imagecopyresized() invalid image dimensions?

Bekomme ich die folgende Fehlermeldung, wenn Sie versuchen, erstellen Sie eine Miniaturansicht des Bildes:

Warning: imagecopyresized() [function.imagecopyresized]: Invalid image dimensions in H:\Programs\webserver\root\media\images\inc\func.php on line 160

Dies ist die Funktion die ich erstellt habe, um die Arbeit zu tun:

function create_thumbnail($image_type, $image_height, $image_height, $temp_dir, $thumb_path, $thumb_width, $thumb_height){
    switch($image_type){
        case 'image/jpeg';
            $img =      imagecreatefromjpeg($temp_dir);
            $thumb =    imagecreatetruecolor($thumb_width, $thumb_height);
                        imagecopyresized($thumb, $img, 0, 0, 0, 0, $thumb_width, $thumb_height, $image_width, $image_height);
                        imagejpeg($thumb, $thumb_path, 100);


        break;
        case 'image/png';
            $img =      imagecreatefrompng($temp_dir);
            $thumb =    imagecreatetruecolor($thumb_width, $thumb_height);
                        imagecopyresized($thumb, $img, 0, 0, 0, 0, $thumb_width, $thumb_height, $image_width, $image_height );
                        imagepng($thumb, $thumb_path, 100);

        break;
        case 'image/gif';
            $img =      imagecreatefromgif($temp_dir);
            $thumb =    imagecreatetruecolor($thumb_width, $thumb_height);
                        imagecopyresized($thumb, $img, 0, 0, 0, 0, $thumb_width, $thumb_height, $image_width, $image_height );
                        imagegif($thumb, $thumb_path, 100);

        break;
    }

}

Welches verwendet wird, etwa so:

//Create the new thumbnail dimensions
                        list($thumb_width, $thumb_height) = thumb_dimensions($case, $image_width, $image_height);

                        //Create the thumbnails
                        create_thumbnail($image_type, $image_height, $image_height, $temp_dir, $thumb_path, $thumb_width, $thumb_height);

Dem Daumen die Abmessungen sind Breite: 100px Höhe: 99px;