imagecopymerge problems?

[Sim]

I'm trying to take an image and extract every 32x32 image from it. heres what I got. every image i upload is divisible by 32 so I know thats not the problem. ever image I uploaded gets created as preview.png so i know thats not the problem either.

 

			mkdir("../tiles/$names", 0777);
		$file_typ = array();
		$file_typ =  explode('.',strtolower($_FILES["file"]["name"]));
		$file_type = $file_typ[count($file_typ)-1];
		if($file_type == "png")
		{
			move_uploaded_file($_FILES["file"]["tmp_name"], "../tiles/$names/preview.png");
			$src = imagecreatefrompng("../tiles/$names/preview.png");

			$w = imagesx($src) / 32; 
			$h = imagesy($src) / 32;
			if( (is_int($w)) && (is_int($h)) )
			{

				 /* Create a blank image */
				for($x=0; $x < $h - 32; $x=$x+32)
				{
					for($y=0; $y < $w - 32; $y=$y+32)
					{
						$im  = imagecreate(32, 32);
						imagecopymerge($im $src, 0, 0, $x,$y, $x+32, $y + 32, 0);
						imagepng($im ,"../tiles/$names/$x-$y.png"); 
					}
				}
			}
		}