I'm not familiar enough with all the different terms, to know what is the best way to do it. Have you looked at the exiftool utility script that comes with Image-ExifTool? A quick lookthru at it's perldoc, seems to indicate that you can rewrite the IPTC Profile using certain fields only. You may have to save the current info and delete it out of the file, then process it, and rewrite it into the file. The exiftools script has a very nice perldoc with examples for doing almost everything. It's a bit too complex for me to delve into "just for fun". :-)