[Digikam-devel] face in metadata

[tsaitgaist]

Hi,

The user mailing list might be a better place for this post, but the 3
main threads about face detection and recognition are on the devel
mailing list, this is why I also post it here.
I wanted to first summarize my impressions.
I used digikam 2.0.0 beta 4.0 on ubuntu using some PPA, which includes
the face feature.
Face detection/recognition was used on ~ 3000 real life pictures.

On one hand, face detection works quite well (I use 90% "Best but
slow"). The are 10% false positive mainly do to patterns (similar to
some eyes, a nose and a mouth). Maybe it could be avoided by taking more
into account the colors. Face are not detected when rotated (>25°), or
to small (sometimes frustating because they are quite clear). Face
detection works really great on baby (1-2 years old) faces.

On the other hand, face recognition did not work so well. < 10% where
recognized correctly or recognized. I don't know if it uses the average
of a tag or takes the closest result it already has, but I have 50
pictures of myself, and it is still not able to recognize me.
Same applies for faces with less confirmed results.
Often when unknown, the face is recognized as the on of an old person
(more complex face). I'm a bit disappointed but this is only beta and
I'm sure it will evolve rapidly within the next month/years.

The most important aspect I miss is that the face is in the database
only, and not in the pictures information. If the pictures are copied,
only the tag (face name) remains in the metadata. The face area is not
there anymore. This is also the case if the picture is copied. Evenmore,
forcing the rescan (the image is marked as scanned) will not find the
previous results (when modified by hand).
Also when the album/picture is moved using digikam, the face area
information is not bound to the new image location.
Could it be possible to store the face area with the name in the
metadata (XMP) ?
Should I open  wish ticket ?

Thanks,
Kevin