[Digikam-users] Microstock and IPTC

[Milan Knížek]

Leonardo Giordani píše v So 05. 09. 2009 v 19:28 +0200:
> Hi all,
> 
> since I'm trying to enter the microstock market I'would like to ask if
> someone of you has experience in this field (with digiKam of
> course :) ) and expecially if you can provide me some advice on IPTC
> tags. In particular:
> 
> 1. What tags are needed (or almost useful) and where to find them on
> digikam IPTC editor: for example I know that TITLE is a needed tag but
> I do not find it; the first tag I find is Content|Summary, and do not
> know if they are the same.
> 
You would have to check with Microstock what they mean by "TITLE". Most
probably "HeadLine" or "ObjectName"?

You can also have a look at IPTC web site, or directly at one of the
documents describing the tags:
http://www.iptc.org/std/photometadata/specification/IPTC-PhotoMetadata(200907)_1.pdf
(page 27 compares the tags with Photoshop XMP).

> 2. Is it possible to tag multiple images at once? For example I shoot
> 20 photos in the same location: if I select all the photos and try to
> edit IPTC tags I just get two additional "Previous" and "Next" button
> to navigate the list of selected images but cannot set all of them on
> the fly.
> 
Not yet in digiKam. I use MaPiVi to edit IPTC location for multiple
images at once (but do not touch other tags like keywords, caption, etc.
not to interfere with the way digiKam synchronises metadata).
> 3. Looking on microstock web sites I see that photos are also well
> categorized by content  with a taxonomy: for example see this Fotolia
> image http://www.fotolia.com/id/16535435 (a random one), where
> Representative Category is set to Landscape>Water>Lake/Pond and
> Conceptual Category to Leisure>Holiday>Tourism. Are those IPTC
> categories or Fotolia ones? In the first case how can I set them? In
> the IPTC editor I found a "Subject Information" tab, but the
> navigation through standard reference codes is not usable (too many
> codes, it is not hierarchical).
> 
I do not know here, but can guess: First, you need to find out if these
are "IPTC keywords" or "IPTC categories" tags. "IPTC categories" are
depreciated from the standard, so I guess these are keywords.

digiKam uses hierarchy in keywords (stored as Xmp.digiKam.TagsList and
synchronised to Xmp.lr.hierarchicalSubject for Lightroom compatibility).

However, IPTC standard does not define hierarchy for keywords and the
keywords are sync'ed to IPTC without hierarchy by digiKam. We could
consider it a bug, but some people may actually like it. (I do not
mind.)

You can test yourself in digiKam (edit caption, keywords, ratings, iptc
data manually) and quickly see all the tags (at the end of the list):

$ exiv2 -pa imagename.jpg | less

Since I store various information (incl. personal notes, which I do not
want to get published on the internet) in the metadata, before
publishing I use a bash script to re-organise the metadata to fit my
needs.

You could do the same: copying the hierarchy from XMP to IPTC keywords
and then deleting everything but IPTC. exiv2 or exiftool would be your
friends there.

I can imagine that in the future, digiKam could have an export plugin
allowing the user to define what information (a single branch in
keywords hierarchy, no ratings, etc.) should be exported and how (in
which standard).

regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)