Verbatim Transcription
Native-listener labels delivered to a versioned speech style guide.
Audio & Speech Annotation Services for Voice AI and ASR
Transcription, speaker diarization, timing, emotion, acoustic events and phonetic labeling across 30+ global languages, with comprehensive Indian regional-language coverage.
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What Is Audio & Speech Annotation?
Audio annotation turns recorded sound into machine-readable data: what was said, who said it, when they said it, how they said it and what else was audible.
Audio Data Collection creates the recording; Text & NLP Annotation adds meaning after transcription.
Audio & Speech Annotation Types We Deliver
Clean and Normalised Transcription
Native-listener labels delivered to a versioned speech style guide.
Timestamping and Segmentation
Native-listener labels delivered to a versioned speech style guide.
Forced Alignment
Native-listener labels delivered to a versioned speech style guide.
Speaker Diarization
Native-listener labels delivered to a versioned speech style guide.
Speaker Identification and Voice Matching
Native-listener labels delivered to a versioned speech style guide.
Language and Dialect Identification
Native-listener labels delivered to a versioned speech style guide.
Emotion and Tone Labeling
Native-listener labels delivered to a versioned speech style guide.
Acoustic Event Classification
Native-listener labels delivered to a versioned speech style guide.
Phonetic Transcription
Native-listener labels delivered to a versioned speech style guide.
Wake Word and Keyword Spotting
Native-listener labels delivered to a versioned speech style guide.
Voice Intent and Slot Labeling
Native-listener labels delivered to a versioned speech style guide.
Audio Quality Rating
Native-listener labels delivered to a versioned speech style guide.
TTS Data QC and Prosody Review
Native-listener labels delivered to a versioned speech style guide.
Choose Verbatim or Clean Before Annotation Starts
Verbatim preserves fillers, false starts, repetitions and stutters for ASR. Clean transcription normalises spoken language for search, subtitles and readable archives.
Our Audio Annotation Process
- Sample and use-case review
- Style guide and schema
- Native-listener calibration
- Pilot and error analysis
- Production annotation
- Listening QA and adjudication
- Secure delivery and iteration
Speech Annotation Quality You Can Measure
Raw and normalised word error rate, character error rate, diarization error rate, timestamp tolerance, speaker consistency, blind gold clips and second-pass listening review.
Global Language Coverage with India's Regional Depth
We support 30+ global languages across European, Asian and Middle Eastern markets. Our specialist advantage is comprehensive coverage across India's regional languages, accents, dialects and code-switched speech.
Formats, Audio Handling and Use Cases
JSON, JSONL, RTTM, CTM, TextGrid, SRT, VTT, Kaldi, Hugging Face, ELAN EAF, CSV, TSV and custom schemas for ASR, call analytics, TTS, healthcare, acoustic events and accessibility.
ASR Assistance, Voice Security and Cost
Machine transcription is used only where it improves throughput and every assisted batch receives listening review. Voice data uses controlled access, audit trails, PII controls and contract-defined retention.
Real-time ratio planning ranges
Clean single-speaker audio is commonly 2 to 4 times real time; structured multi-speaker audio 4 to 8 times; difficult overlap, accents and word timing may exceed 10 times. A pilot confirms the actual ratio.
Related Services and Proof
Video Annotation Data Cleaning & Validation Audio samples Case studies
Frequently Asked Questions About Audio & Speech Annotation
What is audio annotation?
Audio annotation turns recorded sound into structured data: what was said, who said it, when and how they said it, and which non-speech sounds were present.
What is the difference between verbatim and clean transcription?
Verbatim preserves fillers, false starts and stutters. Clean transcription removes disfluencies and normalises numbers and dates.
What is speaker diarization?
Speaker diarization determines who spoke when and maintains consistent speaker identities through overlap and interruption.
How do you measure speech annotation quality?
We report WER, DER, timestamp accuracy, speaker consistency, style-guide conformance, hidden gold clips and second-pass listening review.
Do you handle Indian regional languages, accents and code-switched speech?
Yes. Alongside global-language delivery, our India-wide coverage includes regional languages, regional Indian English, dialects, mixed-language speech, register and lower-resource varieties.
Which languages do you support?
We support 30+ global languages, with comprehensive coverage across India's regional languages, accents, dialects and code-switched speech.
How do we start?
Share 30 to 60 minutes of representative difficult audio and your style requirements for a measured pilot and throughput estimate.