So i've researched a bit, and it looks like you can decode a .torrent file :$
<?php
include 'functions.php';
$torrent_data = bdec(file_get_contents('test.torrent'));
$info=strtolower(sha1(benc($torrent_data['info'])));
$scrape=str_replace('announce','scrape',$torrent_data['announce']);
$sources=bdec(@file_get_contents($scrape.'?info_hash='.urlencode(hex2bin($info))));
$c=count($torrent_data['info']['files']);
echo '<h2>Files</h2>';
$files=array();
if($c > 1)
{
for ($i = 0; $i < $c; $i++) $files[]=$torrent_data['info']['files'][$i]['path']['1'];
sort($files);
foreach($files as $file) echo $file."<br>";
}
else echo $torrent_data['info']['name']."<br>";
$seeds = $sources['files'][hex2bin($info)]['complete'];
$leechs = $sources['files'][hex2bin($info)]['incomplete'];
$downloads = $sources['files'][hex2bin($info)]['downloaded'];
echo '<h2>Sources</h2>'.
'<b>Seeds:</b> '.$seeds.'<br/>'.
'<b>Leechs:</b> '.$leechs.'<br/>' .
'<b>Downloads:</b> '.$downloads.'<br/>';
?>
To use this code you first need to include a file with the benc, bdec and hex2bin functions. You can get these functions from Here
I have prepared a testcase, which can be found Here
Hope this helped.