Created attachment 141108 [details] Example JP2 image SUMMARY Images that are reported as "JPEG-2000 JP2" (".jp2" file extension) do not open with Gwenview (nor is there a preview in Dolphin). GIMP is able to open JP2 files, though. STEPS TO REPRODUCE 1. Obtain a JP2 image (e. g. the attached one) 2. Try opening it with Gwenview OBSERVED RESULT Opening the image fails (type not supported). EXPECTED RESULT Gwenview should be able to display JP2 images. SOFTWARE/OS VERSIONS Operating System: KDE neon 5.22 KDE Plasma Version: 5.22.4 KDE Frameworks Version: 5.85.0 Qt Version: 5.15.3 Kernel Version: 5.11.0-27-generic (64-bit) Graphics Platform: Wayland Processors: 4 × Intel® Core™ i5-3570K CPU @ 3.40GHz Memory: 7.2 GiB of RAM Graphics Processor: Mesa DRI Intel® HD Graphics 4000 ADDITIONAL INFORMATION Apparently this issue already happened once back in 2009 and got fixed (Bug 183903). In the same year, a report had been filed for Krita (Bug 208578), which is marked as fixed. However, Krita currently is not able to open JP2 files either.
It works for me though on Arch Linux - Dolphin shows preview for the test file and Gwenview can open and display it fine. Do you have jasper and qt5-imageformats installed?
P.S. to my last comment: I have jasper, openjpeg2 and qt5-imageformats installed and it works for me.
qt5-imageformats and libopenjp2-7 are both installed jasper has nothing to do with JP2 images, it's a package for configuring ext2/3.
> It works for me though on Arch Linux If it works on Arch, then maybe we should move the issue to Neon User issues?
The Krita issue just got fixed (see https://invent.kde.org/graphics/krita/-/commit/542dcd306e236ec776a81e389d0a601387739e48) Maybe the cause is similar for Gwenview and Dolphin?
(In reply to Manuel Geißer from comment #3) > qt5-imageformats and libopenjp2-7 are both installed > jasper has nothing to do with JP2 images, it's a package for configuring > ext2/3. I am referring to https://github.com/jasper-software/jasper (https://www.ece.uvic.ca/~frodo/jasper/). On Arch Linux, qt5-imageformats depends on jasper.
It looks like many distros have dropped jasper, but in the end Arch Linux still keeps it because the upstream jasper repo eventually merged the security and maintenance fixes. [1] Meanwhile, from [2] I guess Qt may still rely on jasper for JP2 support. I think you can try checking whether your system has libqjp2.so, such as searching in `/usr/lib/x86_64-linux-gnu/qt5/plugins/imageformats/`. If it cannot be found then maybe qt5-imageformats is built without JP2 support. [1] https://bugs.archlinux.org/task/64655 [2] https://github.com/qt/qtimageformats/blob/dev/src/plugins/imageformats/jp2/qjp2handler.cpp
Thanks for these very helpful hints. Indeed, KDE Neon seem to have built qt5-image-formats-plugins without JP2 support. libqjp2.so is not present in the plugins directory. The image-related JasPer is not in Ubuntu/Neon, instead only [this jasper package](https://packages.ubuntu.com/focal/jasper), which had confused me first.
What exactly are the concerns about JasPer? As of 2021, it is actively maintained by the original author Michael Adams. There have been 8 releases this year, and the previous week's git history is full of commits. And JasPer seems to be fairly popular, too.
I believe it is now actively maintained so I also hope that other distros can include JasPer again. See also: https://github.com/jasper-software/jasper/issues/208#issuecomment-665471904
Removed in Debian in 2016 due to security fears https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=818209 I've now added an update of jasper into neon https://build.neon.kde.org/view/1%20release%20%E2%9B%B0/job/focal_release_forks_jasper/ and rebuild qimageformats https://build.neon.kde.org/view/3%20unstable%20%E2%98%A3%20git%20master/job/focal_unstable_qt_qtimageformats/ And gwenview seems to show the attached file Mind you this is the first time in 20 years I've ever come across anyone using jpeg2000 :)
Whoah, that was quick. Thank you!
I just installed the two packages. Works perfectly in Gwenview and Dolphin now :)