ขอแนะนำเรื่องการใช้ function resize image ก่อน upload image ครับ

<?php

function resize_image($file, $w, $h, $crop=FALSE) {
    list($width, $height) = getimagesize($file);
    $r = $width / $height;
    if ($crop) {
        if ($width > $height) {
            $width = ceil($width-($width*abs($r-$w/$h)));
        } else {
            $height = ceil($height-($height*abs($r-$w/$h)));
        }
        $newwidth = $w;
        $newheight = $h;
    } else {
        if ($w/$h > $r) {
            $newwidth = $h*$r;
            $newheight = $h;
        } else {
            $newheight = $w/$r;
            $newwidth = $w;
        }
    }
    $src = imagecreatefromjpeg($file);
    $dst = imagecreatetruecolor($newwidth, $newheight);
    imagecopyresampled($dst, $src, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

    return $dst;
}

if (isset($_FILES['upload']['name']) && isset($_FILES['upload']['tmp_name'])){
	$tmp_name = $_FILES['upload']['tmp_name'];
	$name = $_FILES['upload']['name'];
	
	if (!empty($name) && !empty($tmp_name)) {
		resize_image($tmp_name, 100, 100);
		$path = 'gallery/';
		if (move_uploaded_file(resize_image($tmp_name, 200, 200, $crop=TRUE), $path.$name)) {
			echo 'ok.';
		}
	} else {
                echo 'empty image.';
        }	
} 
?>