Does Chrome have built-in speech recognition for “x-webkit-speech” input elements?

Question

I\'m wondering how

Is there a speech recognition enging built into Chrome or is it ac

Answer 1

Speech recognition is a proposal by Google. https://docs.google.com/View?id=dcfg79pz_5dhnp23f5

The feature ships with Chrome 8+ and it looks like it sends the data to google servers to perform the actual recognition.

Answer 2

Yes, Chrome does have built-in speech support through WebKit; just look at the Google homepage (which now has a microphone to the right of the search box). I wonder, however, if the Chrome team is working on Omnibox speech support. After all, Chrome is a WebKit-based browser!

Answer 3

There is also a working group that produced http://www.w3.org/TR/xhtml+voice/ but I don't believe this is implemented in any browser except Opera.

Answer 4

According to the code it sends the audio data as a POST request to:

https://www.google.com/speech-api/v1/recognize?client=chromium&lang=??&lm=??&xhw=??&maxresults=3

lm is grammar in the code, xhw is hardware_info which is optional according to a comment. The audio appears to be speex, x-speex-with-header-byte:

// Encode the frame and place the size of the frame as the first byte. This
// is the packet format for MIME type x-speex-with-header-byte.

It looks like it would be pretty trivial to modify the chrome code to use in your own app.

Update:

You also need to get a speech recognition API key and they are limited to 50 requests per day. There is no way to increase that limit - not even by paying.