Hello/Hi/Greetings,

trying to upload a video from ios using piwigo app, I get an error during verification.
on the server log I get
Mar 26 01:34:00 sacrum httpd: PHP Notice:  Undefined variable: gpsExif in /html/plugins/ImageMagick_GPS/include/imagemagickgps.class.inc.php on line 42

the following fixes the issue to upload , not fully tested though if it prevents gps data in other situations, just it stop sending junk error in the json output that need the app:
                if ($conf['imagemagick_gps']['addAlwaysGpsData'] == false)
                {
                        /* Check for existing GPS position data */
+                        if (is_array($exif) )
+                        {
                        $gpsExif = array_intersect_key($exif, array_flip(array('GPSLatitudeRef', 'GPSLatitude', 'GPSLongitudeRef', 'GPSLongitude')));
                        if (count($gpsExif) == 4)
                        {
                                return $exif;
                        }
+                        }
                }


    Piwigo 2.9.4
    OS: Linux
    PHP: 7.0.33 (Montrer les informations) [2019-03-26 01:46:49]
    MySQL: 5.1.73 [2019-03-26 01:46:49]
    External ImageMagick 6.7.2-7