Is there a Jotform feature where digital stamps can be added to uploaded documents?

I'm looking into various ways to digitally approve posters on our College Campus. What are Jotform's capabilities in doing this? Thanks!

That's not possible if you want the digital tamp to be within the uploaded document, but you can do that when you download the uploaded files collected by your form and apply the digital tamp.

In case you want to add a digital stamp on the collected data, you do that by editing your PDF Document. Guide: https://www.jotform.com/products/pdf-editor/

On a side note, you can collect digital signatures too, check out these widgets https://widgets.jotform.com/search/signature

Great! I would like to add a stamp to uploaded files. I've tried playing around with PDF Editor for this but I can't figure it out. Is there a manual for how to use this feature? Thanks! 

As my colleague said, you can't add a stamp to uploaded files which are uploaded by user/applicant/etc. But you can add 'E-Signature' field to form for signing form by user/applicant/etc.

Also, you can create a PDF document for form. Then add a field as a stamp. You can attach this PDF to notification email. Please look at these images to clarify it.
You can create PDF document from here:

Select your title and layout:

I selected image field as stamp area.

Upload your stamp.

Your attachment PDF will look like that:

Please feel free to ask anything.