Papers › NU-Wave 2: A General Neural Audio Upsampling Model for Various Sampling Rates

NU-Wave 2: A General Neural Audio Upsampling Model for Various Sampling Rates

17 Jun 2022arXiv:2206.08545archive 2025-07-28

Seungu Han, Junhyeok Lee

Conventionally, audio super-resolution models fixed the initial and the target sampling rates, which necessitate the model to be trained for each pair of sampling rates. We introduce NU-Wave 2, a diffusion model for neural audio upsampling that enables the generation of 48 kHz audio signals from inputs of various sampling rates with a single model. Based on the architecture of NU-Wave, NU-Wave 2 uses short-time Fourier convolution (STFC) to generate harmonics to resolve the main failure modes of NU-Wave, and incorporates bandwidth spectral feature transform (BSFT) to condition the bandwidths of inputs in the frequency domain. We experimentally demonstrate that NU-Wave 2 produces high-resolution audio regardless of the sampling rate of input while requiring fewer parameters than other models. The official code and the audio samples are available at https://mindslab-ai.github.io/nuwave2.

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mindslab-ai/nuwave2 officialmentioned on GitHubpytorch report
maum-ai/nuwave mentioned on GitHubpytorch report
maum-ai/nuwave2 mentioned on GitHubpytorchBSD-3-Clause report
mindslab-ai/nuwave mentioned on GitHubpytorchBSD-3-Clause report
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BSFT mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic BSD-3-Clause (permissive) · 3354a1b502b848d4 · report
Conv1d mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic BSD-3-Clause (permissive) · 2109126c17b0f297 · report
Conv2d mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic BSD-3-Clause (permissive) · f3aede0f86dce25f · report
DiffusionEmbedding mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic fingerprinted BSD-3-Clause (permissive) · daa1ce0045d6e8f9 · report
FourierUnit mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic BSD-3-Clause (permissive) · 9a9ebaea33ca45d4 · report
SpectralTransform mindslab-ai/nuwave2/model.py official repository ran · metamorphic tier: deterministic BSD-3-Clause (permissive) · 8fb6ca0db41b032a · report
FFC mindslab-ai/nuwave2/model.py official repository unverified BSD-3-Clause (permissive) · aea8c2dc5e778a5a · report
NuWave2 mindslab-ai/nuwave2/model.py official repository unverified BSD-3-Clause (permissive) · 1b16187bfba310a6 · report
ResidualBlock mindslab-ai/nuwave2/model.py official repository unverified BSD-3-Clause (permissive) · bdd9e43c2e01afe3 · report
DiffusionEmbedding maum-ai/nuwave/model.py community (archive-listed) ran · metamorphic tier: invariant fingerprinted BSD-3-Clause (permissive) · 2c33ff18a8323072 · report
NUWave rishikksh20/NU-Wave2-pytorch/model.py community (archive-listed) ran MIT (permissive) · 7ce178bec79a2b6f · report
PositionalEncoding rishikksh20/NU-Wave2-pytorch/model.py community (archive-listed) ran · metamorphic tier: invariant fingerprinted MIT (permissive) · 078a37135b02e3e5 · report
ResidualBlock maum-ai/nuwave/model.py community (archive-listed) ran · metamorphic tier: deterministic fingerprinted BSD-3-Clause (permissive) · 6f6591c01b24cb00 · report
ResidualBlock rishikksh20/NU-Wave2-pytorch/model.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · aca7a68289a844b1 · report
lognorm mindslab-ai/nuwave/lightning_model.py community (archive-listed) ran · honoured contract BSD-3-Clause (permissive) · 75b15c31859cc5da · report
silu rishikksh20/NU-Wave2-pytorch/model.py community (archive-listed) ran · honoured contract MIT (permissive) · d9caeeced554450f · report
DiffusionEmbedding rishikksh20/NU-Wave2-pytorch/model.py community (archive-listed) unverified MIT (permissive) · 816f7b789ef8c328 · report
NuWave maum-ai/nuwave/model.py community (archive-listed) unverified BSD-3-Clause (permissive) · 220987ed85906065 · report

Tasks

Audio Super-ResolutionSuper-Resolution

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ConvolutionDiffusion

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