RegExp YouTube video iFrame | object

RegExp YouTube video iFrame | object

$regexstr = '~
# Match Youtube link and embed code
(?:				 # Group to match embed codes
   (?:<iframe [^>]*src=")?	 # If iframe match up to first quote of src
   |(?:				 # Group to match if older embed
      (?:<object .*>)?		 # Match opening Object tag
      (?:<param .*</param>)*     # Match all param tags
      (?:<embed [^>]*src=")?     # Match embed tag to the first quote of src
   )?				 # End older embed code group
)?				 # End embed code groups
(?:				 # Group youtube url
   https?:\/\/		         # Either http or https
   (?:[\w]+\.)*		         # Optional subdomains
   (?:               	         # Group host alternatives.
       youtu\.be/      	         # Either youtu.be,
       | youtube\.com		 # or youtube.com 
       | youtube-nocookie\.com	 # or youtube-nocookie.com
   )				 # End Host Group
   (?:\S*[^\w\-\s])?       	 # Extra stuff up to VIDEO_ID
   ([\w\-]{11})		         # $1: VIDEO_ID is numeric
   [^\s]*			 # Not a space
)				 # End group
"?				 # Match end quote if part of src
(?:[^>]*>)?			 # Match any extra stuff up to close brace
(?:				 # Group to match last embed code
   </iframe>		         # Match the end of the iframe	
   |</embed></object>	         # or Match the end of the older embed
)?				 # End Group of last bit of embed code
~ix';