Papers › Pseudo Numerical Methods for Diffusion Models on Manifolds

Pseudo Numerical Methods for Diffusion Models on Manifolds

20 Feb 2022ICLR 2022 4arXiv:2202.09778archive 2025-07-28

Luping Liu, Yi Ren, Zhijie Lin, Zhou Zhao

Denoising Diffusion Probabilistic Models (DDPMs) can generate high-quality samples such as image and audio samples. However, DDPMs require hundreds to thousands of iterations to produce final samples. Several prior works have successfully accelerated DDPMs through adjusting the variance schedule (e.g., Improved Denoising Diffusion Probabilistic Models) or the denoising equation (e.g., Denoising Diffusion Implicit Models (DDIMs)). However, these acceleration methods cannot maintain the quality of samples and even introduce new noise at a high speedup rate, which limit their practicability. To accelerate the inference process while keeping the sample quality, we provide a fresh perspective that DDPMs should be treated as solving differential equations on manifolds. Under such a perspective, we propose pseudo numerical methods for diffusion models (PNDMs). Specifically, we figure out how to solve differential equations on manifolds and show that DDIMs are simple cases of pseudo numerical methods. We change several classical numerical methods to corresponding pseudo numerical methods and find that the pseudo linear multi-step method is the best in most situations. According to our experiments, by directly using pre-trained models on Cifar10, CelebA and LSUN, PNDMs can generate higher quality synthetic images with only 50 steps compared with 1000-step DDIMs (20x speedup), significantly outperform DDIMs with 250 steps (by around 0.4 in FID) and have good generalization on different variance schedules. Our implementation is available at https://github.com/luping-liu/PNDM.

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luping-liu/PNDM officialmentioned in paperpytorch report
HE-diffusion/HE-diffusion mentioned on GitHubpytorch report
MoonInTheRiver/DiffSinger mentioned on GitHubpytorchMIT report
compvis/latent-diffusion mentioned on GitHubpytorch report
hankpipi/diffusers-hetu mentioned on GitHubjaxApache-2.0 report
sanster/lama-cleaner mentioned on GitHubpytorch report
voletiv/mcvd-pytorch mentioned on GitHubpytorch report

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gen_fon luping-liu/pndm/runner/method.py official repository ran · our draft was wrong Apache-2.0 (permissive) · 5d6a41979ad9dba0 · report
gen_pflow luping-liu/pndm/runner/method.py official repository ran · our draft was wrong Apache-2.0 (permissive) · 57784a3c771692c1 · report
choose_method luping-liu/pndm/runner/method.py official repository unverified Apache-2.0 (permissive) · 1f1b0f6af624ca13 · report
DPM_Solver sanster/lama-cleaner/iopaint/model/anytext/ldm/models/diffusion/dpm_solver/dpm_solver.py community (archive-listed) ran Apache-2.0 (permissive) · cf5e8fc69bc54a1f · report
DiffusionModel MaximeVandegar/Papers-in-100-Lines-of-Code/Pseudo_Numerical_Methods_for_Diffusion_Models_on_Manifolds/pndms_solver.py community (archive-listed) ran MIT (permissive) · 293ed430e4577434 · report
LogSNRLinearSchedule beresandras/clear-diffusion-keras/schedule.py community (archive-listed) ran fingerprinted MIT (permissive) · 571c79128001a43c · report
PLMSSampler compvis/latent-diffusion/ldm/models/diffusion/plms.py community (archive-listed) ran MIT (permissive) · 137e9fde705fd937 · report
expand_dims sanster/lama-cleaner/iopaint/model/anytext/ldm/models/diffusion/dpm_solver/dpm_solver.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 5bda79d6c0eb0ae5 · report
runge_kutta voletiv/mcvd-pytorch/models/pndm.py community (archive-listed) ran · our draft was wrong MIT (permissive) · 94bdd2bdf9c3365b · report
transfer voletiv/mcvd-pytorch/models/pndm.py community (archive-listed) ran · our draft was wrong fingerprinted MIT (permissive) · bdf5cc5a197a1452 · report
DPM_Solver HE-diffusion/HE-diffusion/ldm/models/diffusion/dpm_solver/dpm_solver.py community (archive-listed) unverified licence not identified · pointer only · 11702d4c33a21359 · report
DiffusionSchedule beresandras/clear-diffusion-keras/schedule.py community (archive-listed) unverified MIT (permissive) · 180c5f8fe02d887b · report
gen_order_4 voletiv/mcvd-pytorch/models/pndm.py community (archive-listed) unverified MIT (permissive) · 27d28515afaee042 · report
expand_dims identical code first harvested elsewhere ran · our draft was wrong licence of this copy not recorded · e6110366588c5c65 · report

Tasks

DenoisingImage Generation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Generation CelebA 64x64 PNDM FID 2.71 #16 of 39 Archive leaderboard report
Image Generation LSUN Bedroom 256 x 256 PNDM FID 5.68 #13 of 32 Archive leaderboard report
Image Generation LSUN Churches 256 x 256 PNDM FID 8.69 #23 of 27 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

Diffusion

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