These messages showed on servers with PHP v5.3 or newer and 4images v1.7.7 or older.
There is nothing to worry about, as it is not errors, just warnings that meant to be for developers.
It will be fixed in 4images v1.7.8.
Until then the messages can be turned off by replacing in global.php
error_reporting(E_ERROR | E_WARNING | E_PARSE);
with this:
error_reporting(E_ERROR | E_WARNING | E_PARSE & ~E_DEPRECATED);
In search.php delete:
error_reporting(E_ALL);