Database / XMP discussion

["Bengt Thuree" <bengt thuree com>]

On Ti, 2006-10-24, 15:31, John Stowers skrev:

>
> One day, hopefully not toooooo far in future, I see f-spot using
> something like Tracker [1] as its database. For the moment however
> this is an implementation detail (understatement :-) ). What can be
> learnt from Tracker (and by extension the freedesktop metadata
> spec[2]/Exif/XMP) is the kind of information that can/should be stored
> to represent a photo.

Hi John

I do agree on the spirit of FreeDesktop, but am not quite sure I agree
with it fully. There are a number of standards for how to store metadata
in XMP format, and they are not duplicated (in general anyway, main
difference is the title/comment field). Why not use the standard
NameSpaces consisting of
* EXIF Data
* Dublin Core
* Iptc4XmpCore
Which is what F-Spot is doing for the moment.
If we start to use FreeDesktop namespace, then we would have to duplicate
the information since currently not many applications uses this one.

I do agree that F-Spot should store a lot of the existing tags that are
embedded in the photo. Mainly EXIF (Camera, Model, Flash, Size, Portrait
etc) related tags, but any others that F-Spot handles also of course.

This would enable F-Spot to do very fancy searches :)

One other option would be to use Beagles database (or interface) but
personally, I would rather Beagle would use F-Spot (if it existed) than
F-Spot beeing dependent on Beagle (which some people perhaps do not want
installed)

Version Database should probably have more information.
* Path to version (versions could be in different locations perhaps.)
* Version Created?  (A cropped photo's modified timestamp is probably
different from when it was imported, as well as different from when you
did minor touchup on it)

Having Rating as a tag should be workable (as we have stated in bugzilla),
but it would mean making some very special codes for it in the tag code.

On the other hand, we should enhance the tag code so we can ALWAYS (no
matter what language) find Location, City, Country, State etc to store
these tags in the proper XMP field (not tags). But then we also force the
user to have these special tags (which is not in current F-Spot idea)

This propably means that Tag database has to have three special fields.
* Visible (rating tag should not be visible
* Deletable (special tags should not be possible to delete)
* ID (So F-Spot can find it, irrelevant of language)

/Bengt

-- 
Bengt Thuree   bengt thuree com