Smart Multi-Uploader and Thumbnail Creator from GIF/ JPEG/ PNG with PHP

$upload_image_limit = 5; // How many images you want to upload at once?
$upload_dir = ""; // default script location, use relative or absolute path
$enable_thumbnails = 1 ; // set 0 to disable thumbnail creation

##################### THUMBNAIL CREATER FROM GIF / JPG / PNG

function make_thumbnails($updir, $img){

$thumbnail_width = 80;
$thumbnail_height = 60;
$thumb_preword = "thumb_";

$arr_image_details = GetImageSize("$updir"."$img");
$original_width = $arr_image_details[0];
$original_height = $arr_image_details[1];

if( $original_width > $original_height ){
$new_width = $thumbnail_width;
$new_height = intval($original_height*$new_width/$original_width);
} else {
$new_height = $thumbnail_height;
$new_width = intval($original_width*$new_height/$original_height);
}

$dest_x = intval(($thumbnail_width - $new_width) / 2);
$dest_y = intval(($thumbnail_height - $new_height) / 2);

if($arr_image_details[2]==1) { $imgt = "ImageGIF"; $imgcreatefrom = "ImageCreateFromGIF"; }
if($arr_image_details[2]==2) { $imgt = "ImageJPEG"; $imgcreatefrom = "ImageCreateFromJPEG"; }
if($arr_image_details[2]==3) { $imgt = "ImagePNG"; $imgcreatefrom = "ImageCreateFromPNG"; }

if( $imgt ) {
$old_image = $imgcreatefrom("$updir"."$img");
$new_image = imagecreatetruecolor($thumbnail_width, $thumbnail_height);
imageCopyResized($new_image,$old_image,$dest_x,
$dest_y,0,0,$new_width,$new_height,$original_width,$original_height);
$imgt($new_image,"$updir"."$thumb_preword"."$img");
}

}

################################# UPLOAD IMAGES

foreach($_FILES as $k => $v){

$img_type = "";

### $htmo .= "$k => $v

if( !$_FILES[$k]['error'] && preg_match("#^image/#i", $_FILES[$k]['type']) && $_FILES[$k]['size'] < 1000000){

$img_type = ($_FILES[$k]['type'] == "image/jpeg") ? ".jpg" : $img_type ;
$img_type = ($_FILES[$k]['type'] == "image/gif") ? ".gif" : $img_type ;
$img_type = ($_FILES[$k]['type'] == "image/png") ? ".png" : $img_type ;

$img_rname = $_FILES[$k]['name'];
$img_path = $upload_dir.$img_rname;

copy( $_FILES[$k]['tmp_name'], $img_path );
if($enable_thumbnails) make_thumbnails($upload_dir, $img_rname);
$feedback .= "Image and thumbnail created $img_rname
";

}
}

############################### HTML FORM
while($i++ < $upload_image_limit){
$form_img .= 'Image '.$i.':
';
}

$htmo .= '

'.$feedback.'

';

echo $htmo;