DigiKam 7.9.0 reads ctime instead of mtime, if file contains no metadata

[Peter Albrecht]

Hello list,

I updated digiKam from 7.1.0-2 (Debian 11) to 7.9.0-1+b2 (Debian 12) and now I 
experience a difference about timestamps read from files.
Importing a picture (or audio file or video file), which does not contain a 
timestamp in EXIF, to digiKam...
... old digiKam 7.1.0 did take the files "modification timestamp" (mtime).
... new digiKam 7.9.0 now takes the files "change timestamp" (ctime).

Why is this a problem for me?
I have some file in which I do not want to embed metadata like timestamps. To 
keep the information "when was this picture taken / video recorded", I write 
this information to the files modification time (mtime). It is not the best 
solution, but if you handle the file with care (e.g. using "cp -a"), you can 
manage to preserve this information.
You can't use change time (ctime) for this purpose, since it changes everytime 
you move or rename the file. And there is no easy way like "touch" to change the 
ctime.
So if digiKam reads the timestamp from a files "ctime", my information "when was 
this picture taken" will not be imported to the digikam database.

Do you have any idea, why this behaviour changed? Is there a way to configure 
digiKam, using the "mtime" again? Should I file a bug for this?

Thank you for reading,

Peter Albrecht

+++ My Settings:

[x]: means "checked / enabled"
[ ]: means "not checked / disabled"

Settings > Metadata > Behaviour
  [x] Timestamps
   ...
  [ ] Update file modification timestamp when files are modified
  [x] Rescan files when files are modified
  [ ] Clean up the metadata from the database when rescan files

Settings > Metadata > Sidecars
  [ ] Read from sidecar files
  [ ] Write to sidecar files

Settings > Metadata > Baloo
  [ ] Store metadata from digiKam in Baloo
  [ ] Read metadta from Baloo

Settings > Miscellaneous > Behaviour
  [x] Scan for new items at startup
     [ ] Fast scan
	

+++ Help > Components information

digikam version 7.9.0
Libraries:
XMP SDK: 5.6.0
Qt WebEngine version: 5.15.11
Qt: 5.15.8
Marble: 22.12.1
Libx265: 3.5+1-f0c1022b6
LibTIFF: 4.5.0
LibRaw: 0.21.0
LibPNG: 1.6.39
LibPGF: 7.21.07
LibOpenCV: 4.6.0
LibLCMS: 2140
LibJPEG: 62
LibHEIF: 1.13.0
LibGphoto2: 2.5.30
LibCImg: 130
LensFun: 0.3.3-0
KF5: 5.101.0
ImageMagick codecs: 6.9.11
Exiv2: 0.27.6
ExifTool: 12.57
Eigen: 3.4.0
DNG SDK: 1.5.1

Features:
VKontakte support: No
Rajce support: Yes
Parallelized demosaicing: Yes
Panorama support: Yes
Memory available: 31.3 GiB
Media player support: No
LibLqr support: Yes
LibJasper support: No
HTML Gallery support: Yes
HEIF writing support: Yes
HEIF reading support: Yes
Exiv2 supports XMP metadata: Yes
Exiv2 supports Base Media: Yes
Database backend: QSQLITE
DBus support: Yes
Calendar support: Yes
CPU cores: 12
Baloo support: Yes
AddressBook support: Yes