While organizing my pictures I typically use many operations of exiftool to adjust date/time, rename the file, bulk add GPS locations, add creator names etc. In this process, each JPG image is typically renamed and their tags processed multiple times.
In this process I want to keep the original filename (without file extension), just like the camera/phone has written it. When running a bulk operation over a large number of files, there may be some of them still with their original filenames and others may already be renamed and have their original filename already set in the preserved filename tag.
Is there an exiftool command that sets the XMP preserved filename tag only on the first time, i.e. if the preserved filename tag is empty and otherwise leaves it untouched?