[Digikam-devel] libkface

[Tobias Leupold]

Gilles,

I have a few comments on
https://projects.kde.org/projects/extragear/libs/libkface/repository/revisions/master/entry/DESIGN

> Faces database file is hosted in home directory to be shared with all
> applications which use libkface :

I don't think that's always the case; at least the recognize program in test/ 
does not use this path, but the current work dir to store the db.

And speaking generally of test/:

The recognize tool works fine. As said, I was able to implement face detection 
using libkface with a few lines of code after having had a look at the 
sources.

But I had to change all calls of kDebug() to qDebug(); kDebug() didn't produce 
any output here (im very new to programming C++/Qt/KDE, so perhaps, this is my 
fault; but it's quite confusing if the program doesn't speak). Same for the 
recognize program.

> KFaceGui is a simple application able to run detection and recognition
> without to use CLI. Currently detection is implemented and recognition is
> broken.

The GUI in test/gui/ is (in contrast to the code in test/) not compiled when 
building libkface. I think it would be nice if at least a README would be 
placed here with how to do it. It would also ne nice if recognition was fixed 
here, so that on has an example of how to do it.

And ... what's the general state of the library? When I tried to use it, I 
thought it's ready-to-use ...

The face detection works fine, but does it work better than using OpenCV's 
CascadeClassifier directly (cf. the small Python program I posted in 
https://bugs.kde.org/show_bug.cgi?id=292900 )? Where's the difference? I think 
this should be documented, as you surely put some effort into this, and 
there's some good reason to use libkface.

And what about the recognition feature? Just speaking for me, I wasn't able to 
use it yet. What about the align and preprocess tools? What do I have to do to 
be able to use it?

I thought of the library like "give it some faces to learn" and "give it the 
face part of a photo, get a person suggestion". Is this "high-level" access 
possible? It would be really fine if the library cared about alignment and 
preprocessing so nothing can go wrong.

I would really like to use it or even contribute to this library. There's 
surely a need for a good OSS face detection and recognition tool. I think 
everything would be way easier if all that was documented somewhere. Like some 
"This is what we have right now and this is what we can do with it". With some 
minimalistic clear and working example code.

At the moment, apart from the detection feature, It's quite hard to know 
what's going on and how to use it ...

Yours, Tobias