Thumbnail cache size and rebuild
See how much disk space the library's thumbnails and video previews take, and rebuild them if they go wrong — the photos themselves are never touched.
The Caches pane can rebuild the cache because it is made from the photos and can always be made again; nothing outside the cache folder is touched.
The figures
- the total size of the cache;
- how much of it is image thumbnails;
- how much is video previews — poster frames and hover clips.
The figures are measured when the pane opens and say when; the refresh button measures again.
Rebuilding
Each kind has a Rebuild button. Pressing it asks first — the button turns into Rebuild now and Cancel, and goes back by itself after a few seconds:
- rebuilding image thumbnails deletes every photo thumbnail and makes them again. It takes minutes. Albums, tags, edits and the trash are not affected;
- rebuilding video previews deletes every poster and hover clip and makes them again. This is hours of FFmpeg work.
Rebuilding is not offered while a scan or another pass is running.
Authored changes
The last line counts the authored changes recorded — the log of every album, tag and edit made in this library. Unlike the cache, it is not made from the photos and cannot be rebuilt.