Jpeg support on Win7

vladstelmahovsky

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

SGaist

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.

vladstelmahovsky

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

SGaist

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

vladstelmahovsky

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

vladstelmahovsky

@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

vladstelmahovsky

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

SGaist

What is that Open Video editor ?

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