(3) Manifold Steering

Chunshen Li, Shengpeng Wang, Zitao Ye, Wei Wang

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Reliable Radar-inertial fusion hinges on accurate extrinsic calibration, yet mmWave Radar poses unique calibration ambiguities: sparse and noisy returns, limited angular resolution, and a fundamental lack of stable geometric correspondences. Prior approaches typically rely on dedicated calibration targets, restrictive motion patterns, or strong scene assumptions, limiting their practicality for real-world deployment. In this paper, we present RadarCalib, a targetless, plug-and-play calibration framework that uses rigorous steering on the SO(3) manifold to establish reliable Radar-inertial constraints. Our key insight is that 3D rotational motion naturally induces a temporal synthetic aperture (TSA), which enables recovery of a fine-grained, high-resolution azimuthal spectrum. This TSA-enhanced representation reveals a highly stable rotationdependent azimuthal shift, which we use as a calibration signal to tightly couple Radar observations with IMU preintegration on the SO(3) manifold. Unlike point-based or motion-prior paradigms, RadarCalib establishes motion-consistent alignment in the spectral domain, regularizing SO(3) optimization and avoiding collapse induced by sparse Radar returns. Extensive real-world experiments show that RadarCalib achieves sub-degree rotational accuracy and outperforms state-of-the-art RadarIMU baselines in accuracy, robustness, and computational efficiency. Our self-collected dataset and code is released at https://github.com/ MetaIoT-WHU/RadarCalib.

Poster
Adversarial Attack and Disturbance Detection by Hadamard-Coded Output Representations for Object Detection and Semantic Segmentation

Lucas Görnhardt, Timo Bartels, Niklas Schwarz, Tim Fingscheidt

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Conventional one-hot encodings often yield poorly calibrated models, being overconfident under attack, and letting entropy-based detection algorithms fail. Previous image classification works have demonstrated that Hadamard-coded output representations can improve adversarial robustness. However, attempts to integrate Hadamard codes into semantic segmentation fall far behind state-of-the-art models in mean intersection-over-union performance. Regarding object detection, such output encodings have not yet been investigated at all. Further, no prior art addressed intrinsic codeword inconsistencies or actually exploited intrinsic codeword redundancy. Accordingly, we first derive a novel decoding procedure for Hadamard codewords towards optimal class-wise probabilities, solving the underlying optimization problem by using the projection onto the probability simplex. Second, our optimization delivers a measure of prediction inconsistency. Third, we are the first to show how to exploit these inconsistencies for adversarial attack and disturbance detection. Fourth, we introduce HadamardNet, a framework employing Hadamard codes as output representations for semantic segmentation and object detection models and tasks. We conduct a comprehensive evaluation both on disturbances and adversarial attacks, achieving state-of-the-art perturbation detection performance for both tasks in only a single detection pass, while delivering equivalent or close-by reference performance on clean data. Code is available at https://github.com/ifnspaml/HadamardPerturbationDetection.

Poster
This Looks Distinctly Like That: Grounding Interpretable Recognition in Stiefel Geometry against Neural Collapse

Junhao Jia, Jiaqi Wang, Yunyou Liu, Haodong Jing, Yueyi Wu, Xian Wu, Yefeng Zheng

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Prototype networks provide an intrinsic case-based expla-nation mechanism, but their interpretability is often undermined byprototype collapse, where multiple prototypes degenerate to highly re-dundant evidence. We attribute this failure mode to the terminal dy-namics of Neural Collapse, where cross-entropy optimization suppressesintra-class variance and drives class-conditional features toward a low-dimensional limit. To mitigate this, we propose Adaptive Manifold Pro-totypes (AMP), a framework that leverages Riemannian optimizationon the Stiefel manifold to represent class prototypes as orthonormalbases and make rank-one prototype collapse infeasible by construction.AMP further learns class-specific effective rank via a proximal gradi-ent update on a non-negative capacity vector, and introduces spatialregularizers that reduce rotational ambiguity and encourage localized,non-overlapping part evidence. Extensive experiments on fine-grainedbenchmarks demonstrate that AMP achieves state-of-the-art classifica-tion accuracy while significantly improving causal faithfulness over priorinterpretable models.

Poster
RL from Physical Feedback: Aligning Large Motion Models with Humanoid Control

Junpeng Yue, Zepeng Wang, Jiangxing Wang, Yuxuan Wang, Yu Zhang, Xinrun Xu, Bin Cao, Sipeng Zheng, gang ding, Zongqing Lu

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This paper focuses on a critical challenge in robotics: translating text-driven generated human motions into executable actions for real humanoid robots. While existing text-to-motion (T2M) generation methods achieve semantic alignment between language and motion, they often produce physically infeasible motions unsuitable for real-world deployment. To bridge the gap between T2M and humanoid execution, we propose Reinforcement Learning from Physical Feedback (RLPF), a novel framework that integrates text-conditioned motion generation with motion-conditioned humanoid whole-body control. RLPF employs a low-level motion tracking policy to assess feasibility in physical simulators, providing rewards for (cid:28)ne-tuning the high-level motion generator. Moreover, RLPF introduces an alignment veri(cid:28)cation module to preserve semantic alignment with text instructions. This joint optimization ensures both physical feasibility and text alignment of T2M generators. Furthermore, to overcome the limitation of frozen tracking policy, we propose Hierarchical RLPF, a co-training framework that iteratively optimizes the high-level T2M generator and the low-level tracking policy. Extensive experiments show that RLPF and Hierarchical RLPF greatly outperform baseline methods in generating physically feasible motions while maintaining semantic alignment with text instructions. •

Poster
From Draft to Draft-Free: One-Step Video Object Removal via Privileged Distillation and Fast Planting

Zizhao Chen, Ping Wei, Guang Dai, Jingdong Wang, Mengmeng Wang

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Video object removal is a fundamental yet challenging task in video editing. Despite recent progress, existing methods typically fall into two categories. Traditional approaches based on optical flow or attention mechanisms often introduce noticeable artifacts and yield unnatural results. In contrast, diffusion-based methods improve visual realism but demand multiple denoising steps, limiting their practicality. To address these issues, we propose From-Draft-to-Draft-Free (D2DF), a framework that distills the ability of transforming coarse drafts into refined videos into a one-step video generation model. Within D2DF, a teacher model is trained to refine low-quality removal results (“drafts”) into high-fidelity videos by multiple steps. Then, through Prior-Privileged Consistency Distillation (PPCD), we distill this capability into a student model that performs one-step removal conditioned on the draft. To eliminate draft dependency, we introduce a Self-Guided Fast Planting (SGFP) module based on our Temporal Masked Transformer that autonomously generates scene-consistent pseudo-drafts in latent space, enabling a fully draft-free one-step model. Extensive experiments show that both draft-conditioned and draft-free versions achieve state-of-the-art performance on multiple metrics, surpassing traditional and multi-step generative methods in both quality and efficiency. The denoising process for a single video takes only about 1 second.

Poster
MambaRaw: Selective State Space Modeling for Efficient 4K RAW Image Reconstruction

Peize Li, Fanhu Zeng, Tongda Xu, Xinjie Zhang, Xingtong Ge, Haotian Zhang, Xingguo Xu, Yan Wang

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In-camera JPEG previews are ubiquitous in raw image formats and provide an sRGB reference at negligible storage cost. Although existing metadata-based reconstruction frameworks can exploit this side information when recovering raw images, their context models often become computationally expensive especially at high resolution, e.g., 4K raw image, given that attention mechanisms scale quadratically with feature maps, hindering its practical application. To address these limitations, we propose MambaRaw, a JPEG-conditioned metadatabased raw image reconstruction framework that uses State Space Models (SSMs) to estimate entropy parameters efficiently. Our key contribution comprises a Spatial-Energy Coupled Context Modeling mechanism with two lightweight modules: (1) TileMambaBlock, which performs Mambastyle selective scanning only on information-dense tiles to improve the efficiency; and (2) Energy-Aware Refinement (EAR), an identity-initialized residual module that enhance feature representation to match the longtail energy distribution of raw signals. Extensive experiments on three camera datasets (Sony, Olympus, Samsung) show consistent improvements over strong metadata-based baselines and set a new state of the art for JPEG-guided raw reconstruction with great efficiency. Notably, at low metadata bitrates, MambaRaw increases PSNR by 1.2–1.4 dB and reduces end-to-end coding latency by about 9%. Code is released at https://github.com/Peizeli1/MambaRaw.

Poster
Multi-View Foundation Models

Leo Segre, Or Hirschorn, Shai Avidan

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Foundation models are vital tools in various Computer Vision applications. They take as input a single RGB image and output a deep feature representation that is useful for various applications. However, in case we have multiple views of the same 3D scene, they operate on each image independently and do not always produce consistent features for the same 3D point. We propose a way to lift a Foundation Model into a Multi-View Foundation Model. Such a model takes as input a set of images and outputs a feature map for each image such that the features of corresponding points are as consistent as possible. This approach bypasses the need to build a consistent 3D model of the features. Specifically, we show how to augment any Transformer-based foundation model (i.e., DINO, SAM, CLIP) with intermediate 3D-attention layers that help match features across different views. Quantitative evaluations demonstrate that our approach achieves superior 3D-awareness while best preserving the native semantic space of the original foundation model, outperforming existing lifting techniques.

Poster
PanoLess: Environment Reconstruction from Partial Reflective Views

Ahitagni Das, Ashok Veeraraghavan, Vivek Boominathan

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Reflections from shiny objects and glass façades naturally extend the field of view of a camera, capturing the surrounding environment without the need to pan the camera or acquire a full panorama. We propose PanoLess, a Gaussian-splat–based framework that reconstructs the surrounding environment as a distant-illumination map from images captured on only one side of a reflective surface. PanoLess leverages surface-aligned 2D Gaussian splats with deferred shading to recover accurate per-pixel normals and reflection cues, which are fused into a neural cubemap representation of the environment. In addition, PanoLess produces a visibility map that explicitly denotes which regions of the environment are supported by the partial reflective observations. Unlike existing inverse-rendering and reflection-aware Gaussian-splatting approaches—which typically require full 360◦ coverage and struggle under incomplete views—PanoLess enables consistent, physically grounded illumination estimation from partial-view input. We show that PanoLess achieves high-fidelity and geometrically consistent environment reconstruction, outperforming reflection-aware baselines on a new custom synthetic benchmark and publicly available datasets, and demonstrating generalization to real-world reflective captures.

Poster
Score-Based Matching with Target Guidance for Cryo-EM Denoising

Xiaoqi Wu, Xueying Zhan, Wen Li, Junhao Wu, Xin Huang, Ke Ni, Min Xu

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Cryo-electron microscopy (cryo-EM) enables single-particle analysis of biological macromolecules under strict low-dose imaging conditions, but the resulting micrographs often exhibit extremely low signalto-noise ratios and weak particle visibility. Image denoising is therefore an important preprocessing step for downstream cryo-EM analysis, including particle picking, 2D classification, and 3D reconstruction. Existing cryo-EM denoising methods are commonly trained with pixel-wise or Noise2Noise-style objectives, which can improve visual quality but do not explicitly account for structural consistency required by downstream analysis. In this work, we propose a score-based denoising framework for cryo-EM that learns the clean-data score to recover particle signals while better preserving structural information. Building on this formulation, we further introduce a target-guided variant that incorporates referencedensity guidance to stabilize score learning under weak and ambiguous signal conditions. Rather than simply amplifying particle-like responses, our framework better suppresses structured low-frequency background, which improves particle–background separability for downstream analysis. Experiments on multiple cryo-EM datasets show that our score-based methods consistently improve downstream particle picking and produce more structure-consistent 3D reconstructions. Experiments on multiple cryo-EM datasets show that our methods improve downstream particle picking and produce more structure-consistent reconstructions. Our code is available at https://github.com/xulabs/aitom.

Poster
PhysChoreo: Physics-Controllable Video Generation with Part-Aware Semantic Grounding

Haoze Zhang, Tianyu Huang, Zichen Wan, Xiaowei Jin, Hongzhi Zhang, Hui Li, Wangmeng Zuo

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While recent video generation models have achieved significant visual fidelity, they often suffer from the lack of explicit physical controllability and plausibility. To address this, some recent studies attempted to guide video generation with physics-based rendering. However, these methods face inherent challenges in accurately modeling complex physical properties and effectively controlling the resulting physical behavior over extended temporal sequences. In this work, we introduce PhysChoreo, a framework that can generate videos with diverse controllability and physical realism from a single image. Our method consists of two stages: first, it estimates the static initial physical properties of all objects in the image through part-aware physical property reconstruction. Then, through temporally instructed and physically editable simulation, it synthesizes high-quality videos with rich dynamic behaviors and physical realism. Experimental results show that PhysChoreo can generate videos with rich behaviors and physical realism, outperforming state-of-the-art methods on multiple evaluation metrics.

Poster
Unified Multi-Layer Subspace Modeling for Cross-Domain OOD Detection

Gerhard Krumpl, Henning Avenhaus, Horst Possegger

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Out-of-Distribution (OOD) detection remains a fundamental challenge for neural networks, whose predictions can be overconfident on inputs that deviate from the training distribution. Most post-hoc OOD detection methods derive scores from a single representation level (e.g., logits or penultimate features) or combine multiple layers via depth selection or OOD-calibrated weighting. However, because OOD shifts are diverse, the most informative representation level can vary strongly across OOD types and domains, making fixed-layer choices and OOD-calibrated aggregation brittle. In this paper, we propose PRISM (Projected Representation with Intermediate-layer Subspace Modeling), a model-agnostic post-hoc OOD detection method that models a unified multi-layer feature representation rather than aggregating independently scored layers. PRISM fuses intermediate and deep features into a single hierarchical embedding, estimates an in-distribution (ID) principal subspace, and then combines two complementary signals: (i) a class-conditional Mahalanobis distance in the projected subspace and (ii) the residual energy orthogonal to the learned manifold. This simple design avoids OOD-tuned layer weighting while capturing both in-subspace semantic deviations and offsubspace anomalies. Across diverse benchmarks spanning natural images, medical imaging, and industrial visual inspection, PRISM achieves consistent state-of-the-art cross-domain OOD detection performance with a single default configuration across all evaluated domains and architectures. We further show that PRISM incurs minimal inference overhead, making it practical for real-world deployment.

Poster
TEX-Drive: Temporal Perception Meets Experience-Guided Mixture-of-Experts for End-to-End Autonomous Driving

Yitong Li, Xuchong Zhang, Fanjie Kong, Weihuang Chen, Haonan Hou, Hongbin Sun

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Human driving behavior embodies two core cognitive mechanisms: experiential reasoning and functional specialization. However, existing end-to-end autonomous driving (E2E-AD) frameworks typically model these two processes separately, often resulting in inconsistent decisions under long-horizon or dynamic conditions. To address this issue, we propose TEX-Drive, a unified E2E framework that integrates temporal perception with an experience-driven Mixture-of-Experts, achieving coordinated temporal perception–guided experience routing. Specifically, the temporal perception unit employs explicit key-frame selection to fuse critical information from both historical and current inputs, forming a temporally coherent scene representation. Building upon this, the experience-driven Mixture-of-Experts planning retrieves expert modules from a long-term memory space according to contextual similarity, dynamically routing the most relevant experts to adaptively generate future trajectories. This design enables the decision-making process to maintain temporal consistency while being guided by accumulated experiential knowledge. Extensive experiments on the Bench2Drive benchmark show that TEX-Drive consistently improves driving score, route completion, and behavioral robustness, substantially outperforming existing state-ofthe-art methods.

Poster
Large-Scale Light Field Synthesis from Videos Enables Geometrically Consistent Bokeh Editing

Haoming Cai, Zhoutong Zhang, Christopher Metzler, Shumian Xin

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Focus and depth of field (DoF) define where attention falls and how much of a scene appears sharp. Adjusting both after capture provides creators two-dimensional control over visual attention. However, existing focus and DoF editing tools fail when applied to scenes with complex geometries, such as reflections and fine features. This failure is a result of fundamental limitations in existing training data generation pipelines: current pipelines either sacrifice geometric fidelity for scalability, or sacrifice scalability for geometric fidelity. To address this, we present Vid2Bokeh, a scalable bokeh data acquisition pipeline that reconstructs dense 25×25 light fields from casual videos via feed-forward 3D reconstruction, bypassing depth estimation entirely and avoiding the geometric errors it introduces. The resulting Vid2Bokeh Dataset comprises over 100K light fields on diverse real-world scenes, simultaneously achieving scene diversity, optical density, and geometric fidelity that no existing bokeh dataset or bokeh data acquisition pipeline provides. By training on this geometrically faithful bokeh data, we introduce a diffusion model for full bidirectional focus–DoF editing that outperforms depth-based baselines on complex geometries. This result demonstrates that geometric fidelity in large-scale training data is the key to geometrically consistent bokeh editing.

Poster
UMO: Unified In-Context Learning Unlocks Motion Foundation Model Priors

Xiaoyan Cong, Zekun Li, Zhiyang Dou, Hongyu Li, Omid Taheri, Chuan Guo, Abhay Mittal, Sizhe An, Taku Komura, Wojciech Matusik, Michael Black, Srinath Sridhar

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Large-scale foundation models (LFMs) have recently made impressive progress in text-to-motion generation by learning strong generative priors from massive 3D human motion datasets and paired text descriptions. However, how to effectively and efficiently leverage such single-purpose motion LFMs, i.e., text-to-motion synthesis, in more diverse cross-modal and in-context motion generation downstream tasks remains largely unclear. Prior work typically adapts pretrained generative priors to individual downstream tasks in a task-specific manner. In contrast, our goal is to unlock such priors to support a broad spectrum of downstream motion generation tasks within a single unified framework. To bridge this gap, we present UMO, a simple yet general unified formulation that casts diverse downstream tasks into compositions of atomic per-frame operations, enabling in-context adaptation to unlock the generative priors of pretrained DiT-based motion LFMs. Specifically, UMO introduces three learnable frame-level meta-operation embeddings to specify per-frame intent and employs lightweight temporal fusion to inject in-context cues into the pretrained backbone, with negligible runtime overhead compared to the base model. With this design, UMO finetunes the pretrained model, originally limited to text-tomotion generation, to support diverse previously unsupported tasks, including temporal inpainting, text-guided motion editing, text-serialized geometric constraints, and multi-identity reaction generation. Experiments demonstrate that UMO consistently outperforms task-specific and training-free baselines across a wide range of benchmarks, despite using a single unified model. Code and models will be publicly available.

Poster
TAIHRI: Task-Aware 3D Human Keypoints Localization for Close-Range Human-Robot Interaction

Ao Li, Yonggen Ling, Yiyang Lin, Yuji Wang, Yong Deng, Yansong Tang

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Accurate 3D human keypoints localization is a critical technology enabling robots to achieve natural and safe physical interaction with users. Conventional 3D human keypoints estimation methods primarily focus on the whole-body reconstruction quality relative to the root joint. However, in practical human-robot interaction (HRI) scenarios, robots are more concerned with the precise metric-scale spatial localization of task-relevant body parts under the egocentric camera 3D coordinate. We propose TAIHRI, the first Vision-Language Model (VLM) tailored for close-range HRI perception, capable of understanding users’ motion commands and directing the robot’s attention to the most taskrelevant keypoints. By quantizing 3D keypoints into a finite interaction space, TAIHRI precisely localize the 3D spatial coordinates of critical body parts by 2D keypoint reasoning via next token prediction, and seamlessly adapt to downstream tasks such as natural language control or global space human mesh recovery. Experiments on egocentric interaction benchmarks demonstrate that TAIHRI achieves superior estimation accuracy for task-critical body parts. We believe TAIHRI opens new research avenues in the field of embodied human-robot interaction. Code is available at: https://github.com/Tencent/TAIHRI.

Poster
MixGRPO: Unlocking Flow-based GRPO Efficiency with Mixed ODE-SDE

Junzhe Li, Yutao Cui, Tao Huang, Chuxuan Zeng, Weijie Kong, Yinping Ma, Chun Fan, Miles Yang, Zhao Zhong, Liefeng Bo

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Although GRPO substantially improves flow-matching models for human preference alignment in vision generation, mainstream methods such as DanceGRPO rely on Global-Stochastic Di!erential Equations (SDE) sampling across full timesteps in the Markov Decision Process (MDP), which remains computationally ine"cient. In this paper, we propose MixGRPO, a novel framework that leverages the flexibility of mixed sampling strategies through the integration of SDE and Ordinary Di!erential Equations (ODE). This redesign streamlines optimization within the MDP, delivering gains in both generation performance and training e!ciency. Specifically, MixGRPO introduces a sliding window mechanism, using SDE sampling and GRPO-guided optimization only within the window, while applying ODE sampling outside. This design confines sampling randomness to the time-steps within the window, thereby reducing the optimization overhead, and allowing for more focused gradient updates to accelerate convergence. Additionally, as time-steps beyond the sliding window are not involved in optimization, higher-order solvers are supported for faster sampling. So we present a faster variant, termed MixGRPO-Flash, which further improves training e"ciency while achieving comparable performance. MixGRPO exhibits substantial gains across multiple dimensions of human preference alignment, outperforming DanceGRPO in both e!ectiveness and e"- ciency, with nearly 50% lower training time. Notably, MixGRPOFlash further reduces training time by 71%.5

Poster
ConsiSpace: Learning Geometric Consistency Matters for Video Spatial Reasoning

Ting Huang, Zhenyu Zhang, Wenyuan Huang, Hao Tang, Jian Yang

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Video spatial reasoning is essential for navigation-oriented perception and long-video question answering, where models must infer spatial relations across long horizons under changing viewpoints. However, existing multimodal large language models (MLLMs) remain largely semantic-centric, and often fail to reliably aggregate consistent spatial evidence from redundant video observations, leading to inefficient or unstable reasoning. To address these issues, we propose ConsiSpace, a geometry-consistency-aware framework for geometry-sensitive video spatial reasoning that turns spatial consistency into both an evidence organization principle and an explicit post-SFT learning signal. We build a geometry-consistent memory (GCM) including implicit evidence tokens and explicit geometric cues, and leverage efficient organization strategies to compactly preserve task-related spatial evidence. Furthermore, we utilize unified consistency self-supervised reinforcement learning (UCSSRL) after supervised fine-tuning to improve cross-view stability, with answer-, metric-, and topology-consistency rewards. Extensive experiments on three spatial-reasoning benchmarks, VSI-Bench, OSI-Bench, and MMSI-Video-Bench, show consistent gains, improving the average score by 12.6 points over the strongest baselines.

Poster