SUMMARY On some JPG images, face tags are not saved into the file. This happens EVEN if I've set digikam to use Exiftool to write metadata to file, e.g. as per this thread: https://bugs.kde.org/show_bug.cgi?id=448729 Because of the error (as below) it seems none of the metadata changes are saved into the file, but I only tag faces (and want them to be written to the file) DebugView shows this error: digikam.metaengine: Cannot export changes with Exiv2 backend: (Error # 38 : "Size of XMP JPEG segment is larger than 65535 bytes" STEPS TO REPRODUCE 1. Open a 'problematic JPG' in digikam 2. Apply a facetag 3. Observe (in another tool) that the facetag has not been written to the file 3. Observe (in DebugView) that digikam threw this error: digikam.metaengine: Cannot export changes with Exiv2 backend: (Error # 38 : "Size of XMP JPEG segment is larger than 65535 bytes" digikam.metaengine: Exiv2 error exception for "<filename>.jpg" Writing of metadata aborted! OBSERVED RESULT Face tag has not been written to the JPG file EXPECTED RESULT Face tag is written into the JPG file SOFTWARE/OS VERSIONS Windows: Windows 11 Version 25H2 (x86_64) Qt Version: 6 ADDITIONAL INFORMATION
PS: I noticed 'by accident' that writing the face tags into some files... Perhaps a warning should be shown is metadata is not saved into the file? (I make a point of storing [whereever possible] metadata into the file, as to not get 'stuck' into a particular tool. So it's important to me that my efforts to e.g. set GPS coordinates, or tag faces, really are written into the file...)
The ExifTool Backend is only used to read and write metadata to files. Internally, digiKam continue to encode and decode metadata with Exiv2 containers so this kind of error still possible. Note: ExifTool support the Exiv2 containers to stream metadata. Gilles Caulier
(In reply to caulier.gilles from comment #2) > The ExifTool Backend is only used to read and write metadata to files. > Internally, digiKam continue to encode and decode metadata with Exiv2 > containers so this kind of error still possible. > > Note: ExifTool support the Exiv2 containers to stream metadata. > > Gilles Caulier Thanks for you quick response! So... for images where 'XMP JPEG segment is larger than 65535 bytes' metadata can simply not be written to the file? (Note: I really LOVE digikam and am VERY grateful all the efforts all contributors are putting in!! Just trying to get 'clarity; :-))
yes exactly. The bug is located in Exiv2, and already reported since a while and not yet fixed: https://github.com/Exiv2/exiv2/issues/1549
*** This bug has been marked as a duplicate of bug 468830 ***