ASR datasets · தமிழ்
Tamil ASR Training Data
Transcribed speech corpora built to train and evaluate automatic speech recognition, with verbatim transcription, timestamps and per-token language tagging where code-mixing occurs. This page covers how that works specifically for Tamil, where extreme diglossia: written tamil and spoken tamil differ so much that read-speech corpora are near-useless for conversational asr.
- Language
- Tamil (ta-IN)
- Dialects covered
- 6
- Typical programme
- 500-2,000 hours
- Cities
- Chennai, Coimbatore, Madurai
What changes when the language is Tamil
The service specification stays constant across languages; the linguistics do not. For Tamil, three things drive the design of a asr datasets programme.
- Extreme diglossia: written Tamil and spoken Tamil differ so much that read-speech corpora are near-useless for conversational ASR
- Dialect spread: Chennai (Madras Bashai), Kongu (Coimbatore), Madurai, Nellai (Tirunelveli)
- Tanglish is the default urban register. Technology, finance, and workplace vocabulary is largely English embedded in Tamil syntax.
Technical specification
| Parameter | Standard |
|---|---|
| Audio | 16 kHz or 48 kHz PCM WAV |
| Transcription | Verbatim, including disfluencies, false starts and fillers |
| Timestamps | Utterance level by default; word level on request |
| Tagging | Noise, overlap, unintelligible, foreign-language and code-switch tags |
| Normalisation | Raw and normalised text columns delivered separately |
| Split | Train/dev/test splits with no speaker leakage across splits |
Tamil cohort design
Recruit by district rather than by city alone; Chennai-only cohorts produce models that degrade sharply in the south and west of the state.
| Dimension | Typical split | Why it matters for Tamil |
|---|---|---|
| Gender | 50 / 50 | Pitch range differences change acoustic model behaviour; unbalanced cohorts bias recognition |
| Age | 18-25: 30%, 26-40: 40%, 41-60: 30% | Older speakers retain conservative Tamil forms that younger urban speakers have lost |
| Region | Tamil Nadu / Puducherry / parts of Karnataka and Kerala and others | Dialect spread across 6 recognised varieties |
| Education | Mixed, including below-graduate | Prompt-reading fluency correlates with education and skews prosody |
| Condition | Studio / quiet room / field | Match the noise profile of your deployment |
Process
- Style guide authored per language, covering numerals, loanwords, script and disfluency rules
- Transcriber calibration round with inter-annotator agreement measurement
- First-pass transcription
- Second-pass native review
- Automated consistency checks against the style guide
- Split generation with speaker-disjoint partitions
Tamil-specific quality rules
- Transcribers normalising spoken Tamil into literary Tamil, destroying the acoustic-text alignment
- ழ / ள / ல confusion
- Inconsistent handling of English insertions: Tamil script transliteration vs Latin script must be fixed in the guide
Agreement is measured, not assumed. We report word-level agreement on a held-out sample so you can judge label quality before training on it.
Deliverables
- Audio plus aligned transcripts (JSON/TSV, or your schema)
- Style guide as delivered documentation
- Inter-annotator agreement report
- Speaker-disjoint train/dev/test splits
Worked example
A representative Tamil asr datasets engagement: 500 hours from 1,000 speakers, 50/50 gender, ages 18-45, spread across Chennai, Coimbatore, Madurai, recorded to the specification above and delivered in WAV with a per-utterance manifest.
Timeline: Transcription adds roughly 1-2 weeks per 100 hours after recording, per language.
Where this data is missing today
Almost all public Tamil audio is literary read speech from news or scripture. Genuine colloquial Tamil, especially southern and Kongu varieties, is the single biggest gap for anyone building Tamil voice products.
Frequently asked
How much does Tamil asr datasets cost?
Priced per delivered hour or unit against a written spec. The cost drivers for Tamil are dialect spread, demographic narrowness and recording condition, in that order.
Which Tamil dialects are included?
By default Chennai (Madras Bashai), Kongu (Coimbatore), Madurai, Nellai (Tirunelveli) and others, tagged per speaker. You can also commission a single-dialect corpus if you are targeting one region.
Can you deliver Tamil data in our format?
Yes. Audio plus aligned transcripts (JSON/TSV, or your schema) is the default, but naming, schema and directory structure follow your pipeline.
How long does a Tamil programme take?
Transcription adds roughly 1-2 weeks per 100 hours after recording, per language.
Request a Tamil asr datasets quote
Hours, speakers, dialects, deadline. Send what you have.