public function __construct($filename = null, $strict = false)
{
Helper::checkGD();
if (ctype_print($filename) && FS::isFile($filename)) {
$this->loadFile($filename);
} elseif (Helper::isGdRes($filename)) {
$this->loadResource($filename);
} elseif (is_string($filename) && $filename) {
$this->loadString($filename, $strict);
}
}