Apple TV rotates screen saver photos
I have a ATV 4K and an iMac 4K, when using the ATV screen saver many photos are rotated 90 or 180 degrees. They are correct on the iMac. How do I correct this?
That sounds like a bug, where the image viewer/processor isn’t respecting the orientation tag in the EXIF data. In other words, it DOESN’T rotate the images that it should rotate.
It is common for smartphone cameras to take pictures with a fixed orientation, and adding a small piece of information telling which way is up (and mirroring). If viewing software doesn’t interpret that orientation tag (as intended), then you would see images as they were stored, not as they were taken.
1/ A good camera adds good tags. A bad tag might be invalid for some software.
2/ Software has to interpret the orientation. It might be that it ignores it or invalidates it.
3/ Photos or Preview may interpret differently than the Screen Saver, as each does its own checks.
Note that I can’t reproduce your experience with photos from my iPhone SE (iOS 11.3) in various orientations on the Apple TV 4K (tvOS 11.3).
Do your rotated images come from a specific camera or smart phone?
Did you set up the screen saver from My Photos (iCloud photo stream) or from Home Sharing (local folder)? (Not sure if it makes a difference, but it could be.)
Apparently it is difficult, as major image hosting sites, and major brand cameras, and major brand image software have put out versions that didn’t get this right.