--- license: apache-2.0 tags: - muiltimodal - discrete-flow-matching - unifed-model --- ## 1. Introduction The rapid progress of large language models (LLMs) has catalyzed the emergence of multimodal large language models (MLLMs) that unify visual understanding and image generation within a single framework. However, most existing MLLMs rely on autoregressive (AR) architectures, which impose inherent limitations on future development, such as the raster-scan order in image generation and restricted reasoning abilities in causal context modeling. In this work, we challenge the dominance of AR-based approaches by introducing **FUDOKI**, a unified multimodal model purely based on discrete flow matching, as an alternative to conventional AR paradigms. By leveraging metric-induced probability paths with kinetic optimal velocities, our framework goes beyond the previous masking-based corruption process, enabling iterative refinement with self-correction capability and richer bidirectional context integration during generation. To mitigate the high cost of training from scratch, we initialize FUDOKI from pre-trained AR-based MLLMs and adaptively transition to the discrete flow matching paradigm. Experimental results show that FUDOKI achieves performance comparable to state-of-the-art AR-based MLLMs across both visual understanding and image generation tasks, highlighting its potential as a foundation for next-generation unified multimodal models. Furthermore, we show that applying test-time scaling techniques to FUDOKI yields significant performance gains, further underscoring its promise for future enhancement through reinforcement learning.
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[FUDOKI: Discrete Flow-based Unified Understanding and Generation via Kinetic-Optimal Velocities](https://arxiv.org/abs/2505.20147). ## 2. Quick Start Please refer to [**Github Repository**](https://github.com/fudoki-hku/FUDOKI) ## 3. Citation ``` @article{wang2025fudokidiscreteflowbasedunified, title={FUDOKI: Discrete Flow-based Unified Understanding and Generation via Kinetic-Optimal Velocities}, author={Jin Wang and Yao Lai and Aoxue Li and Shifeng Zhang and Jiacheng Sun and Ning Kang and Chengyue Wu and Zhenguo Li and Ping Luo}, year={2025}, eprint={2505.20147}, archivePrefix={arXiv}, primaryClass={cs.CV}, url={https://arxiv.org/abs/2505.20147} } ``` ## 4. Contact **Point of Contact:** [Jin Wang](mailto:wj0529@connect.hku.hk)