vlc setting position and size of window has no effect (--video-x= --video-y= --width= --height= )

The following call has no effect of positioning and resizing of the vlc window:

cvlc -vvv --http-port=8084 rtp://239.255.12.43 --no-embedded-video --video-x=100 --video-y=100 --width=320 --height=200 --autoscale

It shortly shows the right window (black) but as soon the video from the camera is displayed, the window shows the video in its original size. The windows position is not at the given position (--video-y=100 --width=320) Thanks in advance for your help. Best regards Adolf