Proxy3D: Efficient 3D Representations for Vision-Language Models via Semantic Clustering and Alignment
On the map: Multimodal LLMs / vision-language models → Embodied and 3D vision-language models
Abstract (arXiv)
Spatial intelligence in vision-language models (VLMs) attracts research interest with the practical demand to reason in the 3D world.Despite promising results, most existing methods follow the conventional 2D pipeline in VLMs and use pixel-aligned representations for the vision modality. However, correspondence-based models with implicit 3D scene understanding often fail to achieve spatial consistency, and representation-based models with 3D geometric priors lack efficiency in vision sequence serialization. To address this, we propose a Proxy3D method with compact yet comprehensive 3D proxy representations for the vision modality. Given only video frames as input, we employ semantic and geometric encoders to extract scene features and then perform their semantic-aware clustering to obtain a set of proxies in the 3D space. For representation alignment, we further curate the SpaceSpan dataset and apply multi-stage training to adopt the proposed 3D proxy representations with the VLM. When using shorter sequences for vision information, our method achieves competitive or state-of-the-art performance in 3D visual question answering, visual grounding and general spatial intelligence benchmarks.
Key facts. Cited by 2 papers in the map (data through 7 Oct 2026). Placed in Embodied and 3D vision-language models, one of 16 directions in Multimodal LLMs / vision-language models. Builds on 53 of its 57 references that are in the map. First posted on arXiv 8 May 2026.
Builds on
53 of 57 references.
Closest ancestors · 14
Same direction, newest first
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- 2025Spatial-MLLM: Boosting MLLM Capabilities in Visual-based Spatial Intelligence29 May
- 2025VLM-3R: Vision-Language Models Augmented with Instruction-Aligned 3D Reconstruction26 May
- 2025Ross3D: Reconstructive Visual Instruction Tuning with 3D-Awareness2 Apr
- 2025SpaceR: Reinforcing MLLMs in Video Spatial Reasoning2 Apr
- 2025GPT4Scene: Understand 3D Scenes from Videos with Vision-Language Models2 Jan
- 2024Thinking in Space: How Multimodal Large Language Models See, Remember, and Recall Spaces18 Dec
- 2024Video-3D LLM: Learning Position-Aware Video Representation for 3D Scene Understanding30 Nov
- 2024Coarse Correspondences Boost Spatial-Temporal Reasoning in Multimodal Language Model1 Aug
- 2024ShapeLLM: Universal 3D Object Understanding for Embodied Interaction27 Feb
2 more
Other references · 39
- 2021High-Resolution Image Synthesis with Latent Diffusion Modelscited by 18,694
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- 2021RoFormer: Enhanced Transformer with Rotary Position Embeddingcited by 4,581
- 2024GPT-4o System Cardcited by 4,467
- 2024Qwen2-VL: Enhancing Vision-Language Model's Perception of the World at Any Resolutioncited by 4,151
- 2024Gemini 1.5: Unlocking multimodal understanding across millions of tokens of contextcited by 3,175
- 2017ScanNet: Richly-annotated 3D Reconstructions of Indoor Scenescited by 3,088
- 2024SAM 2: Segment Anything in Images and Videoscited by 2,784
- 2024LLaVA-OneVision: Easy Visual Task Transfercited by 2,669
- 2023InternVL: Scaling up Vision Foundation Models and Aligning for Generic Visual-Linguistic Taskscited by 2,534
- 2025VGGT: Visual Geometry Grounded Transformercited by 1,475
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- 2023Point Transformer V3: Simpler, Faster, Strongercited by 579
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- 2019ScanRefer: 3D Object Localization in RGB-D Scans using Natural Languagecited by 446
- 2021ARKitScenes: A Diverse Real-World Dataset For 3D Indoor Scene Understanding Using Mobile RGB-D Datacited by 442
- 2023An Embodied Generalist Agent in 3D Worldcited by 355
- 2021ScanQA: 3D Question Answering for Spatial Scene Understandingcited by 340
- 2023PointLLM: Empowering Large Language Models to Understand Point Cloudscited by 326
- 2022SQA3D: Situated Question Answering in 3D Scenescited by 303
- 2016Segmentation from Natural Language Expressionscited by 257
- 2016Modeling Context Between Objects for Referring Expression Understandingcited by 250
- 2019Action Genome: Actions as Composition of Spatio-temporal Scene Graphscited by 249
- 2020Scan2Cap: Context-aware Dense Captioning in RGB-D Scanscited by 215
- 2023Multi3DRefer: Grounding Text Description to Multiple 3D Objectscited by 142
- 2023PointGPT: Auto-regressively Generative Pre-training from Point Cloudscited by 115
- 2023OctFormer: Octree-based Transformers for 3D Point Cloudscited by 105
- 2021Learnable Fourier Features for Multi-Dimensional Spatial Positional Encodingcited by 93
- 2024ChatScene: Knowledge-Enabled Safety-Critical Scenario Generation for Autonomous Vehiclescited by 92
- 2023FlatFormer: Flattened Window Attention for Efficient Point Cloud Transformercited by 72
- 2024Unifying 3D Vision-Language Understanding via Promptable Queriescited by 70
- 2025SpatialCoT: Advancing Spatial Reasoning through Coordinate Alignment and Chain-of-Thought for Embodied Task Planningcited by 62
- 2024MMScan: A Multi-Modal 3D Scene Dataset with Hierarchical Grounded Language Annotationscited by 40
- 20243DGraphLLM: Combining Semantic Graphs and Large Language Models for 3D Scene Understandingcited by 26
- 2025SplatTalk: 3D VQA with Gaussian Splattingcited by 24
- 2025Unveiling the Mist over 3D Vision-Language Understanding: Object-centric Evaluation with Chain-of-Analysiscited by 22
- 2025Descrip3D: Enhancing Large Language Model-based 3D Scene Understanding with Object-Level Text Descriptionscited by 3
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Citing papers per year: 2026: 2.
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