Bug 431081

Summary: Exif data is completely lost for some pictures after detect faces / recognize faces
Product: [Applications] digikam Reporter: michael.maier
Component: Faces-EngineAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: major CC: metzpinguin
Priority: NOR    
Version: 7.2.0   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: Version Fixed In: 7.2.0
Sentry Crash Report:

Description michael.maier 2021-01-02 20:37:53 UTC
SUMMARY

Exif data is completely lost for some pictures after detect faces / recognize faces on pictures already having face tags from Picasa

STEPS TO REPRODUCE
1. have some pictures with face tags from Picasa
2. select "Scan again and merge results" 
3. select "Detect faces" and scan for faces
4. select "recognize faces" and scan for faces
5. assign some face from unknown tag
6. repeat step 3 and step 4


OBSERVED RESULT
* some pictures (not touched with step 5) have lost their face tags from Picasa and also all other exif data.


EXPECTED RESULT
* exif data for pictures is not changed and data is not lost

SOFTWARE/OS VERSIONS
Digikam: Version 7.2.0-beta2

Windows: Win 10 home version 2004

KDE Frameworks 5.77.0
Qt 5.15.2 (built against 5.15.2)


ADDITIONAL INFORMATION
Comment 1 Maik Qualmann 2021-01-02 21:12:48 UTC
First, face detection and face recognition are read-only operation for images. There can be no change in the image here.
If you give a name to an unknown face, metadata will be written if this is activated in the metadata settings. Is this activated for you?
Give us a DebugView log as described here: https://www.digikam.org/contribute/

Maik
Comment 2 Maik Qualmann 2021-01-03 07:55:02 UTC
How do you conclude that EXIF metadata has been lost? In the digiKam Metadata view, an individual filter (filter button next to the search/filter input) can be set in each tab (EXIF, IPTC, XMP). Deactivate the filter to see all metadata. I cannot reproduce the problem here, as we have not yet had any feedback on such a problem, I think that there must be another cause with you.

Maik
Comment 3 michael.maier 2021-01-03 18:02:46 UTC
I did a little bit more investigation (should have done this before) and found that the face detection has no effect. It is some of the images which do not show item and photograph properties in the main window 
I have created a new bug 431121 for this.
please close this bug report