Speech recognition usually fails for languages with very little transcribed audio. This makes voice-based tools unavailable to many speakers.
The researchers compared several model types on low-resource African languages. One model processes both speech and text, another focuses on speech only, and a third works across many languages. They studied how much audio is needed, joint training, and domain-specific data.
The speech-and-text model had the fewest character errors. Each model needed different amounts of audio: one peaked at about 150 hours, another kept improving up to 300 hours. Using a model trained on a related language helped. These results guide data collection for low-resource speech tools.
