@GrecKo It does, but it seems to be a read-only reflection of the viewport set for the video frame objects that are coming through the videoSink. When I attempt to assign to it, I get the QML error: Invalid property assignment: "sourceRect" is a read-only property. The docs do not appear to reflect the fact that sourceRect is read-only. I am using Qt 6.3.

Looking at the source for VideoOutput (https://github.com/qt/qtmultimedia/blob/37c2d097eb5dd8671cc752dc920da11d66105905/src/multimediaquick/qquickvideooutput_p.h#L41), we can see that the Q_PROPERTY for sourceRect is read-only in both the 6.3 and dev branches.

I have had the thought of attempting to manually set the viewport of the QVideoFrameFormat of the frames coming through the VideoOutput's videoSink, but I haven't created a working solution for that strategy yet.

Thanks, I'll check that out. I might also look into the qtvlc option as well. It just makes me sad that I can't get a basic rstp stream to run with the built in mediaplayer.