สอบถามเรื่องการ resize และ upload file ครับ มีปัญหาเกี่ยวกับนามสกุลที่เป็นตัวใหญ่ อัพแล้วภาพไม่โชว์ครับ

<?
function resize_photo($tmp,$newname,$folder,$new_width){	
		
			$newname = strtolower($newname);
			
			$arr_name = explode(".",$newname);
			
			$lastname = $arr_name[sizeof($arr_name)-1];
			
	//		$newname = time().".".$lastname;		
			$file = getimagesize($tmp);
			
		if ($file[1]>$new_width){
		
		//copy($tmp,"photo/".$newname);
		if ($lastname=="jpg" || $lastname=="jpeg"){	
			$file = getimagesize($tmp);
		$newwidth = $new_width;
		$newheight = round($newwidth*$file[1]/$file[0]);
		
		$newimage = imagecreatefromjpeg($tmp);
		$imagex = imagesx($newimage);
		$imagey = imagesy($newimage);
		$image_fin =imagecreatetruecolor($newwidth,$newheight);
		imagecopyresampled($image_fin,$newimage,0,0,0,0,$newwidth+1,$newheight+1,$imagex,$imagey);
		imagejpeg($image_fin,$folder."/".$newname);
		imagedestroy($newimage);
		imagedestroy($image_fin);
		}
		elseif ($lastname=="gif"){
			$file = getimagesize($tmp);
		$newwidth = $new_width;
		$newheight = round($newwidth*$file[1]/$file[0]);
		
		$newimage = imagecreatefromgif($tmp);
		$imagex = imagesx($newimage);
		$imagey = imagesy($newimage);
		$image_fin =imagecreatetruecolor($newwidth,$newheight);
		imagecopyresampled($image_fin,$newimage,0,0,0,0,$newwidth+1,$newheight+1,$imagex,$imagey);
		imagegif($image_fin,$folder."/".$newname);
		imagedestroy($newimage);
		imagedestroy($image_fin);
		}
				elseif ($lastname=="png" || $lastname=="PNG"){
			$file = getimagesize($tmp);
		$newwidth = $new_width;
		$newheight = round($newwidth*$file[1]/$file[0]);
		
		$newimage = imagecreatefrompng($tmp);
		$imagex = imagesx($newimage);
		$imagey = imagesy($newimage);
		$image_fin =imagecreatetruecolor($newwidth,$newheight);
		imagecopyresampled($image_fin,$newimage,0,0,0,0,$newwidth+1,$newheight+1,$imagex,$imagey);
		imagepng($image_fin,$folder."/".$newname);
		imagedestroy($newimage);
		imagedestroy($image_fin);
		}

		}else{
		move_uploaded_file($tmp,$folder."/".$newname);
		}
		
		return $newname;
}
?>