[SailfishDevel] How to access the viewfinder of the QCamera?

[Marcel]

Hi,

how can I access the viewfinder of the camera in Qt on SailfishOS?

If I try it in QML like this:

Camera {
  id: qmlCamera
}

VideoOutput {
  source: camera
  focus: visible
}

Or if I use C++ implementing an own QAbstractVideoSurface as viewfinder for a 
QCamera object (which would be my prefered way as I want to precess the image 
data) I get the following error:

[W] CameraBinSession::processBusMessage:912 - CameraBin error: "No common 
caps"

After some digging in the gstreamer debug log it seems that the camera source 
is just supporting the data format video/x-android-buffer and there is no 
equivalent QVideoFrame::PixelFormat for this. Is there really no possibility 
to access the viewfinder in Qt? Then how is the camera app doing that?

Greets,
Marcel