How to get the supported resolution of a QCamera

Andy314

QList<QSize> res = Cam->supportedViewfinderResolutions();
gives alwas a 0-Length list.
(Qt 5.6.0 MSVC-2015 - 32 bit)

Joel Bodenmann

Hi,
I've never used QCamera myself but as nobody replied yet I'll give it a shot...
The documentation states:

The camera must be loaded before calling this function, otherwise the returned list is empty.

So, did you load the camera before calling QCamera::supportedViewfinderResolutions() ?

? Offline

@Andy314 Hi! What @Joel-Bodenmann said is correct; you must wait until the camera status has changed to loaded. You can use QCamera::statusChanged signal for this:

QList<QCameraInfo> cameras = QCameraInfo::availableCameras();
m_camera = new QCamera(cameras.at(0), this);
connect(m_camera, &QCamera::statusChanged, this, &MainWindow::onStatusChanged);
m_camera->load();

// ...

void MainWindow::onStatusChanged()
{
    qDebug() << m_camera->status();
    qDebug() << m_camera->supportedViewfinderResolutions();
}

Andy314

Sorry I pasted the the wrong test-code.
(The supportedViewfinderResolutions() works indeed, but I need the natural camera-resolution.)

Capture = new QCameraImageCapture(Cam);
QList<QSize> res = Capture->supportedResolutions();

List ist empty after loaded signal!!!

My aim it to retriever the possible resolutions of a camera, choose a possible resolution and make a capture with this resolution.

If found the code above in the integrated Camera example of the Qt.
The direct compiled example does not work as well.

Andy314

I found this link:
Multimedia Backends
I seem that in Qt 5.5 (dont know what is with 5.6) for Windows the Camera in not really supported. :-(((
Any ideas how to integrate camera functionality in a Qt-App ?