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arXiv · 2505.13447

Mean Flows for One-step Generative Modeling

Zhengyang Geng·Mingyang Deng·Xingjian Bai·J. Zico Kolter·Kaiming He
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Abstract

We propose a principled and effective framework for one-step generative modeling. We introduce the notion of average velocity to characterize flow fields, in contrast to instantaneous velocity modeled by Flow Matching methods. A well-defined identity between average and instantaneous velocities is derived and used to guide neural network training. Our method, termed the MeanFlow model, is self-contained and requires no pre-training, distillation, or curriculum learning. MeanFlow demonstrates strong empirical performance: it achieves an FID of 3.43 with a single function evaluation (1-NFE) on ImageNet 256x256 trained from scratch, significantly outperforming previous state-of-the-art one-step diffusion/flow models. Our study substantially narrows the gap between one-step diffusion/flow models and their multi-step predecessors, and we hope it will motivate future research to revisit the foundations of these powerful models.

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Zhengyang Geng, Mingyang Deng, Xingjian Bai, J. Zico Kolter, Kaiming He. 2025-05-19. Mean Flows for One-step Generative Modeling. https://arxiv.org/abs/2505.13447

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