<?php
....
// preg_match yöntemiyle
preg_match('#"file", encodeURIComponent\("(.*?)"#si',$video_data,$find);
echo $find[1]; // youtube flv
preg_match('#"image", "(.*?)"#si',$video_data,$find2);    
echo $find2[1]; // youtube img

//Explode yöntemiyle
$yakala = explode('"file", encodeURIComponent("', $video_data);
$yakala = explode('"', $yakala[1]);
echo $yakala[0]; // youtube flv
...
?>