Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

TIFF file problems in qt6



  • Hi there!

    In qt5+, I had no problems opening (non-tiled) regular TIFF files. We have a software that opens all png, jpg and tiff files in a directory - and that works just fine on qt5.

    When upgrading to qt6, tiff files that are loaded (img.load("blah.tiff")) will have a reported size of (0,0). No warnings or errors are issued. Using qt6.0.0 desktop (windows MSVC 2019, macOS clang) provided from the maintenance tool downloader.

    Any ideas?


  • Lifetime Qt Champion

    Can you provide a small tiff file to reproduce the issue? Maybe open a bug report and assign it to me.



  • @leuat Hi, there is optional plugin imageformats (available for download via the Maintenance Tool) - it is provided as source code only and you need to build it in order to use it. Have you done that?

    EDIT: re TIFF support





  • @artwaw ah, thanks - that was .. unexpected. I'll see if I can make it work on a windows pc when I'm back at work, I'm currently on Apple M1 and have built qt 6.0.0 from scratch for ARM (same issue is here as well). Some questions then:

    a) Will the image formats plugin be available pre-compiled as a plugin download in the future? My software package(s) is (are) deployed to windows/linux/macOS (x86 + arm), which means there will be a hell of a lot of stuff to maintain / compile up. Right now, I'm having enough trouble with ARM stuff + getting Qt6 to work as it is

    b) It would be nice if trying to use a non-installed plugin in qt6 would yield an error / warning instead of simply.. doing nothing. This error fell completely through our testing, as we weren't aware of the problem until several users started reporting garbage 128-byte empty tiff files everywhere.

    Anyway for now we're considering rolling back to qt5 unless I get the image plugin working. Thanks for the reply!

    (and to compensate for the negative vibe : qt is awesome. I wouldn't have been able to do all this stuff without your amazing framework!)


  • Lifetime Qt Champion

    They will be provided once they're ported to CMake.
    Currently there is no reason to use Qt6.0 at all due to such incomplete stuff.



  • FYI the problem was resolved after manually compiling up the imageformats package + adding it to the build dir. For future references: please make sure that if you try to load an image file that is currently not supported, then provide some sort of feedback to the user (developer)!


Log in to reply