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Detecting WebAudio sound end

I'm using a javascript build a radio and I'm trying to give it different functionalities but I need to be able to detect the end of a song to make it work. Is there any way to do this?
I've tried different methods I've found online like .ended and such but I don't think those work without using the html audio tag. So I tried to make an audio tag that uses the same data for the source that my js radio uses and get the file length to stop my sourceNode at the end time and make a new one but but i keep getting null returned as the data so that doesn't work either.
I want to do something like:
context.onended = function() {
$.ajax({
url: '../scripts/radio.php',
data: {
attr1: 'value1'
},
success: function(data) {
console.log(data);
fileChosen = true;
setupAudioNodes();
var request = new XMLHttpRequest();
request.addEventListener("progress", updateProgress);
request.addEventListener("load", transferComplete);
request.addEventListener("error", transferFailed);
request.addEventListener("abort", transferCanceled);
request.open('GET', data, true);
request.responseType = 'arraybuffer';
// When loaded decode the data
request.onload = function() {
$("#title").html("Title");
$("#album").html("Goes");
$("#artist").html("Here");
onWindowResize();
$("#title, #artist, #album").css("visibility", "visible");
// decode the data
context.decodeAudioData(request.response, function(buffer) {
// when the audio is decoded play the sound
sourceNode.buffer = buffer;
sourceNode.start(0);
$("#freq, body").addClass("animateHue");
//on error
}, function(e) {
console.log(e);
});
};
request.send();
}
});
I want for this to run at the end of a song and play the next file. Which it would work if I could get the end time of the currently playing song.

To fix the above issue I added the .ended event inside the function that the source was set up:
function setupAudioNodes() {
// setup a analyser
analyser = context.createAnalyser();
// create a buffer source node
sourceNode = context.createBufferSource();
//connect source to analyser as link
sourceNode.connect(analyser);
// and connect source to destination
sourceNode.connect(context.destination);
//start updating
rafID = window.requestAnimationFrame(updateVisualization);
//I had to place a function for the .ended event inside the function sourceNode was set up.
sourceNode.onended = function() {
sourceNode.stop(0);
playFirst();
}
}

URL.createObjectURL(blob) not creating proper URL in IE 11

I'm trying to render a pdf inside an iframe. It is working fine on Mozilla (v54) and Chrome (v59) but nothing happens in IE(v11) when I click on the link which loads the PDF. After debugging several times I found that the URL in Chrome/Firefox is blob:http://localhost:37444/5a8e7fed-cd61-4c58-904c-fad2ae169718 and in IE(v11) it is blob:B7395CB5-169D-471F-BB8F-AA90EAFB6DDB. Why is URL.createObjectURL(blob) not appending the http request in IE(v11)
function (iframe, url, headers) {
var xhr = new XMLHttpRequest();
xhr.open('GET', url);
xhr.onreadystatechange = handler;
xhr.responseType = "arraybuffer";
headers.forEach(function (header) {
xhr.setRequestHeader(header[0], header[1]);
});
xhr.send();
function handler() {
if (this.readyState === this.DONE) {
if (this.status === 200) {
var blob = new Blob([xhr.response], { type: "application/pdf" });
var objectUrl = URL.createObjectURL(blob);
iframe.src = objectUrl;
} else {
console.error('XHR failed', this);
}
}
}

IE does not create a url for these blob objects because of security reasons i think.So using var objectUrl = URL.createObjectURL(blob);will not give you the source url which you can use inside iframe or embed tag.
I faced the same issue and searched a lot about the fix.But could not get the answer.Instead i solved it as following.
you can use the following for IE
if (bowser.msie && window.navigator.msSaveOrOpenBlob) {
navigator.msSaveOrOpenBlob(file, fileName);
}else{
//do what you were doing for other than IE
}
the above IE code will prompt the user that whether he wants to save the file or directly open it.
User can click on button 'open' and then IE will show the PDF without downloading it in default reader.

How to play a video in a Seamless loop using media source extensions

I am working on media source extension to play the video in a seamless loop without any delay. I have done an extensive r&d about it and also done different things. Now i am working on this code
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
</head>
<body>
<video controls></video>
<script>
var video = document.querySelector('video');
var assetURL = 'test1.mp4';
// Need to be specific for Blink regarding codecs
// ./mp4info frag_bunny.mp4 | grep Codec
var mimeCodec = 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"';
if ('MediaSource' in window && MediaSource.isTypeSupported(mimeCodec)) {
var mediaSource = new MediaSource;
//console.log(mediaSource.readyState); // closed
video.src = URL.createObjectURL(mediaSource);
mediaSource.addEventListener('sourceopen', sourceOpen);
} else {
console.error('Unsupported MIME type or codec: ', mimeCodec);
}
function sourceOpen (_) {
//console.log(this.readyState); // open
var mediaSource = this;
var sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
fetchAB(assetURL, function (buf) {
sourceBuffer.addEventListener('updateend', function (_) {
mediaSource.endOfStream();
video.play();
//console.log(mediaSource.readyState); // ended
});
sourceBuffer.appendBuffer(buf);
});
};
function fetchAB (url, cb) {
console.log(url);
var xhr = new XMLHttpRequest;
xhr.open('get', url);
xhr.responseType = 'arraybuffer';
xhr.onload = function () {
cb(xhr.response);
};
xhr.send();
};
</script>
</body>
</html>
It is working fine but the video is playing again with a slight delay. I want to play the video without any delay and I know that it is possible with media source extensions but after spending a lot of time still didn't get any idea that how to do it. Any help would be really appreciated. Thanks

Setting the mode value to sequence worked for me, it ensures continuous media playback, no matter if the media segment timestamps were discontinuous.
sourceBuffer.mode = 'sequence';

May be this code solve Your Problem ....play the video in a seamless loop without any delay
for (let chunk of media) {
await new Promise(resolve => {
sourceBuffer.appendBuffer(chunk.mediaBuffer);
sourceBuffer.onupdateend = e => {
sourceBuffer.onupdateend = null;
sourceBuffer.timestampOffset += chunk.mediaDuration;
console.log(mediaSource.duration);
resolve()
}
})
}
if you need more information visit this link.....
http://www.esjay.org/2020/01/01/videos-play-without-buffering-in-javascript/

You can't really do that because it really depends on how fast your PC runs. Its delay should only be there if you have a slow PC but if not it shouldn't have a noticeable delay. Maybe the video that you have is big or it just delays inside the video because only thing I could tell you is autoplay loop inside the videos element as a attribute unless you find a way to replay the video before the video ends but even if it doesn't delay for you it may delay big or just play over the video for others

#CoolOppo
The simplest thing to do is to just rewind the video when it reaches it's end time (duration).
See demo here: https://vc-lut.000webhostapp.com/demos/public/mse_loop_example1.html
(to play video just click the picture part, since no controls for looping background)
The code:
<!DOCTYPE html>
<html>
<head> <meta charset="utf-8"/> </head>
<body>
<div>
<video id="video_mse" > </video>
</div>
<script>
var assetURL = "testloop.mp4";
//# use correct mime/codecs or else Error is "source not open"...
var mimeCodec = 'video/mp4; codecs="avc1.42C01E"';
var mediaSource; var sourceBuffer;
var video = document.getElementById( "video_mse" );
video.onclick = vid_togglePlay; //# for playing/pausing
video.ontimeupdate = vid_checkTime; //# for looping
//# handle play/pause (because controls are hidden)
function vid_togglePlay()
{
if( video.paused == true ) { video.play(); }
else { video.pause(); }
}
//# handle looping...
function vid_checkTime()
{
if( video.currentTime == video.duration)
{
video.currentTime = 0;
video.play();
}
}
if ( 'MediaSource' in window && MediaSource.isTypeSupported(mimeCodec) )
{
mediaSource = new MediaSource;
video.src = URL.createObjectURL(mediaSource);
mediaSource.addEventListener('sourceopen', sourceOpen);
}
else
{ console.error('Unsupported MIME type or codec: ', mimeCodec); }
function sourceOpen()
{
//console.log(this.readyState); // open
var mediaSource = this;
sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
fetchAB(assetURL, function (buf) {
sourceBuffer.addEventListener('updateend', function() {
mediaSource.endOfStream();
video.play();
});
sourceBuffer.appendBuffer(buf);
});
};
function fetchAB (url, callbackfunc )
{
console.log("loading file: " + url);
var xhr = new XMLHttpRequest;
xhr.open('get', url);
xhr.responseType = 'arraybuffer';
xhr.onload = function() { callbackfunc( xhr.response ); }
xhr.send();
}
</script>
</body>
</html>

Storing Image In Database Without JQuery

Good day stackers,
I'm working on a web project in which we recreate a social media site similar to snapchat. I'm using my webcam to take pictures using JS, and I'm writing the picture to a var called img as follows:
var img = canvas.toDataURL("image/png");
We are required to use PDO in PHP to access the database. Alternatively we can use AJAX, but JQuery is strictly forbidden. My question is, how can I store the DataURL inside my database? All the tutorials online use JQuery.
Update:
I followed the steps as suggested below, but when I hit the snap button, it still only takes the picture, but no URL or nothing.
function sendimagetourl(image)
{
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function()
{
if (this.readyState == 4 && this.status == 200)
{
alert( this.resoponseText);
}
}
xhtp.open("GET", "saveimage.php?url="+image, true);
xhttp.send();
}
//Stream Video
if (navigator.mediaDevices && navigator.mediaDevices.getUserMedia)
{
navigator.mediaDevices.getUserMedia({video: true}).then(function(stream) {
video.src = window.URL.createObjectURL(stream);
video.play();
});
}
//Snap Photo
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var video = document.getElementById('video');
document.getElementById("snap").addEventListener("click", function() {context.drawImage(video, 0, 0, 800, 600);var image = canvas.toDataURL("image/png"); sendimagetourl(image);});
So it appears I was a bit of a fool. There were two minor typos, and it seems like the data sent is invisible in the url. Thanks for all the help!

You can use javascript ajax
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
alert( this.responseText);
}
};
xhttp.open("GET", "saveimage.php?url="+url, true);
xhttp.send();

You can use XMLHttpRequest() or fetch(), Blob, FormData to POST data URI to php. See also Using files from web applications
var request = new XMLHttpRequest();
request.open("POST", "/path/to/server", true);
request.onload = function() {
// do stuff
}
var data = new FormData();
data.append("image", new Blob([img], {type:"image/png"}), "filename");
request.send(data);

Does the "preload" attribute of <audio> affect the window.onload event time?

I have assumed (possibly incorrectly?), due to the asynchronous nature of HTML, that the timeline of page loading is as follows:
... etc loading html into DOM
encounter <audio> tag
preload is specified as "auto"; trigger buffering
continue loading html into DOM... etc
fire window.onload event callbacks
asynchronously some time later: audio resource is found, begin buffering, or server error is returned; fire readystatechange event callbacks
Whereas what I'm hoping for is that the preload attribute with a value of "auto" will delay the window.onload event from firing or delay tag-to-DOM processing until the audio resource is found and has had begun buffering, or a server error is returned and loading is canceled.
I can't imagine withholding window.onload for an audio resource, but then I have seen page processing come to a halt for flash resource loading or tracking script loading in the past.
TLDR: What is the exact timeline of window.onload with regard to resource loading--specifically the audio tag?

window.onload event appears to be called before the media src is fully loaded. Using approaches described at How do you check if a HTML5 audio element is loaded? ; and including .webkitAudioDecodedByteCount
<!DOCTYPE html>
<html>
<head>
<script>
window.addEventListener("load", function() {
var media = document.querySelector("audio");
console.log("window onload event"
, media.webkitAudioDecodedByteCount
, media.readyState)
})
function myOnCanPlayFunction() {
console.log("Can play", event.target.webkitAudioDecodedByteCount
, event.target.seekable.start(0)
, event.target.seekable.end(0));
}
function myOnCanPlayThroughFunction() {
console.log("Can play through", event.target.webkitAudioDecodedByteCount
, event.target.seekable.start(0)
, event.target.seekable.end(0));
}
function myOnLoadedData() {
console.log("Loaded data", event.target.webkitAudioDecodedByteCount
, event.target.seekable.start(0)
, event.target.seekable.end(0));
}
</script>
</head>
<body>
<audio oncanplay="myOnCanPlayFunction()"
oncanplaythrough="myOnCanPlayThroughFunction()"
onloadeddata="myOnLoadedData()"
src="/path/to/audio/file"
preload autoplay buffered controls></audio>
</body>
</html>
plnkr version 1 http://plnkr.co/edit/zIIDDLZeVU7NHdfAtFka?p=preview
An alternative approach using XMLHttpRequest , onended event of AudioContext; Promise; recursion to request, play array of files in sequence. See AudioContext.decodeAudioData()
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="style.css">
<script>
var sources = ["/path/to/audio/src/1"
, "/path/to/audio/src/2"];
var src = sources.slice(0); // copy original array
function getAudio(url) {
return new Promise(function(resolve, reject) {
var audioCtx = new(window.AudioContext || window.webkitAudioContext)();
var source = audioCtx.createBufferSource();
var request = new XMLHttpRequest();
request.open("GET", url, true);
request.responseType = "arraybuffer";
request.onload = function() {
var audioData = request.response;
audioCtx.decodeAudioData(audioData).then(function(decodedData) {
source.buffer = decodedData;
source.connect(audioCtx.destination);
console.log(source, decodedData);
// do stuff when current audio has ended
source.onended = function() {
console.log("onended:", url);
if (src.length)
resolve(src)
else resolve("complete")
}
source.start(0);
});
}
request.send();
})
}
var audio = (function tracks(s) {
return getAudio(s.shift())
.then(function(data) {
if (Array.isArray(data) && data.length) return tracks(data)
else return data
})
}(src));
// do stuff when all `src` have been requested, played, ended
audio.then(function(msg) {
console.log(msg)
})
</script>
</head>
<body>
</body>
</html>
plnkr version 2 http://plnkr.co/edit/zIIDDLZeVU7NHdfAtFka?p=preview