If you don’t know about it yet, the HTML5 web speech api specification is now in a working condition on google chrome and partially in apple safari browser(See the browser support status here: http://caniuse.com/web-speech). That means, you can now develop voice driven web applications. We can hope that other browsers will start supporting this very soon as well. In this tutorial, I will try to explain how we can start developing application that uses this and also refer you to a small wrapper library with easy to use abstraction that I wrote recently.
Voice To Text API:
We can alternatively mention it as ‘Speech Recognition API’ as well. What it does, is to capture user’s voice through input system and convert it to text. So, basically there is a need of voice recognition technology here. This feature is currently supported only in Google Chrome browser. By default, it uses google’s own voice recognition service. Here is a code example to implement it:
var recognizer = new webkitSpeechRecognition();
recognizer.lang = "en";
recognizer.onresult = function(event) {
if (event.results.length > 0) {
var result = event.results[event.results.length-1];
if(result.isFinal) {
console.log(result[0].transcript);
}
}
};
recognizer.start();
The above code snippet will request permission from user to allow taking input through microphone access and then will capture the sound you talk, send it to external service for recognition, and get the result back inside ‘onresult’ event handler. Thus, we will be able to see the output in console window of browser.
This class definition also exposes an optional ‘serviceURI’ property which you can use to define the service url you like to use for voice recognition.
Text To Voice API:
Text to voice conversion is just a simple way to play a given text in robotic voice. Here is a simple code snippet for this:
var su = new SpeechSynthesisUtterance(); su.lang = "en"; su.text = "Hello World"; speechSynthesis.speak(su);
As you can see, its pretty much straight forward. Where we just need to pass the desired language and text to it and its all set to play it.
Checkout The HTML5 Web Speech Demo!
The Wrapper Library And Usage Example:
As I already experienced, some of the steps are obvious and can be made simple with a simple wrapper. Thus, to make your life easier, I started a small JavaScript library to ease the use of this api. Here is the github link:
https://github.com/ranacseruet/webspeech
It’s also registered as a bower package too! So, if you are using bower for front end package management, you can simply run command like:
$bower install webspeech
And you should be just fine!
Here is a very simple to use example:
<input id="text">
<button onclick="talk()">Talk It!</button>
<button onclick="listen()">Voice</button>
<script src="../bower_components/platform/platform.js"></script>
<script src="../src/webspeech.js"></script>
<script>
var speaker = new webspeech.Speaker();
var listener = new webspeech.Listener();
function talk() {
speaker.speak("en", document.getElementById("text").value);
}
function listen() {
listener.listen("en", function(text) {
document.getElementById("text").value = text;
});
}
</script>
Final Words:
Even on in chrome for windows, there is another issue, which is like it doesn’t support capturing voice continuously, instead, you will have to allow it on browser every time you want to say something. However, there is a work around to get rid of this annoying access allowance, which is to host your application on SSL. Then, only one time access will work for all later times.
Hope this simple tutorial will help you to get started with HTML5 web speech API easily without much difficulty. In case you are facing some issues, please let me know via commenting. Happy coding 🙂
tung says
August 2, 2015 at 4:03 amUseful. Thank you!
Girish says
September 9, 2015 at 11:43 pmHi
From where can i download the ../bower_components/platform/platform.js file
Md Ali Ahsan Rana says
October 8, 2015 at 8:11 pmPlease refer to ‘install’ section on the documention: https://github.com/ranacseruet/webspeech . Hope it helps.
serdar says
November 13, 2015 at 9:16 amhi , it was work thank you , vut how can ı change language? ı want to use turkish. this is posible can you help me how can ı do it.
with the best regards.
Pelle B says
September 30, 2015 at 5:12 pmAmazing! Do you know if it´s ok to use this Voice-To-Text-API for commercial use?
Md Ali Ahsan Rana says
October 8, 2015 at 8:17 pmDon’t have much idea. But if its web app and as browsers are starting to support it, I don’t see much of a problem in any way.
cardoso says
October 13, 2015 at 10:41 pmtext-to-voice ok, but voice-to-text don’t work why?
Tomas Feliciano says
November 12, 2015 at 3:11 amexcuse me. but where is the ../bower_components/platform/platform.js file and also why the voice to text doesn’t work.
Rajendra Jangir says
December 14, 2016 at 7:27 amHey Tomas,
If you replace the bower_components to node_modules. It’ll work.
Nate says
December 18, 2015 at 12:09 pmHow can you implement this on visual studio, I am trying to create an asp.net mvc site that allows speech to text and then translation of that text. I need the speech recognition to be able to understand arabic and translate it to english.
s says
April 6, 2016 at 12:29 pmThe text to voice conversion works fine for me. But voice-text isn’t working. Please help me. Do I need upload the files to webserver?
Ali Sounblé says
April 9, 2017 at 6:04 amHello Sir,
i need to use the web API speech to text converter and insert it in my matlab script, how can copy the converted voice data i mean the text to a separated text file?
please advise.
thanks in advance
achilles ram says
April 26, 2017 at 1:55 pmis not working for telugu script?? why could you please explian???
Tcharles says
May 10, 2017 at 5:34 amDear Mr Md Ali Ahsan Rana
About your article bellow, I think it’s great. I’m a student, and I really like this part of the computer science. I wonder if you can help me with an issue?
Talk It!
Voice
http://../bower_components/platform/platform.js
http://../src/webspeech.js
var speaker = new webspeech.Speaker();
var listener = new webspeech.Listener();
function talk() {
speaker.speak(“en”, document.getElementById(“text”).value);
}
function listen() {
listener.listen(“en”, function(text) {
document.getElementById(“text”).value = text;
});
}
How can I do, in the article above, to store “text” in a variable?
I wish I could use this variable later, for another purpose.
Your command line:
Speaker.speak (“en”, document.getElementById (“text”).
Just get the id = “text” value, and use spearker.speak. However, once this line has been made, I no longer have access to this value.
I would like to be able to store the “text” in a variable and display it on the screen to verify that it was actually stored. Can you help?
tank you,
Tcharles
Muthukaliswaran says
March 9, 2019 at 12:58 pmIam using four text boxes in my html code and i want the html5 web speech api to read all the four text box value, but it reads only the last text textbox value. Can you help me! what goes wrong?