8     public function preFilter($html, $config, $context) {
 
    9         $pre_regex = 
'#<object[^>]+>.+?'.
 
   10             'http://www.youtube.com/((?:v|cp)/[A-Za-z0-9\-_=]+).+?</object>#s';
 
   11         $pre_replace = 
'<span class="youtube-embed">\1</span>';
 
   12         return preg_replace($pre_regex, $pre_replace, $html);
 
   16         $post_regex = 
'#<span class="youtube-embed">((?:v|cp)/[A-Za-z0-9\-_=]+)</span>#';
 
   17         return preg_replace_callback($post_regex, array($this, 
'postFilterCallback'), $html);
 
   21         return str_replace(
'--', 
'--', $url);
 
   26         return '<object width="425" height="350" type="application/x-shockwave-flash" '.
 
   27             'data="http://www.youtube.com/'.$url.
'">'.
 
   28             '<param name="movie" value="http://www.youtube.com/'.$url.
'"></param>'.
 
   30             '<embed src="http://www.youtube.com/'.$url.
'"'.
 
   31             'type="application/x-shockwave-flash"'.
 
   32             'wmode="transparent" width="425" height="350" />'.