diff --git a/htdocs/includes/odtphp/odf.php b/htdocs/includes/odtphp/odf.php
index 98cdcf0a2fd..ce72014c17d 100644
--- a/htdocs/includes/odtphp/odf.php
+++ b/htdocs/includes/odtphp/odf.php
@@ -1022,6 +1022,8 @@ IMG;
 		$matches = array();
 		preg_match($searchreg, $this->contentXml, $matches);
 		$this->contentXml = preg_replace($searchreg, "", $this->contentXml);
-		return  $matches[1];
+		if ($matches)
+			return  $matches[1];
+		return "";
 	}
-}
\ No newline at end of file
+}