[FFmpeg-user] add video delay

[tasos]

Hello.
I'm trying to create an output stream with delayed video.
I have already used
> ffmpeg -y -nostdin -loglevel error -report -i rtmp://foob  -itsoffset 
> 55 -i rtmp://foob \
> -strict experimental  -map 0:a -map 1:v -c:v copy -c:a copy \
> -f flv rtmp://foobar
>
> ffmpeg -y -nostdin -loglevel error -report -i rtmp://foo -strict 
> experimental \
> -delay 500 -c:v copy -c:a copy \
> -f flv rtmp://bar
but it doesn't seem to work.
Am i doing something wrong?
Thanks!