gcan2pdf giving missing packages warning on startup

On starting gscan2pdf it gives these warnings

Warning: missing packages
Save image requires libtiff
PDF encryption requires pdftk

Although they are installed.

P.S. I can't set the tags, for some reason the modal box for that automatically fades

How did you install pdftk?

It's not installed since it's not in the repository. I think this is probably an issue in packaging.

I see. I get same message too.

I suggest you to report an issue here.
Also this package needs and update to 2.5.6.

Ok I am going to report this in the issue tracker. Kindly mark this as solved.