[Digikam-devel] What do we want to store in the database?

[Arnd Baecker]

On Thu, 30 Aug 2007, Julien Narboux wrote:

> Hi,
>
> Maybe it would be easier to write this list on a wiki ?

Marcel already started a wiki some time ago
http://wiki.kde.org/tiki-index.php?page=Digikam+development+discussion

Marcel, should we add all the thoughts there as well
(including comments ?)

> Here are some other field which may be useful:

> - quantity of blur : maybe this fonctionnality could be added in the
> future, there exists some algorithm to measure blur. It would be nice to
> have it to compare a bunch a picture and eliminate those which are out
> of focused

This is an interesting idea (funnily, I thought about this
recently as well ;-): There is on "problem": sometimes
only a small region (e.g. a flower, insect, ...) of an image
is sharp and all  the rest will be blurred.
This one get a large value for blur, while it still
might be a perfect 5-star shot. So essentially
a local blur indicator might be needed.
This would require some interestings tests on algorithms ...
Do you have already some reference to the algorithms to
measure blur?

((To me this example just highlights that it would be nice
to allow for easy additions of new fields in the
database in the future, i.e. withouth the need to wait for
a 0.9 to 0.10 transition ...))


> >
> >     - orientation
> >
> >
> > ==> as the same value  than Exif orientation flag
> >
> > B.K.O about to find image by photo info is :
> > http://bugs.kde.org/show_bug.cgi?id=146337
> >
> >     - GPS:
> >     - latitude
> >     - longitude
> >     - altitude
> >
> >
> - tilt (nb of degrees with regard to horizontal)
> - orientation (compass)

Yes, this would be nice (Though I am not 100% sure, if this
has to be searchable?)
Additional remark:
This is useful for the KML 2.2 Photoverlay,
to precisely specify the region to which the photo
corresponds to, see
http://code.google.com/apis/kml/documentation/kml_tags_beta1.html#photooverlay
http://code.google.com/apis/kml/documentation/photos.html
http://www.gearthblog.com/blog/archives/2007/08/new_photo_viewer_wit.html

Also, this is of interest in the context of
gipfel, http://www.ecademix.com/JohannesHofmann/gipfel.htmlexternal link
which allows for finding the names of mountains
or points of interest on a picture.
(This uses: View direction, Nick angle, Tilt angle, Focal Length,
Visibility)

> Gilles wrote:
> > + GPS position description as string. My GPS device (Tom Tom one)
> > generate a GPX file with this informations for each point in trace. I
> > will improve GPSSync plugin to extract this srtings, this can be usefull.

What additional information is provided in the strings?

Best, Arnd