Text to speech using the default macOS "say" command. No need for 3rd party APIs or models. Supports many languages. Also, Trinoids!

---

name: say-tts description: Local text-to-speech using macOS say + ffmpeg for Telegram/Matrix voice messages homepage: https://github.com metadata: { "openclaw": { "emoji": "🎤", "requires": { "bins": ["say", "ffmpeg"] }, "label": "Local TTS via say + ffmpeg" } }

---

Say + FFmpeg TTS Pipeline

Use say (macOS native TTS) + ffmpeg to generate Opus voice messages for Telegram/Matrix.

Why not just say?

Telegram/Matrix require Opus codec voice messages

say outputs AIFF/m4a; must convert to .ogg (Opus) before sending

Telegram accepts: OGG/MP3/M4A as voice — but Opus OGG is the native format

Workflow

say -v "" -o /.aiff ""
ffmpeg -i /.aiff -acodec libopus /.ogg -y

Send with message tool:

{
  "action": "send",
  "channel": "telegram",
  "media": "/.ogg",
  "asVoice": true,
  "target": ""
}

Recommended workspace directory

~/.openclaw/workspace/tmp/audio/

(Whitelist this path in exec permissions for faster approval)

Voice selection

Use say -v '?' to list available voices. Notable ones:

Trinoids — robotic/electronic voice (popular for bots)

Samantha — warm US female voice

Alex — US male voice

Fred — neutral US male voice

Karen — Australian female voice

Note: pass just the voice name (e.g. "Trinoids"), not the full en_US suffix.

Example: send a hello voice message

VOICE="Trinoids"
TEXT="Hello!"
DIR="$HOME/.openclaw/workspace/tmp/audio"
mkdir -p "$DIR"
say -v "$VOICE" -o "$DIR/hello.aiff" "$TEXT"
ffmpeg -i "$DIR/hello.aiff" -acodec libopus "$DIR/hello.ogg" -y
Then send via message tool with asVoice: true

Format notes

Input to ffmpeg: AIFF (.aiff) works reliably; avoid .m4a with say

Output: Opus in Ogg container (libopus codec) — required for Telegram voice messages

Telegram sendVoice accepts: OGG, MP3, M4A — but native is Opus OGG

Sample rate: say outputs 24kHz AIFF; ffmpeg re-encodes to Opus at 24kHz

Integration with OpenClaw TTS

OpenClaw's built-in messages.tts only supports: ElevenLabs, Microsoft Edge, MiniMax, OpenAI.

This say+ffmpeg pipeline is a workaround for local-only TTS without API keys or cloud services. It's not auto-triggered by OpenClaw — call it manually via exec + message tool.

Language Detection → Voice Mapping

When responding to a voice message, detect the language from the STT output (Parakeet auto-detects). Then pick the matching say voice using i18n locale codes.

Finding voices by language:

say -v '?' 2>&1 | grep -E "cs_CZ|en_US|de_DE|fr_FR|it_IT|es_ES"

Language → voice selection priority: 1. Use (Premium) if available 2. Fall back to (Enhanced) if available 3. Fall back to base name 4. Never use a voice that doesn't match the language

| Language | i18n code | Preferred Voice | |---|---|---| | Czech | cs_CZ | Zuzana (Premium) | | English (US) | en_US | Trinoids (no Premium/Enhanced available) | | German | de_DE | Grandma (Premium) if available | | French | fr_FR | Grandma (Premium) if available | | Spanish | es_ES | Grandma (Premium) if available | | Italian | it_IT | Grandma (Premium) if available |

Key: Always use just the voice name (e.g. "Trinoids", "Zuzana"), not the full locale suffix. The locale suffix in say -v '?' output is for grepping/identification only.

Example workflow:

LANG="cs_CZ"
Find best available voice for this language (Premium > Enhanced > base)
VOICE=$(say -v '?' 2>&1 | grep "$LANG" | head -3 | awk '{print $1}' | sed -n '1p')
say -v "$VOICE" -o reply.aiff "Česká odpověď"
ffmpeg -i reply.aiff -acodec libopus reply.ogg -y

TODOs

[ ] Detect language from STT transcription and auto-select appropriate say voice

[ ] Explore integrating into OpenClaw via custom TTS provider plugin

[ ] Investigate if OpenClaw supports post-processing TTS output via a hook

[ ] Test Matrix channel voice message format compatibility