Don't add large blobs of data, e.g. base64, to the graph as property values . This is one of the few anti-use-cases for graph databases.
Store the binary information somewhere, e.g. AWS S3 , and have a node representing that photo or video. That node contains the S3 URL as reference and potentially some meta-data as well (width, height, quality, codec).
Use relationships to amend information like tagging, comments, ownership and permissions.