Simple script to get the screenshot of a particular URL from youtube,

<script type="text/javascript">
function getScreen( url, size ) {
if(url === null){
return ""; } size = (size === null) ? "big" : size; var vid; var results;

 results = url.match("[\\?&]v=([^&#]*)");

 vid = ( results === null ) ? url : results[1];

 if(size == "small"){
 return "http://img.youtube.com/vi/"+vid+"/2.jpg"; }
 else {
 return "http://img.youtube.com/vi/"+vid+"/0.jpg"; }
 }

</script>

<?php  $url = "http://www.youtube.com/watch?v=hQVTIJBZook";
echo $url;
 ?>

<script type="text/javascript">

var imgUrlbig = getScreen("<?php echo $url ?>");
var imgUrlsmall = getScreen("<?php echo $url ?>", 'small');

document.write('<img src="' + imgUrlbig + '" />');
document.write('<img src="' + imgUrlsmall + '" />');

</script>

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