Problem:

There are no photos in the albums in Discover in Gallery, or the portraits and objects in Discover cannot be identified or displayed. Only the locations are identified.

Solution:

Try charging your phone/tablet at night with the screen off until the battery level reaches over 50% to see whether the issue can be resolved. If not, perform the following steps:

1. On the Camera Settings screen, enable GPS tag/Location tag to allow photos to be tagged and sorted by location.
2. Ensure that Gallery includes some portraits which can be classified in the PEOPLE category.
3. Ensure that Gallery includes photos that can be classified in the THINGS category. This category includes photos of food, documents, modes of transport, animals, furnishings, electrical appliances, clothes, scenery, toys, art, festivals, and events.
4. Open Settings, search for and access Apps, and go to Gallery > Storage > CLEAR DATA. After you delete the gallery data, Gallery will access the data and analyze it again.
   

   Clearing Gallery data will not delete photos from Gallery, but will cause My favorites, Highlights, and Discover albums to disappear. Highlights and Discover albums will be automatically generated after the device is charged for a period of time with its screen off. My favorites albums will appear again after you add any photos to favorites. Customized categories of hidden albums in Gallery will be lost, and will then be moved to the Restore album.