Because I only want to check for jpeg or png from a memory string, this is my 2 functions that are quick and don't have any dependencies :<?php function is_jpeg(&$pict) { return (bin2hex($pict[0]) == 'ff' && bin2hex($pict[1]) == 'd8'); } function is_png(&$pict) { return (bin2hex($pict[0]) == '89' && $pict[1] == 'P' && $pict[2] == 'N' && $pict[3] == 'G'); }?>