diff --git a/apps/gallery/ajax/getCovers.php b/apps/gallery/ajax/getCovers.php
index d56bf6fa4b7e5ce3bec3b9ae0f774989cf80086b..ebda8d3e47ff2b369967cc1985c23b8035f209b1 100644
--- a/apps/gallery/ajax/getCovers.php
+++ b/apps/gallery/ajax/getCovers.php
@@ -61,6 +61,12 @@ while (($i = $result->fetchRow()) && $counter < $numOfItems) {
 
 header('Content-Type: image/png');
 
+$offset = 3600 * 24;
+// calc the string in GMT not localtime and add the offset
+header("Expires: " . gmdate("D, d M Y H:i:s", time() + $offset) . " GMT");
+header('Cache-Control: max-age=3600, must-revalidate');
+header('Pragma: public');
+
 imagepng($targetImg);
 imagedestroy($targetImg);
 ?>