Papers › VAEBM: A Symbiosis between Variational Autoencoders and Energy-based Models

VAEBM: A Symbiosis between Variational Autoencoders and Energy-based Models

1 Oct 2020ICLR 2021 1arXiv:2010.00654archive 2025-07-28

Zhisheng Xiao, Karsten Kreis, Jan Kautz, Arash Vahdat

Energy-based models (EBMs) have recently been successful in representing complex distributions of small images. However, sampling from them requires expensive Markov chain Monte Carlo (MCMC) iterations that mix slowly in high dimensional pixel space. Unlike EBMs, variational autoencoders (VAEs) generate samples quickly and are equipped with a latent space that enables fast traversal of the data manifold. However, VAEs tend to assign high probability density to regions in data space outside the actual data distribution and often fail at generating sharp images. In this paper, we propose VAEBM, a symbiotic composition of a VAE and an EBM that offers the best of both worlds. VAEBM captures the overall mode structure of the data distribution using a state-of-the-art VAE and it relies on its EBM component to explicitly exclude non-data-like regions from the model and refine the image samples. Moreover, the VAE component in VAEBM allows us to speed up MCMC updates by reparameterizing them in the VAE's latent space. Our experimental results show that VAEBM outperforms state-of-the-art VAEs and EBMs in generative quality on several benchmark image datasets by a large margin. It can generate high-quality images as large as 256×256 pixels with short MCMC chains. We also demonstrate that VAEBM provides complete mode coverage and performs well in out-of-distribution detection. The source code is available at https://github.com/NVlabs/VAEBM

PaperPDFConference PDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2010.00654")

Code

Syntology Ran 6 of 9 code samples harvested from 1 repository linked to this paper; 3 have no recorded run. Of those that ran: 1 ran · honoured contract; 1 ran · our draft was wrong; 2 ran · fixture could not drive it; 2 ran with no contract checked.

By repository: official repository: 7 samples from 1 repository, 5 ran; 2 identical to code first harvested elsewhere. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

NVlabs/VAEBM officialmentioned in papermentioned on GitHubpytorch report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

9 samples harvested; 6 ran; 1 honoured the contract we drafted; 3 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

1ran · honoured contract
1ran · our draft was wrong
2ran · fixture could not drive it
2ran
3unverified

Licence: 9 of the 9 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from NVlabs/VAEBM. Some samples are identical code Syntology first harvested from another repository; for those, this paper's copy is not located and its licence is not recorded. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

Conv2D NVlabs/VAEBM/ebm_models.py official repository ran · metamorphic tier: deterministic licence not identified · pointer only · 7278a7b671e05581 · report
Lip_swish NVlabs/VAEBM/ebm_models.py official repository ran · honoured contract fingerprinted licence not identified · pointer only · 8f49ee66eb82532f · report
ResBlock NVlabs/VAEBM/ebm_models.py official repository ran · metamorphic tier: deterministic licence not identified · pointer only · f9563e26a42cd214 · report
norm NVlabs/VAEBM/ebm_models.py official repository ran · our draft was wrong fingerprinted licence not identified · pointer only · e68ef3509ca0d2e9 · report
sample_buffer NVlabs/VAEBM/train_VAEBM.py official repository ran · fixture could not drive it licence not identified · pointer only · f3e2ca7ba6ae5e28 · report
EBM_CelebA64 NVlabs/VAEBM/ebm_models.py official repository unverified licence not identified · pointer only · 66595f170e26d4b9 · report
sample_from_EBM NVlabs/VAEBM/sample_VAEBM.py official repository unverified licence not identified · pointer only · 18cf305569971c49 · report
normalize_weight_jit identical code first harvested elsewhere ran · fixture could not drive it licence of this copy not recorded · 509ea43acade44e9 · report
average_tensor identical code first harvested elsewhere unverified licence of this copy not recorded · dd83a8a0b04c47fd · report

Tasks

Image GenerationOut-of-Distribution Detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Generation CelebA-HQ 256x256 VAEBM FID 20.38 #16 of 19 Archive leaderboard report
Image Generation CelebA-HQ 64x64 VAEBM FID 5.31 #2 of 3 Archive leaderboard report
Image Generation Stacked MNIST VAEBM FID 12.96 #1 of 3 Archive leaderboard report
Image Generation Stacked MNIST VAEBM Inception score 8.15 #1 of 3 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

EBM

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections