ffmpeg -i
http://archive.org/download/BunkerHi...kerllBunny.mp4 -pix_fmt gray -vf transpose=2 -vcodec rawvideo -f rawvideo -r 7.8 -y -s 600x800 - |./raw2gmv | nc -l 5555
was the magic formula for me.
Thanks for all the pointers, don't know why it failed before.