[Digikam-users] DigiKam and ACDSee

[Alan Pater]

Hi again all

I've gone ahead and documented how various applications implement
hierarchical keywords/tags. In each application I created the same 6
level hierarchy and tagged a sample image with level 2 and level 5. I
then used exiv2 to read the resulting metadata. These are just the
main hierarchical fields written, flat tags are also in
xmp.dc.subject, for example.

    6 Level
(X)     6.2 Level
            6.3 Level
                6.4 Level
(X)                 6.5 Level
                        6.6 Level


* Digikam 4.8
Xmp.digiKam.TagsList        XmpSeq  2  6 Level/6.2 Level/6.3 Level/6.4
Level/6.5 Level, 6 Level/6.2 Level

* Adobe Lightroom 4.4
Xmp.lr.hierarchicalSubject  XmpBag  2  6 Level|6.2 Level, 6 Level|6.2
Level|6.3 Level|6.4 Level|6.5 Level

* ACDSee 8 Pro
Xmp.acdsee.categories   XmpText   282   <Categories><Category
Assigned="0">6 Level<Category Assigned="1">6.2 Level<Category
Assigned="0">6.3 Level<Category Assigned="0">6.4 Level<Category
Assigned="1">6.5
Level</Category></Category></Category></Category></Category></Categories>

** Metadata Working Group Keywords
Xmp.mwg-kw.Keywords
     XmpText     0  type="Struct"
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy
     XmpText     0  type="Bag"
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]
     XmpText     0  type="Struct"
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Keyword
     XmpText     3  6 Level
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Applied
     Boolean     1  0
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Children
     XmpText     0  type="Bag"
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Children[1]
     XmpText     0  type="Struct"
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Children[1]/mwg-kw:Keyword
  XmpText     7  6.2 Level
Xmp.mwg-kw.Keywords/mwg-kw:Hierarchy[1]/mwg-kw:Children[1]/mwg-kw:Applied
  Boolean     1   1
etc
etc
etc, nested deeper and deeper ...


  I am still working on the mwg-kw structure. It is much more complex
then any of the others, which explains why it is so little used! It
was written using my patch to exiv2 http://dev.exiv2.org/issues/1040

Alan