What do you need to know? You example works uploading a file. You just need to write it to a file. So instead of doing a print to the browser (which would just show the data of the image not the actual image) just write it to a file.

Just check to make sure it's an image and write it to a binmode'ed file handle.

Untested Code:

     my $filename = $cgi->param('uploaded_file');
     my $type = $cgi->uploadInfo($filename)->{'Content-Type'};

     #use the upload function
     if ($type eq 'image/jpeg') {
       open(IMAGE,">/image_dir/filename.jpg");
       my $fh = $cgi->upload('uploaded_file');
       binmode(IMAGE);
       while (<$fh>) {
           print IMAGE $_;
       }
       print '<img src="/image_dir/filename.jpg">';
     } else {
       print 'Not a JPEG<br>';
     }
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