Custom STT service - Omi Developers

You can point the Omi phone app at your own real-time transcription service (Settings → Developer Settings → Transcription → Custom). The app streams audio straight to your service, shows the segments you return, and forwards them to the Omi backend as suggested transcripts.

What your service receives

Message	Format	Meaning
Audio frames	Binary	Raw PCM: signed 16-bit little-endian, mono, no WAV header. The sample rate matches the device (16 kHz on current hardware). The app decodes Opus before sending, so your service never receives Opus packets.
`{"type": "CloseStream"}`	JSON	The audio stream has ended

What your service sends

A JSON object with a segments array:

{
  "segments": [
    { "text": "Hello, how are you?", "speaker": "SPEAKER_00", "start": 0.0, "end": 1.5 },
    { "text": "I'm doing great, thanks!", "speaker": "SPEAKER_01", "start": 1.6, "end": 3.2 }
  ]
}

Field	Type	Required	Meaning
`text`	string	Yes	Transcribed text
`speaker`	string	No	Speaker label, such as `SPEAKER_00`
`start`	float	No	Start time in seconds
`end`	float	No	End time in seconds

Send an object with a segments key. A bare array is rejected.
Omit type, or set it to "Results". Messages with any other type are ignored.
The connection closes after 90 seconds without activity.

Your Own Keys & Custom Transcription

Where to configure a custom provider in the app

Capture & Transcription

How transcription fits into the rest of Omi