Obtener el ID de la url de un video en youtube

youtubeID.js

/**
* Get YouTube ID from various YouTube URL
* @author: takien
* @url: http://takien.com
* For PHP YouTube parser, go here http://takien.com/864
*/

function YouTubeGetID(url){
  var ID = '';
  url = url.replace(/(>|<)/gi,'').split(/(vi\/|v=|\/v\/|youtu\.be\/|\/embed\/)/);
  if(url[2] !== undefined) {
    ID = url[2].split(/[^0-9a-z_\-]/i);
    ID = ID[0];
  }
  else {
    ID = url;
  }
    return ID;
}

//Funcion simplificada
function YouTubeGetID(url){
  url = url.split(/(vi\/|v%3D|v=|\/v\/|youtu\.be\/|\/embed\/\/?)/);
  return undefined !== url[2]?url[2].split(/[^0-9a-z_\-]/i)[0]:url[0];
}

/*
* Tested URLs:

var url = 'http://youtube.googleapis.com/v/4e_kz79tjb8?version=3';
url = 'https://www.youtube.com/watch?feature=g-vrec&v=Y1xs_xPb46M';
url = 'http://www.youtube.com/watch?feature=player_embedded&v=Ab25nviakcw#';
url = 'http://youtu.be/Ab25nviakcw';
url = 'http://www.youtube.com/watch?v=Ab25nviakcw';
url = '<iframe width="420" height="315" src="http://www.youtube.com/embed/Ab25nviakcw" frameborder="0" allowfullscreen></iframe>';
url = '<object width="420" height="315"><param name="movie" value="http://www.youtube-nocookie.com/v/Ab25nviakcw?version=3&amp;hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube-nocookie.com/v/Ab25nviakcw?version=3&amp;hl=en_US" type="application/x-shockwave-flash" width="420" height="315" allowscriptaccess="always" allowfullscreen="true"></embed></object>';
url = 'http://i1.ytimg.com/vi/Ab25nviakcw/default.jpg';
url = 'https://www.youtube.com/watch?v=BGL22PTIOAM&feature=g-all-xit';
url = 'BGL22PTIOAM';
url = 'https://www.youtube-nocookie.com/embed//5ybGYHlgNGo';
*/