[Digikam-users] [KPhotoAlbum] User experience (or bugs, hopes and wishes)
caulier.gilles at kdemail.net
Mon Oct 2 13:07:51 BST 2006
On Monday 02 October 2006 13:58, Robert L Krawitz wrote:
> Date: Mon, 02 Oct 2006 19:58:22 +0900
> From: "Birkir A. Barkarson" <birkirb at stoicviking.net>
> This is my first posting to the mailing list. It is mainly intended
> for the Digikam mailing list as that is what I am currently using
> but I cross post this to the KPhotoAlbum list as well since I like
> their interface and it is my hope that they will adopt similar way
> to store metadata in-tag like digikam does. My apologies if this
> is offends or is not welcomed.
> Just to be fair, there are also disadvantages to storing metadata in
> the images:
> 1) Any time the original image files are modified there's a risk of
> corrupting them.
> 2) It doesn't work if the images are physically stored on a read-only
> 3) Updating many images is likely to be very slow (the image file will
> likely have to be resized to add or remove metadata, which will
> result in the entire file having to be rewritten). For example, I
> tagged 3500 images totaling 25 GB from a recent vacation.
This is not true about JPEG. Only JFIF, EXIF and IPTC section are rewritten.
The image data are untouched.
Later, i will implement in Exiv2 the same thing about PNG to write metadata on
the fly without decoding/encoding image data. About TIFF, Andreas (Exiv2
coordinator) will implemente the TIFF-EP/RAW file metadata writting on the
fly using the same rules.
> 4) Some cameras can sign images to later verify that they have not
> been modified (e. g. for use as evidence in court). Depending upon
> exactly what the signature covers, modifying the image file may
> destroy the signature.
If sign is in metadata, well yes something can be lost. I suspect than
Makernotes are used for that. Since Exiv2 Makernotes support have been
improved with the last stable release, i think than this problem is now
If sign is a watermark embedded into image data, we don't change these data
during metatada update.
> 5) It's much harder to implement undo across sessions or versioning if
> the metadata is stored in the images.
> I actually rather like the database and "do not modify the original
> image file" myself, and it's a big reason why I use KPhotoAlbum.
In digiKam you has the choise : database only, database+pictures. Look in
metadata setup tab.
More information about the Digikam-users