Jpeg support on Win7



  • Hi

    I have a problems loading jpeg files under Windows 7 with official Qt 5.7.0 MSVC2013 32 bit and my own built 5.8.0 (dev branch) MSVC2013 32 bit
    I have a mssage something like:
    QML Image: Error decoding: blabla.jpg: Unsupported image format
    jpeg(d).dll plugin is on the place

    what else I can check?

    thanks


  • Lifetime Qt Champion

    Hi,

    Start your application with the QT_DEBUG_PLUGINS environment variable set to 1. You'll see what happens with the plugin at startup.

    You can do that in the Run part of the Project panel of Qt Creator.



  • Thanks!

    Found this:
    QFactoryLoader::QFactoryLoader() looking at "C:/development/qt5/qtbase/plugins/imageformats/qjpeg.dll"
    Found metadata in lib C:/development/qt5/qtbase/plugins/imageformats/qjpeg.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "jpg",
    "jpeg"
    ],
    "MimeTypes": [
    "image/jpeg",
    "image/jpeg"
    ]
    },
    "className": "QJpegPlugin",
    "debug": false,
    "version": 329728
    }

    "The plugin 'C:/development/qt5/qtbase/plugins/imageformats/qjpeg.dll' uses incompatible Qt library. (Cannot mix debug and release libraries.)"
    not a plugin

    and how to fix this?

    thanks


  • Lifetime Qt Champion

    Build Qt for both debug and release, or build your application in release mode.



  • @SGaist Actually, Qt was built in both modes, using -developer-build -debug-and-release flags



  • @SGaist oops, there is more with jpegd.dll:

    QFactoryLoader::QFactoryLoader() looking at "C:/development/qt5/qtbase/plugins/imageformats/qjpegd.dll"
    Found metadata in lib C:/development/qt5/qtbase/plugins/imageformats/qjpegd.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "jpg",
    "jpeg"
    ],
    "MimeTypes": [
    "image/jpeg",
    "image/jpeg"
    ]
    },
    "className": "QJpegPlugin",
    "debug": true,
    "version": 329728
    }

    Got keys from plugin meta data ("jpg", "jpeg")

    it seems, plugin is registered



  • Well, problem solved...by uninstalling Open Video editor
    The problem, obviously in Qt's plugin loader subsystem, where non relevant plugins marked as non relevant still tried to load but failed


  • Lifetime Qt Champion

    What is that Open Video editor ?

    What do you mean by "non relevant marked plugins" ?


Log in to reply
 

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.