This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for the proper prefixes to use in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the spec changes.
The onstart property of the SpeechRecognition interface represents an event handler that will run when the speech recognition service has begun listening to incoming audio with intent to recognize grammars associated with the current SpeechRecognition (when the start event fires.)
Syntax
mySpeechRecognition.onstart = function() { ... };
Examples
recognition.onstart = function() {
console.log('Speech recognition service has started');
}
Specifications
| Specification | Status | Comment |
|---|---|---|
| Web Speech API The definition of 'onstart' in that specification. |
Draft |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 33 [1] | 44 (44) [2] | Not supported | Not supported | Not supported |
| Feature | Android | Chrome | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic support | ? | (Yes)[1] | ? | 2.5 | Not supported | Not supported | Not supported |
- [1] Speech recognition interfaces are currently prefixed on Chrome, so you'll need to prefix interface names appropriately, e.g.
webkitSpeechRecognition; You'll also need to serve your code through a web server for recognition to work. - [2] Can be enabled via the
media.webspeech.recognition.enableflag in about:config, although note that currently speech recognition won't work on Desktop Firefox — it will be properly exposed soon, once the required internal permissions are sorted out.
Firefox OS permissions
To use speech recognition in an app, you need to specify the following permissions in your manifest:
"permissions": {
"audio-capture" : {
"description" : "Audio capture"
},
"speech-recognition" : {
"description" : "Speech recognition"
}
}
You also need a privileged app, so you need to include this as well:
"type": "privileged"