function Resize($originalfile,$newfilename,$newW=800,$newH=600) {
set_time_limit(0);
$srcimage = imagecreatefromjpeg($originalfile);
$srcW = imagesx($srcimage);
$srcH = imagesy($srcimage);
$newimage = imagecreatetruecolor($newW-1,$newH-1);
ImageCopyResampled($newimage,$srcimage,0,0,0,0,$newW,$newH,$srcW,$srcH);
imagejpeg($newimage,$newfilename,100);
imagedestroy($newimage);
imagedestroy($srcimage);
}