Update files from catalog and vice versa

[tonyt]

Please could someone tell me when I should use these two options and why?
Thanks

[tonyt]

Anyone help me?

[michel038]

Away from home for some days....
Update catalog from files makes xnviewmp read keywords in selected files and build or update a database used by categories filters. This feature uses "Tools, Settings, Metadata" import options. At the same place, "export" option makes xnviewmp write keywords when a category is checked ...

[michel038]

... and Update files from catalog can be used :
- if you forgot to use the "export categories ..." option when tagging
- if you want to create many types of keywords (iptc, xmp, xmp sidecar, xmp hierarchical) in photos where one type was missing.
- if you want to write ratings or color labels into metadata , if they were not.
- if you import XnView Classic database.

These two features are working only on selected photos.
If one wants to use them in all subfolders at once, right-click on the parent folder and choose "show all files, recursive"

[Pepelu]

I know this is an old post, but still, I need a little clarification.

What happens if I use Update files from Catalog to all my pictures? Will I get duplicated date either on the file or on the catalog? Will it do nothing to the files that are Ok in the catalog?

I guess I just want to know what does it do and how.

[michel038]

A clean start is as follows:
- Same informations are in the catalog and in metadata in the photos.
- You have added star ratings, categories, color labels, face tags in your photos in XnViewMP with export options enabled.
- You can see that each category assigned to an image corresponds to a keyword stored in the metadata (XMP, IPTC, Sidecar, depending on your settings)

Then

If you have tagged photos with other softwares, you can update the catalog : use "Update catalog from files" (Import options must be enabled)
If your catalog was damaged, you can update it with the same command.

If your catalog is in good condition, and you have edited or modified photos or their metadata outside XnViewMP, you may wish to restore the keywords, ratings, color labels to their original state into the photos : use "Update files from catalog " with export options.
If you've categorised, rated .. your photos with XnViewMP and forgotten the export options, use also "Update files from catalog "
This will write existing data from the catalog to the metadata embedded in the photos.
I think it will also erase metadata if the photo is described in the catalog with empty metadata.

Other metadata (Dates, Caption, Title, City, Country ...) are not affected by these operations, and are not included in the catalog.

[Pepelu]

Thanks a lot, I think I get it.