RETURNN

by RWTH Aachen

RWTH's flexible neural network training framework for ASR research.

TL;DR

RWTH's flexible neural network training framework for ASR research.

Best for academic groups running highly customized E2E ASR experiments. Pricing: free.

Category
Open source
License
—
Stars
—
Last push
—
Pricing
free
Platforms
Linux

What it is

The RWTH Extensible Training Framework for RNNs. RWTHs' speech group ships their CSR systems here. RETURNN public license (MIT-style).

Best for: Academic groups running highly customized E2E ASR experiments.
Watch out for: Steep learning curve; config-file-driven; small community.

Install / use

pip install returnn

Features

Speaker diarizationNo
Word-level timestampsYes
Streaming / real-timeNo
Languages supported20
HIPAA eligibleNo

RETURNN vs Whipscribe

FeatureRETURNNWhipscribe
CategoryOpen sourceTranscription APIs
Pricingfreefree beta
Speaker diarizationNoYes
Word timestampsYesYes
StreamingNoNo
Languages2099
PlatformsLinuxWeb, API, MCP

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