php จะทำการ resize ย่อรูปให้เล็กตามขนาดที่ต้องการ ทำไมบางทีขนาดมันใหญ่ขึ้นหว่า?

<?
$images = "images/Better Together.jpg";
$width=600;
$new_images = resize_img($images,$width);
?>


<b>Original Size</b><br>
<img src="<?=$images;?>" width="<?php echo $width; ?>">
<hr>
<b>New Resize</b><br>
<img src="<?=$new_images;?>">


<?php
function resize_img($images,$size){
	$temp = explode('/',$images);
	$re_temp = array_reverse($temp);
	$new_images = 'MyResize/rez_'.$re_temp[0];
	$width = $size;
	$size=GetimageSize($images);
	$height=round($width*$size[1]/$size[0]);
	
	unset($temp,$re_temp);
	$temp = explode('.',$images);
	$re_temp = array_reverse($temp);
	$dot = trim(strtolower($re_temp[0]));
	switch($dot){
		case 'jpg': $images_orig = imagecreatefromjpeg($images); break;
		case 'jpeg': $images_orig = imagecreatefromjpeg($images); break;
		case 'png': $images_orig = imagecreatefrompng($images); break;
		case 'gif': $images_orig = imagecreatefromgif($images); break;
	}//switch
	$photoX = ImagesX($images_orig);
	$photoY = ImagesY($images_orig);
	$images_fin = ImageCreateTrueColor($width, $height);
	ImageCopyResampled($images_fin, $images_orig, 0, 0, 0, 0, $width+1, $height+1, $photoX, $photoY);
	ImageJPEG($images_fin,$new_images);
	ImageDestroy($images_orig);
	ImageDestroy($images_fin);
	return($new_images);
}//resize_img
?>