$file='../img/medaglie/10.gif';

$zip= new ZipArchive();

if(($zip->open('../tmp/test.zip', ZipArchive::CREATE))!==true){ die('Error: Unable to create zip file');}

$zip->addFile($file);

$zip->addFile($file,'newname.gif');

$zip->close();

echo "Sono stati zippati: " . $zip->numFiles . " file.\n";