OneCAT: Decoder-Only Auto-Regressive Model for Unified Understanding and Generation
On the map: Mixture-of-experts → Multimodal MoE models
Abstract (arXiv)
We introduce OneCAT, a unified multimodal model that seamlessly integrates understanding, generation, and editing within a novel, pure decoder-only transformer architecture. Our framework uniquely eliminates the need for external components such as Vision Transformers (ViT) or vision tokenizer during inference, leading to significant efficiency gains, especially for high-resolution inputs. This is achieved through a modality-specific Mixture-of-Experts (MoE) structure trained with a single autoregressive (AR) objective, which also natively supports dynamic resolutions. Furthermore, we pioneer a multi-scale visual autoregressive mechanism within the Large Language Model (LLM) that drastically reduces decoding steps compared to diffusion-based methods while maintaining state-of-the-art performance. Our findings demonstrate the powerful potential of pure autoregressive modeling as a sufficient and elegant foundation for unified multimodal intelligence. As a result, OneCAT sets a new performance standard, outperforming existing open-source unified multimodal models across benchmarks for multimodal generation, editing, and understanding.
Key facts. Cited by 50 papers in the map (data through 7 Oct 2026). Placed in Multimodal MoE models, one of 12 directions in Mixture-of-experts. Builds on 97 of its 111 references that are in the map. First posted on arXiv 3 Sep 2025.
Builds on
97 of 111 references.
References · 97
- 2021Learning Transferable Visual Models From Natural Language Supervisioncited by 33,456
- 2023Visual Instruction Tuningcited by 7,792
- 2023BLIP-2: Bootstrapping Language-Image Pre-training with Frozen Image Encoders and Large Language Modelscited by 6,069
- 2022Classifier-Free Diffusion Guidancecited by 5,717
- 2025Qwen2.5-VL Technical Reportcited by 5,418
- 2024Qwen2.5 Technical Reportcited by 4,713
- 2024GPT-4o System Cardcited by 4,467
- 2022Flamingo: a Visual Language Model for Few-Shot Learningcited by 4,337
- 2023SDXL: Improving Latent Diffusion Models for High-Resolution Image Synthesiscited by 4,290
- 2024Qwen2-VL: Enhancing Vision-Language Model's Perception of the World at Any Resolutioncited by 4,151
- 2024Scaling Rectified Flow Transformers for High-Resolution Image Synthesiscited by 4,094
- 2023Sigmoid Loss for Language Image Pre-Trainingcited by 3,048
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- 2022InstructPix2Pix: Learning to Follow Image Editing Instructionscited by 2,591
- 2023InternVL: Scaling up Vision Foundation Models and Aligning for Generic Visual-Linguistic Taskscited by 2,534
- 2016Making the V in VQA Matter: Elevating the Role of Image Understanding in Visual Question Answeringcited by 2,498
- 2023Qwen-VL: A Versatile Vision-Language Model for Understanding, Localization, Text Reading, and Beyondcited by 2,179
- 2023MMBench: Is Your Multi-modal Model an All-around Player?cited by 2,105
- 2023MMMU: A Massive Multi-discipline Multimodal Understanding and Reasoning Benchmark for Expert AGIcited by 2,044
- 2025InternVL3: Exploring Advanced Training and Test-Time Recipes for Open-Source Multimodal Modelscited by 1,769
- 2019Towards VQA Models That Can Readcited by 1,696
- 2023MathVista: Evaluating Mathematical Reasoning of Foundation Models in Visual Contextscited by 1,582
- 2024Expanding Performance Boundaries of Open-Source Multimodal Models with Model, Data, and Test-Time Scalingcited by 1,573
- 2021LAION-400M: Open Dataset of CLIP-Filtered 400 Million Image-Text Pairscited by 1,544
- 2022ChartQA: A Benchmark for Question Answering about Charts with Visual and Logical Reasoningcited by 1,449
- 2025InternVL3.5: Advancing Open-Source Multimodal Models in Versatility, Reasoning, and Efficiencycited by 1,419
- 2020DocVQA: A Dataset for VQA on Document Imagescited by 1,288
- 2023MM-Vet: Evaluating Large Multimodal Models for Integrated Capabilitiescited by 1,221
- 2021Conceptual 12M: Pushing Web-Scale Image-Text Pre-Training To Recognize Long-Tail Visual Conceptscited by 1,209
- 2025SigLIP 2: Multilingual Vision-Language Encoders with Improved Semantic Understanding, Localization, and Dense Featurescited by 1,127
- 2019OK-VQA: A Visual Question Answering Benchmark Requiring External Knowledgecited by 1,114
- 2023Kosmos-2: Grounding Multimodal Large Language Models to the Worldcited by 1,075
- 2024How Far Are We to GPT-4V? Closing the Gap to Commercial Multimodal Models with Open-Source Suitescited by 1,033
- 2024Visual Autoregressive Modeling: Scalable Image Generation via Next-Scale Predictioncited by 1,005
- 2023ShareGPT4V: Improving Large Multi-Modal Models with Better Captionscited by 1,000
- 2023GenEval: An Object-Focused Framework for Evaluating Text-to-Image Alignmentcited by 946
- 2023SEED-Bench: Benchmarking Multimodal LLMs with Generative Comprehensioncited by 929
- 2024Chameleon: Mixed-Modal Early-Fusion Foundation Modelscited by 904
- 2023A Survey on Multimodal Large Language Modelscited by 898
- 2025Emerging Properties in Unified Multimodal Pretrainingcited by 855
- 2016A Diagram Is Worth A Dozen Imagescited by 793
- 2025Janus-Pro: Unified Multimodal Understanding and Generation with Data and Model Scalingcited by 787
- 2024Emu3: Next-Token Prediction is All You Needcited by 761
- 2024Show-o: One Single Transformer to Unify Multimodal Understanding and Generationcited by 734
- 2023MagicBrush: A Manually Annotated Dataset for Instruction-Guided Image Editingcited by 615
- 2024Transfusion: Predict the Next Token and Diffuse Images with One Multi-Modal Modelcited by 468
- 2024ELLA: Equip Diffusion Models with LLM for Enhanced Semantic Alignmentcited by 455
- 2024Janus: Decoupling Visual Encoding for Unified Multimodal Understanding and Generationcited by 447
- 2021InfographicVQAcited by 430
- 2025Step1X-Edit: A Practical Framework for General Image Editingcited by 417
50 most cited of 97 All 97 (JSON)
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