Bug 435351

Summary: What is the database table KDTree
Product: [Applications] digikam Reporter: Thomas Bach <Thomas.bach>
Component: Faces-WorkflowAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: caulier.gilles, metzpinguin
Priority: NOR    
Version First Reported In: 7.3.0   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: Version Fixed/Implemented In: 7.3.0
Sentry Crash Report:

Description Thomas Bach 2021-04-04 17:27:50 UTC
Im playim with the actual version to recognitaion faces. My Databes is setup to Mariadb 10. I have splitted the datebases to different names. After checkig the picures for new faces, i get no entries in the db KDTree. For me, it is a problem to understand, for what the different sql databaseses are working on
Comment 1 caulier.gilles 2021-04-04 18:03:12 UTC
KD-Tree is a vector space partionning:

https://en.wikipedia.org/wiki/K-d_tree

It used with face recognition to support clustering for speed up auto tagging with group of faces: 

https://ui.adsabs.harvard.edu/abs/2015SPIE.9631E..1IW/abstract

Gilles Caulier
Comment 2 caulier.gilles 2021-04-04 18:05:59 UTC
This paper explain in details clustering technique for face recognition :

https://arxiv.org/pdf/1604.00989.pdf

Gilles Caulier
Comment 3 Maik Qualmann 2021-04-04 18:18:20 UTC
The KDTree table is currently unused because we are creating one in RAM for speed reasons. The possibility of creating them in the database is optionally available in the source code.
This means that there is a possibility that we will use the table in the DB in the future.

Maik
Comment 4 Maik Qualmann 2021-04-04 19:27:13 UTC
I think it's all explained.

Maik
Comment 5 Thomas Bach 2021-04-05 08:21:27 UTC
Tx