Deepgram
Speech-to-text service implementation using Deepgram’s real-time transcription API
Overview
DeepgramSTTService
provides real-time speech-to-text capabilities using Deepgram’s WebSocket API. It supports interim results, language detection, and voice activity detection (VAD).
Installation
To use DeepgramSTTService
, install the required dependencies:
You’ll also need to set up your Deepgram API key as an environment variable: DEEPGRAM_API_KEY
.
You can obtain a Deepgram API key by signing up at Deepgram.
Configuration
Constructor Parameters
Your Deepgram API key
Custom Deepgram API endpoint URL
Custom transcription options
Default Options
Input
The service processes InputAudioRawFrame
instances containing:
- Raw PCM audio data
- 16-bit depth
- 16kHz sample rate
- Single channel (mono)
Output Frames
TranscriptionFrame
Generated for final transcriptions, containing:
Transcribed text
User identifier
ISO 8601 formatted timestamp
Detected language (if available)
InterimTranscriptionFrame
Generated during ongoing speech, containing same fields as TranscriptionFrame but with preliminary results.
Methods
See the STT base class methods for additional functionality.
Language Setting
Model Selection
Usage Example
Language Support
Deepgram STT supports the following languages and regional variants:
Language Code | Description | Service Codes |
---|---|---|
Language.BG | Bulgarian | bg |
Language.CA | Catalan | ca |
Language.ZH | Chinese (Mandarin, Simplified) | zh , zh-CN , zh-Hans |
Language.ZH_TW | Chinese (Mandarin, Traditional) | zh-TW , zh-Hant |
Language.ZH_HK | Chinese (Cantonese, Traditional) | zh-HK |
Language.CS | Czech | cs |
Language.DA | Danish | da , da-DK |
Language.NL | Dutch | nl |
Language.NL_BE | Dutch (Flemish) | nl-BE |
Language.EN | English | en |
Language.EN_US | English (US) | en-US |
Language.EN_AU | English (Australia) | en-AU |
Language.EN_GB | English (UK) | en-GB |
Language.EN_NZ | English (New Zealand) | en-NZ |
Language.EN_IN | English (India) | en-IN |
Language.ET | Estonian | et |
Language.FI | Finnish | fi |
Language.FR | French | fr |
Language.FR_CA | French (Canada) | fr-CA |
Language.DE | German | de |
Language.DE_CH | German (Switzerland) | de-CH |
Language.EL | Greek | el |
Language.HI | Hindi | hi |
Language.HU | Hungarian | hu |
Language.ID | Indonesian | id |
Language.IT | Italian | it |
Language.JA | Japanese | ja |
Language.KO | Korean | ko , ko-KR |
Language.LV | Latvian | lv |
Language.LT | Lithuanian | lt |
Language.MS | Malay | ms |
Language.NO | Norwegian | no |
Language.PL | Polish | pl |
Language.PT | Portuguese | pt |
Language.PT_BR | Portuguese (Brazil) | pt-BR |
Language.PT_PT | Portuguese (Portugal) | pt-PT |
Language.RO | Romanian | ro |
Language.RU | Russian | ru |
Language.SK | Slovak | sk |
Language.ES | Spanish | es , es-419 |
Language.SV | Swedish | sv , sv-SE |
Language.TH | Thai | th , th-TH |
Language.TR | Turkish | tr |
Language.UK | Ukrainian | uk |
Language.VI | Vietnamese | vi |
Special Features
- Supports multilingual transcription (Spanish + English) using
multi
- Provides multiple regional variants for major languages
- Supports traditional and simplified Chinese scripts
Usage Example
Note: Language support may vary by model. Check Deepgram’s documentation for model-specific language availability.
Frame Flow
Metrics Support
The service supports metrics collection when VAD is enabled:
- Time to First Byte (TTFB)
- Processing duration
- Speech detection events
Notes
- Requires valid Deepgram API key
- Supports real-time transcription
- Handles WebSocket connection management
- Provides language detection
- Supports model switching
- Includes VAD capabilities
- Manages connection lifecycle