mediaanalysisd high CPU on Mac? Here's what it actually does

mediaanalysisd is Apple's on-device computer-vision daemon: the engine behind Live Text (selecting text in images) and Visual Look Up. High CPU means it's analyzing media, the work is done locally on your Mac, and it normally finishes on its own. The most important thing to know: it is not the process that recognizes faces.

mediaanalysisd vs photoanalysisd: the distinction that matters

These two are constantly confused, and getting it right tells you what's actually happening:

• photoanalysisd is the Photos-library agent. Its role is background processing for the People album, Memories, and scene- or object-based search in Photos. That's where face recognition lives. (See photoanalysisd high CPU.)
• mediaanalysisd is the lower-level vision engine for Live Text, Visual Look Up, and text/object detection surfaced across the system, not tied to your Photos library.

So if you're worried about face scanning, that's photoanalysisd. mediaanalysisd reads text and looks up objects.

Why it's using high CPU

• After a macOS upgrade or importing lots of photos and videos, it re-analyzes media in the background.
• A rollout of Live Text or Visual Look Up can trigger a large one-time pass.
• It runs neural networks (on the Apple Neural Engine where available, or the CPU on older Macs), which shows up as CPU load while it works through a backlog. It's meant to defer while on battery.

Is mediaanalysisd a virus? Does it spy on me?

No on both counts. It's a genuine Apple daemon, and the vision work is on-device. Packet-level analysis has shown it doesn't upload your images; for Visual Look Up it sends only neural/perceptual hashes, and only when you tap to look something up. A 2023 "phoning home" scare was largely a misreading; the analysis is local.

What to do about it

1. Usually, wait it out. Keep the Mac awake and plugged in (leaving Photos open overnight helps) and it finishes, then idles.
2. Reduce the load by turning off Live Text and/or Look Up / Visual Look Up in System Settings if you don't use them.
3. Killing it only defers the work: it'll pick back up. For a genuinely stuck build, reboot or update macOS. If its cache has ballooned, clearing the com.apple.mediaanalysisd cache is a known fix.

Don't confuse the two

The one thing not to take away from this: mediaanalysisd does not do face recognition or scan your iCloud photos. Its background work is local, and faces/People are photoanalysisd's department.

Know which process, and whether it matters

Background AI work like this is normal but easy to panic over. Plumby puts live CPU in your menu bar with the process named plainly and the fix beside it, so you can tell routine on-device analysis from something that actually needs you, measured from your Mac's real state, with nothing about your files ever leaving the machine.