From http://stackoverflow.com/questions/27851832/how-do-i-parse-an-iso-8601-formatted-duration-using-moment-js

youtube duration convert.js

var regex = /P((([0-9]*\.?[0-9]*)Y)?(([0-9]*\.?[0-9]*)M)?(([0-9]*\.?[0-9]*)W)?(([0-9]*\.?[0-9]*)D)?)?(T(([0-9]*\.?[0-9]*)H)?(([0-9]*\.?[0-9]*)M)?(([0-9]*\.?[0-9]*)S)?)?/

minutesFromIsoDuration = function(duration) {
    var matches = duration.match(regex);

    return parseFloat(matches[14]) || 0;
}

function youtube_parser(url) {
    var regExp = /^.*((youtu.be\/)|(v\/)|(\/u\/\w\/)|(embed\/)|(watch\?))\??v?=?([^#\&\?]*).*/;
    var match = url.match(regExp);
    if (match && match[7].length == 11) {
        return match[7];
    } else {
        alert("Link YouTube Không đúng");
        return '';
    }
}