Basic Web Audio API not playing a mp3 file?

Question

I'm trying to follow a tutorial online by piecing together the examples. I feel like this should be playing the mp3 file. I'm using the Chrome browser and it's up to date. I don't get any errors on the console. I'm not sure what I need to change or add to make this work.

<script type="text/javascript">

//creating an audio context

window.addEventListener('load',init);

function init()
{

    try
    {
        window.AudioContext = window.AudioContext || window.webkitAudioContext;
        var context=new AudioContext();

    }
    catch(e)
    {
        alert("Your browser doesn't support Web Audio API");
    }

    loadSound();
    playSound();
}

//loading sound into the created audio context

function loadSound()
{
    //set the audio file's URL
    var audioURL='audio files/song.mp3';

    //creating a new request
    var request = new XMLhttpRequest();
    request.open("GET",audioURL,true);
    request.responseType= 'arraybuffer';
    request.onLoad funtion(){

        //take the audio from http request and decode it in an audio buffer

        var audioBuffer = null;

        context.decodeAudioData(request.response, function(buffer){ audioBuffer= buffer;});

    }

    request.send();

}, onError);

//playing the audio file
function playSound(buffer) {
  //creating source node
  var source = audioContext.createBufferSource();
  //passing in file
  source.buffer = audioBuffer;

  //start playing
  source.start(0);
}

</script>

</head>


</html>

Answer 1

You are using async XMLHttpRequest (note that it should be spelled by capital "H"), so most probably playSound function is called before request.onLoad (note: missing = ) completes.

Try to trace execution of your script using console.log or similar to find bugs like this and use JavaScript Console to catch syntax errors.

Answer 2

i got this thing fixed :) i made use of audio tag along with web audio API. here's the code :

var audio = new Audio();
audio.src = 'audio files/song.mp3';
audio.controls = true;
audio.autoplay = true;
document.body.appendChild(audio);

var context = new webkitAudioContext();
var analyser = context.createAnalyser();


window.addEventListener('load', function(e) {
  // Our <audio> element will be the audio source.
  var source = context.createMediaElementSource(audio);
  source.connect(analyser);
  analyser.connect(context.destination);


}, false);

thnks for trying to help :))

Answer 3

Is your audioURL correct?

audio files/song.mp3 Why is there an empty space?

============Edit============

<script>

//creating an audio context

var context;
var audioBuffer;

window.addEventListener('load', init);    

function init()
{

    try
    {
        window.AudioContext = window.AudioContext || window.webkitAudioContext;
        context=new AudioContext();

    }
    catch(e)
    {
        alert("Your browser doesn't support Web Audio API");
    }

    loadSound();
    // playSound();  // comment here
}

//loading sound into the created audio context
function loadSound()
{
    // set the audio file's URL
    var audioURL='AllofMe.mp3';

    //creating a new request
    var request = new XMLHttpRequest();
    request.open("GET",audioURL,true);
    request.responseType= 'arraybuffer';
    request.onload = function(){

        //take the audio from http request and decode it in an audio buffer
        context.decodeAudioData(request.response, function(buffer){
          audioBuffer = buffer;
          console.log(audioBuffer);
          if(audioBuffer){  // check here
            playSound();
          }
        });

    };

    request.send();

}



//playing the audio file
function playSound() {

    //creating source node
    var source = context.createBufferSource();
    //passing in file
    source.buffer = audioBuffer;

    //start playing
    source.connect(context.destination);  // added
    source.start(0);
    console.log('playing');

}

</script>

Answer 4

I was looking for the solution to play mp3 on a mobile device, and found this page, I've made provided example to work with a help from here . Providing working example below:

var context;
var saved;

try {
    context = new (window.AudioContext || window.webkitAudioContext)();
}
catch (e) {
    console.log("Your browser doesn't support Web Audio API");
}

if (saved) {
    playSound(saved);
} else {
    loadSound();
}

//loading sound into the created audio context
function loadSound() {
    //set the audio file's URL
    var audioURL = '/path/to/file.mp3';

    //creating a new request
    var request = new XMLHttpRequest();
    request.open('GET', audioURL, true);
    request.responseType = 'arraybuffer';
    request.onload = function () {
        //take the audio from http request and decode it in an audio buffer
        context.decodeAudioData(request.response, function (buffer) {
            // save buffer, to not load again
            saved = buffer;
            // play sound
            playSound(buffer);
        });
    };
    request.send();
}

//playing the audio file
function playSound(buffer) {
    //creating source node
    var source = context.createBufferSource();
    //passing in data
    source.buffer = buffer;
    //giving the source which sound to play
    source.connect(context.destination);
    //start playing
    source.start(0);
}

It looks like playing files works fine on Android device, but not iOS. For that you have to follow this guide: How to: Web Audio on iOS (but use touchend event and replace noteOn method to start ).

Answer 5

I'm trying to follow a tutorial online by piecing together the examples. I feel like this should be playing the mp3 file. I'm using the Chrome browser and it's up to date. I don't get any errors on the console. I'm not sure what I need to change or add to make this work.

<script type="text/javascript">

//creating an audio context

window.addEventListener('load',init);

function init()
{

    try
    {
        window.AudioContext = window.AudioContext || window.webkitAudioContext;
        var context=new AudioContext();

    }
    catch(e)
    {
        alert("Your browser doesn't support Web Audio API");
    }

    loadSound();
    playSound();
}

//loading sound into the created audio context

function loadSound()
{
    //set the audio file's URL
    var audioURL='audio files/song.mp3';

    //creating a new request
    var request = new XMLhttpRequest();
    request.open("GET",audioURL,true);
    request.responseType= 'arraybuffer';
    request.onLoad funtion(){

        //take the audio from http request and decode it in an audio buffer

        var audioBuffer = null;

        context.decodeAudioData(request.response, function(buffer){ audioBuffer= buffer;});

    }

    request.send();

}, onError);

//playing the audio file
function playSound(buffer) {
  //creating source node
  var source = audioContext.createBufferSource();
  //passing in file
  source.buffer = audioBuffer;

  //start playing
  source.start(0);
}

</script>

</head>


</html>