.config file - question to overriding tag properties

[herb]

Hello Phil,

at the moment I work with DarwinCore tags and one goal is to change some elements of a structure from a single-value tag to a listtype tag. To modify the DarwinCore.pm file was no problem.
(I checked the result of my changes/modfications with command: exiftool -listx -xmp:all -s -f).

But looking into your example .exiftool_config file I have seen that it should be possible to override tag properties.
Therefore I tried to reach my goal using only .exiftool_config file. But always without success.
The example I talk about is the CircleOfConfusion; but it modifies only the ValueConv and not the tag-type.

So my question is: Is it possible to e.g. change the tag-type from single-tag to listtype-tag with a userdefined tag in config file?
If yes, please give some hints how to start.
Thanks in advance.

Best regards
Herb 

[Phil Harvey]

Hi Herb,

Yes, this is possible by adding List => 'Bag', to an XMP tag definition (or 'Alt', or 'Seq', depending on what type of list you want).

However, it isn't a good idea to change the type of a standard tag because metadata utilities (including ExifTool) may have problems with this.  If any of the standard definitions are wrong, they should be fixed.

You should be creating used-defined custom tags if the standard tags don't satisfy your needs.

- Phil

[herb]

Hello Phil,

thanks for your quick reply, your comments and help.

I was close to your solution, but accidentally I used lower case values: List => 'seq' and List => 'bag'
In this case inside the output of "exiftool.exe -listx -xmp:all -s -f" I did not find the keywords "bag" and "seq" as flags of the modified tags and/or structure elements.

Best regards
Herb