A simple module for Gallery 3 which uses exiftool to write changed metadata into JPG files.

There are a number of huge caveats:

1. It's not particularly well tested. It may eat all of your files.
2. Requires exiftool, and furthermore is hardcoded to look for /usr/bin/exiftool -- that should be an option.
3. Only handles Title and Description.
4. A little slow.

On the plus side:

1. It seems to work for me.
2. Tries to avoid changing things which don't need changing.
3. It does rudimentary error checking and should at least log if it's broken something.