Copying data from extended tag (catalognumber) to custom tag (CATALOG)

[ohrenkino]

See the FAQs how to copy one field to another:

Actions and batch-operations

How to copy one field value to another field? Example how to copy the content of the ARTIST field to the ALBUMARTIST field: Create a new action in an existing action group or make a new action group. Action type: Format value Field: ALBUMARTIST Format string: %artist% Note: If you want to copy all possible values of a field (in case you have multiple artist fields), the internal scripting function $meta_sep can be used in the format string, e.g., $meta_sep(artist,\\\\)

The mapping is only a good way if you want to write a special field to a special kind of tags, e.g. like FLAC tags.