Image upload security - reprocess with GD

Question

I\'ve heard that the best way to handle uploaded images is to \"re-process\" them using the GD library and save the processed image. see: PHP image upload secu

Answer 1

function isvalidjpeg($file) 
{ 
$finfo = finfo_open(FILEINFO_MIME_TYPE);
return is_resource($finfo) && 
       (finfo_file($finfo, $file) === 'image/jpeg') && 
       finfo_close($finfo);
}
if(isvalidjpeg($_FILES['file']['tmp_name'])) {
   $newIm = @imagecreatefromjpeg($_FILES['file']['tmp_name']); .....