(PHP 5, PHP 7)
stream_get_filters — Retrieve list of registered filters
Retrieve the list of registered filters on the running system.
Returns an indexed array containing the name of all stream filters available.
Example #1 Using stream_get_filters()
<?php
$streamlist = stream_get_filters();
print_r($streamlist);
?>
The above example will output something similar to:
Array ( [0] => string.rot13 [1] => string.toupper [2] => string.tolower [3] => string.base64 [4] => string.quoted-printable )