Papers › PFDiff: Training-free Acceleration of Diffusion Models through the Gradient Guidance...

PFDiff: Training-free Acceleration of Diffusion Models through the Gradient Guidance of Past and Future

16 Aug 2024arXiv:2408.08822archive 2025-07-28

Guangyi Wang, Yuren Cai, Lijiang Li, Wei Peng, Songzhi Su

Diffusion Probabilistic Models (DPMs) have shown remarkable potential in image generation, but their sampling efficiency is hindered by the need for numerous denoising steps. Most existing solutions accelerate the sampling process by proposing fast ODE solvers. However, the inevitable discretization errors of the ODE solvers are significantly magnified when the number of function evaluations (NFE) is fewer. In this work, we propose PFDiff, a novel training-free and orthogonal timestep-skipping strategy, which enables existing fast ODE solvers to operate with fewer NFE. Specifically, PFDiff initially utilizes gradient replacement from past time steps to predict a "springboard". Subsequently, it employs this "springboard" along with foresight updates inspired by Nesterov momentum to rapidly update current intermediate states. This approach effectively reduces unnecessary NFE while correcting for discretization errors inherent in first-order ODE solvers. Experimental results demonstrate that PFDiff exhibits flexible applicability across various pre-trained DPMs, particularly excelling in conditional DPMs and surpassing previous state-of-the-art training-free methods. For instance, using DDIM as a baseline, we achieved 16.46 FID (4 NFE) compared to 138.81 FID with DDIM on ImageNet 64x64 with classifier guidance, and 13.06 FID (10 NFE) on Stable Diffusion with 7.5 guidance scale.

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onefly123/PFDiff officialmentioned on GitHubpytorchMIT report

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2ran · honoured contract
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interpolate_fn onefly123/PFDiff/uncondition/dpm-solver/PFDiff_1.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · 6a35b62fbc80f70a · report
betas_for_alpha_bar onefly123/PFDiff/condition/guided_diffusion/guided_diffusion/PFDiff_1.py official repository ran · honoured contract MIT (permissive) · 2ab2316ac6fdd869 · report
expand_dims onefly123/PFDiff/uncondition/dpm-solver/PFDiff_1.py official repository ran · our draft was wrong MIT (permissive) · e6110366588c5c65 · report
generalized_steps onefly123/pfdiff/uncondition/ddim-main/functions/denoising_PFDiff_1.py official repository ran · our draft was wrong MIT (permissive) · 401988a4df7d964c · report
get_named_beta_schedule onefly123/PFDiff/condition/guided_diffusion/guided_diffusion/PFDiff_1.py official repository ran · honoured contract MIT (permissive) · a086d6286a40b889 · report
model_wrapper onefly123/pfdiff/uncondition/dpm-solver/PFDiff_1.py official repository ran · fixture could not drive it MIT (permissive) · 3fbe2edeed05f669 · report
model_wrapper onefly123/PFDiff/uncondition/dpm-solver/PFDiff_1.py official repository ran · fixture could not drive it MIT (permissive) · 0e68c8747f1cfcd9 · report
interpolate_fn identical code first harvested elsewhere ran · our draft was wrong fingerprinted licence of this copy not recorded · 39c68b6295eaca2f · report
expand_dims identical code first harvested elsewhere unverified licence of this copy not recorded · 292d0a3a80570d32 · report

Tasks

DenoisingImage Generation

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Methods

DiffusionSGD

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