Papers › SlimFlow: Training Smaller One-Step Diffusion Models with Rectified Flow

SlimFlow: Training Smaller One-Step Diffusion Models with Rectified Flow

17 Jul 2024arXiv:2407.12718archive 2025-07-28

Yuanzhi Zhu, Xingchao Liu, Qiang Liu

Diffusion models excel in high-quality generation but suffer from slow inference due to iterative sampling. While recent methods have successfully transformed diffusion models into one-step generators, they neglect model size reduction, limiting their applicability in compute-constrained scenarios. This paper aims to develop small, efficient one-step diffusion models based on the powerful rectified flow framework, by exploring joint compression of inference steps and model size. The rectified flow framework trains one-step generative models using two operations, reflow and distillation. Compared with the original framework, squeezing the model size brings two new challenges: (1) the initialization mismatch between large teachers and small students during reflow; (2) the underperformance of naive distillation on small student models. To overcome these issues, we propose Annealing Reflow and Flow-Guided Distillation, which together comprise our SlimFlow framework. With our novel framework, we train a one-step diffusion model with an FID of 5.02 and 15.7M parameters, outperforming the previous state-of-the-art one-step diffusion model (FID=6.47, 19.4M parameters) on CIFAR10. On ImageNet 64×64 and FFHQ 64×64, our method yields small one-step diffusion models that are comparable to larger models, showcasing the effectiveness of our method in creating compact, efficient one-step diffusion models.

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variance_scaling yuanzhi-zhu/SlimFlow/models/layers.py official repository ran no licence file found · pointer only · 3ac11bfe0ae80195 · report
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get_weight yuanzhi-zhu/SlimFlow/models/up_or_down_sampling.py official repository unverified no licence file found · pointer only · 8db300b9f1afb2d3 · report
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naive_upsample_2d yuanzhi-zhu/SlimFlow/models/up_or_down_sampling.py official repository unverified no licence file found · pointer only · f425357463a3de36 · report
ncsn_conv1x1 yuanzhi-zhu/SlimFlow/models/layers.py official repository unverified no licence file found · pointer only · 85b2235eb7afaa4f · report

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