Adding photos automatically

Hi All! Brand new to the gallery and I've used it for about a week. This thing is sweet!

A coworker had an idea I am trying to figure out how to do. Basically there are a couple of directories full of webcam photos (taken every minute) and we would like to add about 1-2 photos per day from these directories - so take 1 of every 700 or 1400 images. I was planning on writing a PHP script to go and move the selected photos into an album, but didn't know how to get them from the directory into the gallery.

I found this message:

http://gallery.menalto.com/node/21920

In addition I was planning on having a cron job run this php script nightly to add the newest 1-2 photos, so the solution I do would need to be repeatable.

So my main questions are - Where should I be moving these files, what permission would they need, and how do I get the gallery to add just the newest files into an existing gallery?

Thanks!