Tauri Plugin STT (Speech-to-Text)

Cross-platform speech recognition plugin for Tauri 2.x applications. Provides real-time speech-to-text functionality for desktop (Windows, macOS, Linux) and mobile (iOS, Android).

Features

- 🎤 Real-time Speech Recognition - Convert speech to text with low latency
- 📱 Cross-platform Support - iOS, Android, macOS, Windows, Linux
- 🌐 Multi-language Support - 9 languages with automatic model download
- 📝 Interim Results - Get partial transcriptions while speaking
- 🔄 Continuous Mode - Auto-restart recognition after each utterance
- 🔐 Permission Handling - Request and check microphone/speech permissions
- 📥 Auto Model Download - Vosk models are downloaded automatically on first use

Platform Support

| Platform | Status | API Used | Model Download |
| -------- | ------- | ------------------------------------- | -------------- |
| iOS | ✅ Full | SFSpeechRecognizer (Speech framework) | Not required |
| Android | ✅ Full | SpeechRecognizer API | Not required |
| macOS | ✅ Full | Vosk (offline speech recognition) | Automatic |
| Windows | ✅ Full | Vosk (offline speech recognition) | Automatic |
| Linux | ✅ Full | Vosk (offline speech recognition) | Automatic |

Supported Languages (Desktop)

| Language | Code | Model Size |
| ---------- | ----- | ---------- |
| English | en-US | 40 MB |
| Portuguese | pt-BR | 31 MB |
| Spanish | es-ES | 39 MB |
| French | fr-FR | 41 MB |
| German | de-DE | 45 MB |
| Russian | ru-RU | 45 MB |
| Chinese | zh-CN | 43 MB |
| Japanese | ja-JP | 48 MB |
| Italian | it-IT | 39 MB |

Models are downloaded automatically from alphacephei.com/vosk/models when you first use a language.

Installation

$3

Add the plugin to your Cargo.toml:

``toml
[dependencies]
tauri-plugin-stt = "0.1"
`

$3

Install the JavaScript guest bindings:

`bash
npm install tauri-plugin-stt-api


or

yarn add tauri-plugin-stt-api

or

pnpm add tauri-plugin-stt-api
`

Setup

$3

In your Tauri app setup:

`rust
fn main() {
tauri::Builder::default()
.plugin(tauri_plugin_stt::init())
.run(tauri::generate_context!())
.expect("error while running application");
}
`

$3

Add permissions to your capabilities/default.json:

`json
{
"permissions": ["stt:default"]
}
`

For granular permissions, you can specify individual commands:

`json
{
"permissions": [
"stt:allow-is-available",
"stt:allow-get-supported-languages",
"stt:allow-check-permission",
"stt:allow-request-permission",
"stt:allow-start-listening",
"stt:allow-stop-listening",
"stt:allow-register-listener",
"stt:allow-remove-listener"
]
}
`

For granular permissions, you can specify individual commands:

`json
{
"permissions": [
"stt:allow-is-available",
"stt:allow-get-supported-languages",
"stt:allow-check-permission",
"stt:allow-request-permission",
"stt:allow-start-listening",
"stt:allow-stop-listening",
"stt:allow-register-listener",
"stt:allow-remove-listener"
]
}
`

$3

The Vosk runtime library must be installed on your system:

#### macOS

`bash


Download and install libvosk


curl -LO https://github.com/alphacep/vosk-api/releases/download/v0.3.42/vosk-osx-0.3.42.zip
unzip vosk-osx-0.3.42.zip
sudo cp vosk-osx-0.3.42/libvosk.dylib /usr/local/lib/
`

#### Linux

`bash
wget https://github.com/alphacep/vosk-api/releases/download/v0.3.42/vosk-linux-x86_64-0.3.42.zip
unzip vosk-linux-x86_64-0.3.42.zip
sudo cp vosk-linux-x86_64-0.3.42/libvosk.so /usr/local/lib/
sudo ldconfig
`

#### Windows

Download from GitHub Releases and add to PATH.

Usage

$3

`typescript
import {
isAvailable,
getSupportedLanguages,
startListening,
stopListening,
onResult,
onStateChange,
onError,
} from "tauri-plugin-stt-api";

// Check if STT is available
const result = await isAvailable();

// Get supported languages (with installed status)
const languages = await getSupportedLanguages();

// Listen for results
const resultListener = await onResult(result => {
console.log("Recognized:", result.transcript, result.isFinal);
});

// Listen for download progress (when model is being downloaded)
import { listen } from "@tauri-apps/api/event";
const downloadListener = await listen<{
status: string;
model: string;
progress: number;
}>("stt://download-progress", event => {
console.log(${event.payload.status}: ${event.payload.progress}%);
});

// Start listening
await startListening({
language: "en-US",
interimResults: true,
continuous: true,
// maxDuration and onDevice are supported by the guest SDK
});

// Stop listening
await stopListening();
`

$3

`typescript
interface ListenConfig {
language?: string; // Language code (e.g., "en-US", "pt-BR")
interimResults?: boolean; // Return partial results while speaking
continuous?: boolean; // Continue listening after utterance ends
maxDuration?: number; // Max listening duration in milliseconds (0 = unlimited)
onDevice?: boolean; // Prefer on-device recognition (iOS)
}
`

$3

`typescript
// Listen for results
const unlistenResult = await onResult(result => {
console.log(result.transcript, result.isFinal);
});

// Listen for state changes
const unlistenState = await onStateChange(event => {
console.log("State:", event.state); // "idle" | "listening" | "processing"
});

// Listen for errors
const unlistenError = await onError(error => {
console.error([${error.code}] ${error.message});
});

// Clean up listeners
unlistenResult();
unlistenState();
unlistenError();
`

Events

| Event | Payload | Description |
| ------------------------- | -------------------------------------- | ---------------------------------------- |
| stt://result | { transcript, isFinal, confidence? } | Recognition result |
| stt://state-change | { state } | State change (idle/listening/processing) |
| stt://error | { code, message, details? } | Error event |
| stt://download-progress | { status, model, progress } | Model download progress |

API Reference

$3

Start speech recognition.

Config Options:

- language: Language code (e.g., "en-US", "pt-BR")
- interimResults: Return partial results (default: false)
- continuous: Continue listening after utterance ends (default: false)
- maxDuration: Max listening duration in ms (0 = unlimited)
- onDevice: Use on-device recognition (iOS only, default: false)

$3

Stop current speech recognition session.

$3

Check if STT is available on the device.

Returns:

- available: Whether STT is available
- reason: Optional reason if unavailable

$3

Get list of supported languages.

Returns: Array of languages with:

- code: Language code (e.g., "en-US")
- name: Display name
- installed: Whether model is installed (desktop only)

$3

Check current permission status.

Returns:

- microphone: "granted" | "denied" | "unknown"
- speechRecognition: "granted" | "denied" | "unknown"

$3

Request microphone and speech recognition permissions.

Returns: Same as checkPermission()

$3

Listen for recognition results.

Result:

- transcript: Recognized text
- isFinal: Whether this is a final result
- confidence: Confidence score (0.0-1.0, if available)

$3

Listen for state changes.

States: "idle", "listening", "processing"

$3

Listen for errors.

Error Codes:

- NOT_AVAILABLE: STT not available on device
- PERMISSION_DENIED: Microphone permission denied
- SPEECH_PERMISSION_DENIED: Speech recognition permission denied
- NETWORK_ERROR: Network error (server-based recognition)
- AUDIO_ERROR: Audio capture error
- TIMEOUT: Recognition timeout
- NO_SPEECH: No speech detected
- LANGUAGE_NOT_SUPPORTED: Requested language not supported
- CANCELLED: Recognition cancelled by user
- ALREADY_LISTENING: Already in listening state
- NOT_LISTENING: Not currently listening
- BUSY: Recognizer busy
- UNKNOWN: Unknown error

Building

$3

`bash
npm run dev
`

$3

`bash
npm run dev -- --features stt


or


npm run dev:stt
`

Troubleshooting

$3

Solution: Install the Vosk library as described in the Vosk Library section.

`bash


macOS

ls /usr/local/lib/libvosk.dylib # Should exist

Linux

ldconfig -p | grep vosk # Should show libvosk.so

Windows

where vosk.dll # Should be in PATH
`

$3

Problem: Vosk models are downloaded automatically on first use for each language.

Solution:

1. Ensure internet connectivity
2. Check app data directory: ~/.local/share/tauri-plugin-stt/models/ (Linux/macOS) or %APPDATA%/tauri-plugin-stt/models/ (Windows)
3. Manual download: Download from alphacephei.com/vosk/models and extract to models directory
4. Model naming: Ensure folder name matches expected pattern (e.g., vosk-model-small-en-us-0.15)

$3

iOS Solution:

1. Ensure iOS 10+ (speech recognition requires iOS 10+)
2. Check Settings → Privacy → Speech Recognition → Enable for your app
3. For on-device recognition, iOS 13+ is required

Android Solution:

1. Install Google app (provides speech recognition service)
2. Check Settings → Apps → Default apps → Digital assistant app
3. Ensure internet connectivity for server-based recognition

$3

Solution: Call requestPermission() before startListening()

`typescript
const perm = await requestPermission();
if (perm.microphone !== "granted") {
console.error("Microphone permission required");
return;
}
await startListening();
`

$3

Checklist:

- ✅ Microphone is working in other apps
- ✅ Correct microphone selected in system settings
- ✅ Microphone not muted (hardware or software)
- ✅ App has microphone permission
- ✅ No other app is using the microphone exclusively

$3

Note: Interim results availability varies by platform:

- iOS/Android: Full support
- Desktop (Vosk): Partial support (depends on model)

`typescript
await startListening({
interimResults: true, // Enable interim results
continuous: true, // Keep listening
});
`

$3

Tips:

- Use correct language code for your accent (e.g., "en-GB" vs "en-US")
- Speak clearly and avoid background noise
- On iOS, download enhanced voices in Settings → Accessibility → Spoken Content
- Desktop: Use larger Vosk models for better accuracy (at cost of size)

$3

Solution: Stop current session before starting a new one:

`typescript
try {
await stopListening();
} catch (e) {
// Ignore if not listening
}
await startListening();
`

$3

Note: Download progress events are only for desktop (Vosk models). Mobile uses native speech recognition without downloads.

`typescript
import { listen } from "@tauri-apps/api/event";

const unlisten = await listen("stt://download-progress", event => {
console.log(${event.payload.status}: ${event.payload.progress}%);
});
`

Examples

See the examples/stt-example directory for a complete working demo with React + Material UI, featuring:

- Real-time transcription with interim results
- Language selection
- Permission handling
- Error handling with visual feedback
- Download progress monitoring
- Results history

Platform-Specific Notes

$3

- Requires iOS 10+ for basic speech recognition
- iOS 13+ required for on-device recognition (onDevice: true)
- Must add NSSpeechRecognitionUsageDescription to Info.plist
- Must add NSMicrophoneUsageDescription to Info.plist

$3

- Requires Android API 23+ (Android 6.0+)
- Google app must be installed for speech recognition
- Internet required for server-based recognition
- Must request RECORD_AUDIO` permission in AndroidManifest.xml

$3

- Requires Vosk library installation (see Vosk Library section)
- Models downloaded automatically (40-50 MB per language)
- Fully offline after model download
- Models stored in app data directory

License

MIT