queste righe di codiche stanno nel file /plugins/content/jw_sigpro/sigpro.engine.php
potrebbe essere il responsabile del problema?
// save the resized copy
$thumbname = $thbimgfolder.$prefix.substr(md5($srcimgfolder),1,10).$name;
switch($type) {
case 1:
if (function_exists('imagegif')) {
$success = imagegif($thumb, $site_absolutepath.$thumbname.'.gif');
$thumb_name = $prefix.$name.'.gif';
} else {
$success = imagejpeg($thumb, $site_absolutepath.$thumbname.'.jpg', $jpg_quality);
$thumb_name = $prefix.$name.'.jpg';
}
break;
case 2:
$success = imagejpeg($thumb, $site_absolutepath.$thumbname.'.jpg', $jpg_quality);
$thumb_name = $prefix.$name.'.jpg';
break;
case 3:
$success = imagepng($thumb, $site_absolutepath.$thumbname.'.png');
$thumb_name = $prefix.$name.'.png';
}
if ($success) {