When a base is integrated with google drive, are the data/attachments stored by Airtable, or are they stored by google?

I’m making a base that needs to have a good deal of photo and video, and I worry about hitting storage limits (not enough to warrant getting an enterprise plan, currently on pro).

If the files are stored on Airtable, does anyone know of an elegant way to do something similar (store base contents externally, but access via airtable)?