Part of macOS
mediaanalysisdMedia analysis
○ Leave it
Finds faces, objects and text in photos and videos.
What it is
Analyses photos and videos on your Mac so you can search them by what’s in them.
Why it might be busy
After importing photos or videos, mostly while the Mac is idle or charging. Usually minutes to hours for a big library.
If you stop it
macOS starts it again straight away. Leave it.
The verdict
○ Leave it. Part of macOS, or something that starts again by itself. You never need to close these.
In Activity Monitor
mediaanalysisd
From Procession’s guide, in the words the app shows.