I recently noticed that free users have access to collections now as well. After a first review, I wasn't all that excited to manually edit potentially hundreds of collections. So I thought it can't be that hard to automatically fetch the needed information from TheMovieDB. I realize a lot of people probably have updated their collections already, but maybe this will be helpful to someone else. Right now, only the python script exists, so you'll need a python/dev environment to execute.

TMDB Collection Data Retriever

How does it work?

The script collects all collections from your movie library that do not have a summary yet. It then checks the movies within the collection to find if these movies belong to a TheMovieDB collection. If a valid collection can be found it will pull the summary as well as download posters/background images (and use the same web calls as if you were manually updating it over the web interface).

A sample on a small test library looks like this:

Image may be NSFW.
Clik here to view.

Attention

Currently this has only been tested with a couple of libraries, so I would recommend doing a database backup before starting the process (even though I don't think the script can do any real harm).

All images will be fully downloaded, this might increase the size of your metadata folder significantly if you have a lot of collections.