Difference between bx_timeline_photos table and bx_timeline_photos_processed table

Dear Developers,

May I know what is the difference between the tables in the bx_timeline_photos and bx_timeline_photos_processed? I have simulated an upload of a picture and noticed that the photo uploaded resulted into a new entry to these two tables, however the table photo2event only make use of the media id from bx_timeline_photos table. I proceeded to make a post and deleted the new entries from  bx_timeline_photos_processed table. I was still able to click on the image without any error. As I might be venturing into seeding events with photo on the timeline, I would like to know whether is it sufficient to seed just the bx_timeline_events, bx_timeline_photos and photo2event table and put in the image at the storage folder will do? Would bx_timeline_photos_processed  cause any issue if I skip the seeding on it? Is there anything else I need to take note for seeding events with images in this case, did I miss out any tables?