1 Speech recognition on read speech
What it measures
Lower is better. The share of words a system writes wrong, with the share of characters wrong in brackets. Every system is scored after the same Tamil-aware cleanup of the text. FLEURS and Kathbath are public test sets of people reading sentences aloud. Kathbath’s new speakers are people missing from its training data.
| System | Type | FLEURS | Kathbath, known speakers | Kathbath, new speakers |
|---|---|---|---|---|
| Indic-Transcribe core | Open weights | 26.1% (12.1%) | 21.5% (3.5%) | 23.4% (4.1%) |
| IndicConformer 600M | Open weights | 27.1% (11.1%) | 21.5% (3.4%) | 23.4% (4.0%) |
| Whisper large-v3 turbo | Open weights | 67.5% (18.5%) | 67.5% (15.9%) | 67.2% (16.0%) |
| MiniCPM-o 4.5 | Open weights | 140.0% (103.1%) | not run | not run |
How to read it
One wrong letter makes a whole Tamil word wrong, so word error rates run much higher than character error rates. Read speech is the easy case. Phone audio, background noise and regional speech come next.
Kathbath is home ground for the two Tamil systems. AI4Bharat made Kathbath, and both systems come from AI4Bharat or its partners, so they may have trained on Kathbath’s training half. The two tie on Kathbath, though they agree word for word on only 30% of clips.
One system isn’t built for Tamil
MiniCPM-o 4.5 is a general voice model with no Tamil speech training. A score over 100% means it wrote more wrong words than the clip has.
Source
Uraikal track A1. Whisper was transcribed with transcribe.py, the others with their own published code.