Papers › WaveFlow: A Compact Flow-based Model for Raw Audio

WaveFlow: A Compact Flow-based Model for Raw Audio

3 Dec 2019ICML 2020 1arXiv:1912.01219archive 2025-07-28

Wei Ping, Kainan Peng, Kexin Zhao, Zhao Song

In this work, we propose WaveFlow, a small-footprint generative flow for raw audio, which is directly trained with maximum likelihood. It handles the long-range structure of 1-D waveform with a dilated 2-D convolutional architecture, while modeling the local variations using expressive autoregressive functions. WaveFlow provides a unified view of likelihood-based models for 1-D data, including WaveNet and WaveGlow as special cases. It generates high-fidelity speech as WaveNet, while synthesizing several orders of magnitude faster as it only requires a few sequential steps to generate very long waveforms with hundreds of thousands of time-steps. Furthermore, it can significantly reduce the likelihood gap that has existed between autoregressive models and flow-based models for efficient synthesis. Finally, our small-footprint WaveFlow has only 5.91M parameters, which is 15× smaller than WaveGlow. It can generate 22.05 kHz high-fidelity audio 42.6× faster than real-time (at a rate of 939.3 kHz) on a V100 GPU without engineered inference kernels.

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Code

Syntology Ran 3 of 9 code samples harvested from 1 repository linked to this paper; 6 have no recorded run. Of those that ran: 1 ran · honoured contract; 2 ran · our draft was wrong.

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PaddlePaddle/Parakeet officialmentioned in papermentioned on GitHubpaddleNOASSERTION report
L0SG/NanoFlow mentioned on GitHubpytorch report
L0SG/WaveFlow mentioned on GitHubpytorchBSD-3-Clause report
caillonantoine/waveflow mentioned on GitHubpytorch report

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9 samples harvested; 3 ran; 1 honoured the contract we drafted; 6 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
2ran · our draft was wrong
6unverified

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dynamic_range_compression L0SG/WaveFlow/tacotron2_custom/audio_processing.py community (archive-listed) ran · our draft was wrong fingerprinted BSD-3-Clause (permissive) · 83e2c862f7374ac7 · report
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griffin_lim L0SG/WaveFlow/tacotron2_custom/audio_processing.py community (archive-listed) ran · our draft was wrong BSD-3-Clause (permissive) · 9f9ec26d4cdfdf7d · report
bipartize L0SG/WaveFlow/functions.py community (archive-listed) unverified BSD-3-Clause (permissive) · 21e38cc8239d26e5 · report
files_to_list L0SG/WaveFlow/mel2samp.py community (archive-listed) unverified BSD-3-Clause (permissive) · 6e8184ff4faf3139 · report
fused_add_tanh_sigmoid_multiply L0SG/WaveFlow/modules.py community (archive-listed) unverified BSD-3-Clause (permissive) · 4537862a4c53b4c3 · report
fused_res_skip L0SG/WaveFlow/modules.py community (archive-listed) unverified BSD-3-Clause (permissive) · 504a64a95e4d96d6 · report
gaussian_log_p L0SG/WaveFlow/functions.py community (archive-listed) unverified BSD-3-Clause (permissive) · 054f22912d47c960 · report
load_wav_to_torch L0SG/WaveFlow/mel2samp.py community (archive-listed) unverified BSD-3-Clause (permissive) · 50d1245d6b4055c4 · report

Tasks

Speech Synthesis

1 archive task tag without a task page not shown.

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Speech Synthesis LibriTTS WaveFlow M-STFT 1.1120 #13 of 15 Archive leaderboard report
Speech Synthesis LibriTTS WaveFlow MCD 1.2455 #13 of 15 Archive leaderboard report
Speech Synthesis LibriTTS WaveFlow PESQ 3.027 #13 of 15 Archive leaderboard report
Speech Synthesis LibriTTS WaveFlow Periodicity 0.1416 #13 of 15 Archive leaderboard report
Speech Synthesis LibriTTS WaveFlow V/UV F1 0.9410 #13 of 15 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

Affine CouplingDilated Causal ConvolutionInvertible 1x1 ConvolutionMixture of Logistic DistributionsNormalizing FlowsWaveGlowWaveNet

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