<?php

// it's for show result in ideone
$stdout = fopen('php://stdout', 'w');

function url_relative_to_absolute($baseUrl, $relativeUrl, $removeGet=true) {
   $url = rtrim($baseUrl, '/').'/'.ltrim($relativeUrl, '/');
   if($removeGet)
      $url = strtok($url, '?');
   return $url;
}

$res = url_relative_to_absolute(
	'http://e...content-available-to-author-only...e.com', 
	'/upload/produse/Blu-ray/BD-H6500.jpg?maxwidth=800&maxheight=800'
);

// it's for show result in ideone
fwrite($stdout, $res);