using codeigniter _remap(); with persian characters

Question

im using _remap(); in my controller and trying to route the address like this

http://localhost/courses/سلامتی

but my $course value is =

%D8%B4%D8%B3%D8%B4%D8%B3%D8%B4%D8%B3%DB%8C%D8%B4%D8%B3%DB%8C%D8%B4%D8%B3%DB%8C

    public function _remap($slug) {
        $data['title'] = ucfirst("Blog");
        $data['course'] = $slug;

        parent::setTemplate('views/courses/view', $data);
    }

Answer 1

i found the answer
$data['course'] = $slug; should change to
$data['course'] = rawurldecode ($slug);