Avoid duplicate value in list-tag object

[beedjees]

Hi,

I use this commandline to do a copy of the values from RegionPersonDisplayName to xmp-dc:Subject :

Code Select Expand

exiftool -sep "," -overwrite_original -"xmp-dc:Subject+<${RegionPersonDisplayName@; s/(.*)/"Personnes\/"$1/}" "C:\test\Test_work.JPG"
But, if I execute this commandline two times (on the same picture), the values in tag "xmp-dc:Subject" are duplicate.
Each time I execute this commandline, values are inserted (so duplicate).

I think, I should use "NoDups", but I don't know how...

These commandlines don't work

Code Select Expand

exiftool -sep "," -overwrite_original -"xmp-dc:Subject+<${RegionPersonDisplayName@; s/(.*)/"Personnes\/"$1/; NoDups}" "C:\test\Test_work.JPG"
exiftool -sep "," -overwrite_original -"xmp-dc:Subject+<${RegionPersonDisplayName@; NoDups; s/(.*)/"Personnes\/"$1/}" "C:\test\Test_work.JPG"

Thanks for helping !

[StarGeek]

Using -api NoDups option is a better option, as the NoDups helper function only works on the tag it is embedded in. So when you use
${RegionPersonDisplayName;NoDups}
it only affects any duplicates currently in RegionPersonDisplayName and doesn't removed dupes from the target Subject

You also have to recopy the Subject tag so exiftool gets the full list of items to remove duplicates from. You also have to move the + sign to change this
-xmp-dc:Subject+<${RegionPersonDisplayName...
into this
-+xmp-dc:Subject<${RegionPersonDisplayName...

Example. Your command is run twice, showing that duplicates are added. Then the command that re-adds the Subject, adds the edited RegionPersonDisplayName again so there are now three copies of "Personnes/*" that are going to be added to Subject. Once that is all set up, the -api NoDups takes over and removes any duplicates from the final list to be copied into Subject

Code Select Expand

C:\>exiftool -G1 -a -s -Subject -RegionPersonDisplayName y:\!temp\Test4.jpg 
[XMP-MP]        RegionPersonDisplayName         : Indiana Jones, Marion Ravenwood

C:\>exiftool -sep "," -overwrite_original "-Subject+<${RegionPersonDisplayName@; s/(.*)/Personnes\/$1/}" y:\!temp\Test4.jpg 
    1 image files updated

C:\>exiftool -G1 -a -s -Subject -RegionPersonDisplayName y:\!temp\Test4.jpg 
[XMP-dc]        Subject                         : Personnes/Indiana Jones, Personnes/Marion Ravenwood
[XMP-MP]        RegionPersonDisplayName         : Indiana Jones, Marion Ravenwood

C:\>exiftool -sep "," -overwrite_original "-Subject+<${RegionPersonDisplayName@; s/(.*)/Personnes\/$1/}" y:\!temp\Test4.jpg 
    1 image files updated

C:\>exiftool -G1 -a -s -Subject -RegionPersonDisplayName y:\!temp\Test4.jpg 
[XMP-dc]        Subject                         : Personnes/Indiana Jones, Personnes/Marion Ravenwood, Personnes/Indiana Jones, Personnes/Marion Ravenwood
[XMP-MP]        RegionPersonDisplayName         : Indiana Jones, Marion Ravenwood

C:\>exiftool -sep "," -overwrite_original -api NoDups -TagsFromFile @ -Subject "-+xmp-dc:Subject<${RegionPersonDisplayName@; s/(.*)/Personnes\/$1/}" y:\!temp\Test4.jpg 
    1 image files updated

C:\>exiftool -G1 -a -s -Subject -RegionPersonDisplayName y:\!temp\Test4.jpg 
[XMP-dc]        Subject                         : Personnes/Indiana Jones, Personnes/Marion Ravenwood
[XMP-MP]        RegionPersonDisplayName         : Indiana Jones, Marion Ravenwood
See FAQ #17, List-type tags for other options that you can use to remove duplicates.

[beedjees]

Thanks a lot, it works fine !

Thanks to your explanations I understand why you use "-TagsFromFile @ -Subject" associated with "-+xmp-dc:Subject<..." : It's a smart idea !