- base64_decode: documentation ( source)
<?php
echo base64_decode('UmV0dXJuIFBhdGggcsOpdW5pdCBsZXMgbGVhZGVycyDDoCBs4oCZb2NjYXNpb24gZGUgc29uIDFlciBSZXR1cm4gUGF0aCBXb3JsZCBUb3VyIFBhcmlz');
echo imap_mime_header_decode('=?utf-8?b?UmV0dXJuIFBhdGggcsOpdW5pdCBsZXMgbGVhZGVycyDDoCBs4oCZb2NjYXNpb24gZGUgc29uIDFlciBSZXR1cm4gUGF0aCBXb3JsZCBUb3VyIFBhcmlz?=');