First version of Invenio considered albums as a first-class citizen of a system while treating photos as a subrecord of an album limiting user’s ability to add extra metadata to single pictures or index/search them. Additionally, management issues came into play, when user wanted to place one photo in multiple albums the only way to achieve that was to upload it twice, therefore introducing high redundancy.
The goal of photo albums changes in Invenio 2 is to solve aforementioned issues, by extracting pictures from albums, creating new records out of them and translating them to JSON from previous marc21 format to gain even more flexibility.