Bug 421521

Summary:	Wrong EXIF photograph properties shown when there is no EXIF data at all
Product:	[Applications] digikam	Reporter:	andrej.valencic
Component:	Metadata-Exif	Assignee:	Digikam Developers <digikam-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	minor	CC:	caulier.gilles, metzpinguin
Priority:	NOR
Version First Reported In:	7.0.0
Target Milestone:	---
Platform:	Microsoft Windows
OS:	Microsoft Windows
Latest Commit:		Version Fixed/Implemented In:	7.0.0
Sentry Crash Report:
Attachments:	DK screenshot Offending photo EXIF info

Description andrej.valencic 2020-05-14 17:11:38 UTC

SUMMARY
In the right sidebar there are wrong EXIF info in the Properties section.

STEPS TO REPRODUCE
1. Chose a photo
2. Properties sidebar
3. Photograph Properties is wrong

OBSERVED RESULT
I've received some photos from my friend and copied them to my library (I guess my friend removed some or all of the EXIF info from them). But after DK finds this new items, the properties shown are wrong - do not mirror EXIF data of the photo. For example the Make and Model are from my phone not the camera that was actually used. Also other properties like Focal, Aperture and so on are wrong - and exactly the same for all these photos. Then I've checked the EXIF data of these photos and couldn't find why the properties are shown like this - don't know where DK gets this from.

EXPECTED RESULT
If the expected EXIF data is not found, empty fields or 'unknown' should be shown in the Properties sidebar.

SOFTWARE/OS VERSIONS
Windows 10: Build date: May 12 2020 (target: RelWithDebInfo)
KDE Frameworks Version: 5.70.0
Qt Version: 5.14.2 (built against 5.14.2)

ADDITIONAL INFORMATION
In the attachments there are:
- screenshot from DK showing photo Properties
- EXIF data exported with ExifTool
- one of the offending photos

Comment 1 andrej.valencic 2020-05-14 17:12:15 UTC

Created attachment 128458 [details]
DK screenshot

Comment 2 andrej.valencic 2020-05-14 17:13:49 UTC

Created attachment 128459 [details]
Offending photo

Comment 3 andrej.valencic 2020-05-14 17:14:10 UTC

Created attachment 128460 [details]
EXIF info

Comment 4 Maik Qualmann 2020-05-15 05:54:26 UTC

Of course, the problem cannot be reproduced here. Yes, we copy metadata to new images if they are recognized as already known in the DB. To e.g. not always having to scan all metadata again when copying images. We create the unique ID from the first 100KB and last 100KB of an image with an MD5 checksum. So it is quite unlikely that images will have the same unique ID. Therefore I cannot explain the problem at the moment. We should have the log from the terminal if you add an unknown image and this takes over the metadata.

Maik

Comment 5 andrej.valencic 2020-05-15 09:32:23 UTC

So I did another test and it looks like the problem is really only on this particular installation.

I copied and renamed some of these photos to my other laptop (Linux) with almost no photos on it. Then I run the latest appimage version of DK and the properties for the offending photos are empty as they should be.

So I'm wondering, what would happen if I copy those photos to another location not included in any of the DK collections (renamed them just in case). Then remove those photos from the DK (run Maintenance maybe), copy the "new" photos back to the Collection and refresh DK. Does it sound feasible to get different results?

Comment 6 andrej.valencic 2020-05-15 09:57:54 UTC

(In reply to andrej.valencic from comment #5)
> So I did another test and it looks like the problem is really only on this
> particular installation.
> 
> I copied and renamed some of these photos to my other laptop (Linux) with
> almost no photos on it. Then I run the latest appimage version of DK and the
> properties for the offending photos are empty as they should be.
> 
> So I'm wondering, what would happen if I copy those photos to another
> location not included in any of the DK collections (renamed them just in
> case). Then remove those photos from the DK (run Maintenance maybe), copy
> the "new" photos back to the Collection and refresh DK. Does it sound
> feasible to get different results?

Well this worked! I now have photos without wrong properties.