We can not fetch videos from this type of page.
Your URL was: http://loop.php?v=ko4k_Ya4n6w
http://loop.php?v=ko4k_Ya4n6w
The URL must be like http://www.youtube.com/watch?v=KPtX7hak0Qs
http://www.youtube.com/watch?v=KPtX7hak0Qs
https://www.
pwn
Example: