[Digikam-devel] Reread metadata from image removes rating

[Marcel Wiesweg]

> > I just noticed that "Reread metadata from image" removes the rating
> > assigned to an image, even though I don't store ratings in the image
> > metadata. Is this the desired behaviour? For me it was really surprising
> > to have lost all ratings for an album because I had to reread the
> > metadata to get the updated geo-localization information from the files.
> 
> Indeed, that's a bug. I will fix it.

For this we must decide what "reread" means for which group of metadata.

Tags are merged, only new keywords will be added to the database.

Other fields are replaced as a group: If one field is found, all are replaced 
in the db. This applies to the groups GPS data, copyright information, and 
photo metadata (make, model, exposure etc.).

Currently rating, width, height, creation and digitization date and 
orientation are unconditionally replaced.

Remaining fields are treated as single fields and will be replaced if found 
and not touched if not found.

To fix the problem here, rating will only be replaced if set in the metadata. 
Please check if other fields here should be treated differently as well.