/**
* Return an XML string describing the DjVu image
- * @return string
+ * @return string|bool
*/
function retrieveMetaData() {
global $wgDjvuToXML, $wgDjvuDump, $wgDjvuTxt;
wfProfileIn( __METHOD__ );
+ if ( !$this->isValid() ) {
+ return false;
+ }
+
if ( isset( $wgDjvuDump ) ) {
# djvudump is faster as of version 3.5
# http://sourceforge.net/tracker/index.php?func=detail&aid=1704049&group_id=32953&atid=406583