rtmpdump -v -r "rtmp://212.243.210.71:1935/live?_fcs_vhost=cp49989.live.edgefcs.net/streamRM1@2564" -q | mplayer -

Se invece vuoi anche salvare lo streaming mentre lo guardi:

rtmpdump -v -r "rtmp://212.243.210.71:1935/live?_fcs_vhost=cp49989.live.edgefcs.net/streamRM1@2564" -o -| mplayer - -dumpstream -dumpfile Skytg24.mpeg