[Digikam-users] Writing metadata to image files

[Vlado Plaga]

Am Mon, 11 Jan 2010 08:12:51 +0100
schrieb Julien Narboux <jnarboux at narboux.fr>:

> spinsheet a écrit :

> > Will DigiKam
> > build a database file based on the embedded metadata?

Yes, if digiKam finds a new picture with metadata that data is
included. I sometimes even found it annoying, getting pictures from
"outside" that already have descriptions and thus suddenly having new
tags in my tag tree.

> > As I do not
> > want others to have write access to the images, will they be able
> > to create their own custom tags that only reside on their machine
> > and not in the images (I would imagine that this is true)?

Yes, each digiKam from a different user (or on a different system) can
have its own database. Either the others configure their digiKam to not
write tags to images, or you simply don't give them write access to the
image files.

> Unfortunately, other people will have to use the "Album/ Reread
> metadata From Images" action in their copy of DigiKam  each time you
> are updating the metadata...

I also find this annoying, since I'm using digiKam with two different
configurations (from Linux and Mac OS) for the same set of pictures. I
thought I'd just let the two digiKam versions have their own database
and "sync" them by importing from metadata written to the pictures, but
this does not work.

As Stibbons writes in feature request #173632:

"The problem here is when updating the picture with an external tool,
changes in iptc comment are not reflected in digikam database."

https://bugs.kde.org/show_bug.cgi?id=173632

There is an answer by Marcel Wiesweg explaining this behaviour:

"When detecting a change of modification date, only 'hard' information
is rescanned, that is file size, fingerprint, dimension, format, bit
depth and color model.
The rationale is that digikam gives priority to what is stored in its
database. If you edit photos with an external tool, you need to take
the extra step and run the sync-with-db tool."

I think an option "Re-read metadata when files are modified", possibly
with an additional "Picture metadata overrides database information"
would be very useful. After all a picture with a modified file date
could IMHO just be handled like a new file - but of course changing
digiKam's default behaviour now would be counter-productive. That's why
new options would be nice. I might file a feature request for this soon,
but will leave the suggestion on the mailing list for a few days first.