https://github.com/qt/qtmultimedia/blob/5.12/src/plugins/avfoundation/mediaplayer/avfvideoframerenderer.mm#L123

Took me a while to figure out how to use it though as it didn't work for me and was crashing the app right on start when the code was part of a plugin (QObject). Unfortunately I was not able to Google it properly (didn't bump into anything that would say that usage is incorect), however with some luck and a lot of trial and error I found out it works when one creates this in the main.cpp file and then simply replies on the QOpenGLContext::currentContext().

And then considering QVideoFrame::map works on UT as part of the Camera QML object I would presume both methods need to work somehow :(. I am just obviously not doing something properly as it is failing for me as described above ^.

https://github.com/qt/qtmultimedia/blob/5.12/src/multimedia/video/qvideoframe.cpp#L1094

OpenGL context is not current, cannot map memory.

And when I try to use the QOpenGLContext::currentContext() is doesn't work either. What is more QOpenGLContext::functions() is killing my app (looks like bad memory access?) and that has probably something to do with the fact the context is not defined? I wish I knew more :(, but I also tried creating that context and it didn't have any impact.

This is the minimalistic example just added to the Clickable C++ template that crashes for me:

#include <QGuiApplication>
#include <QQmlApplicationEngine>

#include <QOpenGLContext>
#include <QOpenGLFunctions>

int main(int argc, char* argv[])
{
    QGuiApplication app(argc, argv);
    QQmlApplicationEngine engine(QUrl("qrc:///Main.qml"));

    QOpenGLContext *ctx = QOpenGLContext::currentContext();
    QOpenGLFunctions *f = ctx->functions();

    return app.exec();
}

Any ideas what could be causing that? My attempts were so far quite futile too
Thanks a mil!

EDIT:
I later found out where the QVideoFrame::map error is coming from:
https://gitlab.com/ubports/development/core/qtubuntu-camera/-/blob/main/src/aalvideorenderercontrol.cpp

As well as how to initialize the OpenGLContext - see per post bellow.

This approach is what I wanted to avoid, but probably, it would be the most feasible solution right now, and I might go that route. Thanks for the hint!

Yes. There are some devices which have issues using the VideoFilter method, so I had to do the manual sampling that way instead.

Looking at the issue you opened, it might be the same problem as I ran into which forced me to using the manual sampling. The issue is actually in the qtubuntu-camera QPA which we provide so that QtCamera API can use the camera hardware via Android HAL.

Gonna check out authenticator-ng

[edit] as per https://gitlab.com/dobey/authenticator-ng/-/blob/trunk/src/qml/ScanPage.qml this app does not use a videofilter. Instead, images are taken every 250ms and then passed to qzxing.

This approach is what I wanted to avoid, but probably, it would be the most feasible solution right now, and I might go that route. Thanks for the hint!

First of all, thanks for the radio app. I'm currently testing/using it and it's great to be able to have access to my favorite radio on my phone.

IIRC, Dobey uses qzxing for authenticator-ng.
I'll take a look at his git and borrow some code.
https://gitlab.com/dobey/authenticator-ng

I think what you're struggling with is pakaging the lib within your click package.