The Enhanced Visual Search feature of macOS Sequoia lets you search your photo library for landmarks or points of interest in photos or videos — making it easier to find what you’re looking for, even if those photos and videos don’t have any saved geolocation information.
The Enhanced Visual Search in the Photos app sends encrypted, anonymized data from photos to Apple. Here’s how this works, in Apple’s words: “First, an on-device machine learning model determines whether a photo or video in your library is likely to contain a landmark or point of interest. Then it creates a low-fidelity mathematical representation of the part of that photo that might contain the landmark, called an embedding. This embedding — not image data — is encrypted and sent to Apple servers, where it’s compared against a global list of landmarks and places that’s too big to fit on your device.”
However, you can turn it off if you wish. Here’s how on a Mac:
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° Launch the Photos app.
° From the menu bar, choose Photos > Settings > General.
° Select or unselect Enhanced Visual Search.