Real-Time Streaming Mel Vocoding with Generative Flow Matching
Abstract
The task of Mel vocoding, i.e., the inversion of a Mel magnitude spectrogram to an audio waveform, is still a key component in many text-to-speech (TTS) systems today. Based on generative flow matching, our prior work on generative STFT phase retrieval (DiffPhase), and the pseudoinverse operator of the Mel filterbank, we develop MelFlow, a streaming-capable generative Mel vocoder for speech sampled at 16 kHz with an algorithmic latency of only 32 ms and a total latency of 48 ms. We show real-time streaming capability at this latency not only in theory, but in practice on a consumer laptop GPU. Furthermore, we show that our model achieves substantially better PESQ and SI-SDR values compared to well-established not streaming-capable baselines for Mel vocoding including HiFi-GAN.
Cite
@article{arxiv.2509.15085,
title = {Real-Time Streaming Mel Vocoding with Generative Flow Matching},
author = {Simon Welker and Tal Peer and Timo Gerkmann},
journal= {arXiv preprint arXiv:2509.15085},
year = {2025}
}
Comments
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