den4b Forum

There are multiple ways of achieving this with different levels of complexity and nuances.

The easiest way is probably with the User Input rule, but it assumes the files between the two folders are mapped 1:1 exactly.

1. New renaming project, no rules.
2. Add files from the "full names" folder.
3. Sort by the Name column.
4. Export menu » Export new names to clipboard.
5. Remove all files.
6. Add files from the "short names" folder.
7. Sort by the Name column.
8. Add a User Input rule and paste the list of names from clipboard.

Depending on the number of those extra files, you could actually remove those extra files from the list to make that renaming plan work.

Alternatively, you can try something like this:

1. New renaming project, no rules.
2. Add files from the "full names" folder.
3. Add a rule to delete the extra part of the filename to match the short filenames.
4. Export menu » Export all columns to clipboard.
5. Open LibreOffice Calc (or Microsoft Excel), paste the contents from the clipboard.
6. Remove all columns except for "Name" and "New Name", which should correspond to full and short filenames.
7. Swap the two columns around so that the first column has short filenames and the second column has full filenames.
8. Save as a CSV file into your "short names" folder.
9. New renaming project, no rules, no files.
10. Export menu » Import file paths and new names.
11. Rename.

Soon there will be a new Mapping rule added to ReNamer which will simply this procedure.