Papers › NVAE: A Deep Hierarchical Variational Autoencoder

NVAE: A Deep Hierarchical Variational Autoencoder

8 Jul 2020NeurIPS 2020 12arXiv:2007.03898archive 2025-07-28

Arash Vahdat, Jan Kautz

Normalizing flows, autoregressive models, variational autoencoders (VAEs), and deep energy-based models are among competing likelihood-based frameworks for deep generative learning. Among them, VAEs have the advantage of fast and tractable sampling and easy-to-access encoding networks. However, they are currently outperformed by other models such as normalizing flows and autoregressive models. While the majority of the research in VAEs is focused on the statistical challenges, we explore the orthogonal direction of carefully designing neural architectures for hierarchical VAEs. We propose Nouveau VAE (NVAE), a deep hierarchical VAE built for image generation using depth-wise separable convolutions and batch normalization. NVAE is equipped with a residual parameterization of Normal distributions and its training is stabilized by spectral regularization. We show that NVAE achieves state-of-the-art results among non-autoregressive likelihood-based models on the MNIST, CIFAR-10, CelebA 64, and CelebA HQ datasets and it provides a strong baseline on FFHQ. For example, on CIFAR-10, NVAE pushes the state-of-the-art from 2.98 to 2.91 bits per dimension, and it produces high-quality images on CelebA HQ. To the best of our knowledge, NVAE is the first successful VAE applied to natural images as large as 256×256 pixels. The source code is available at https://github.com/NVlabs/NVAE .

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NVlabs/NVAE officialmentioned in papermentioned on GitHubpytorch report
Aiwizo/template-nvae mentioned on GitHubpytorch report
NVlabs/LSGM mentioned on GitHubpytorch report
NVlabs/VAEBM mentioned on GitHubpytorch report
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Tasks

Image Generation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Generation CIFAR-10 NVAE w/ flow FID 32.53 #70 of 78 Archive leaderboard report
Image Generation CelebA 256x256 NVAE w/ flow bpd 0.70 #5 of 17 Archive leaderboard report
Image Generation FFHQ 256 x 256 NVAE w/ flow bits/dimension 0.69 #51 of 51 Archive leaderboard report
Image Generation ImageNet 32x32 NVAE w/ flow bpd 3.92 #29 of 35 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

Introduced by this paper: NVAE Encoder Residual Cell, NVAE Generative Residual Cell, Residual Normal Distribution

1x1 ConvolutionAdaMaxAverage PoolingBatch NormalizationConvolutionCosine AnnealingDense ConnectionsDepthwise ConvolutionDepthwise Separable ConvolutionHierarchical VAENVAENVAE Encoder Residual CellNVAE Generative Residual CellNormalizing FlowsPointwise ConvolutionReLUResidual ConnectionResidual Normal DistributionSigmoid ActivationSpectral NormalizationSqueeze-and-Excitation BlockWeight Normalization

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