[FFmpeg-user] How do I decode once and pass frames to multiple destinations

[Simon Brown]

I have used ffmpeg for a number of different things, including decoding
streams, transcoding format, encoding streams, etc.  It's a wonderful
tool.  Now I want to design something that can do three things at the same
time, eg
a) display a stream on a monitor,
b) send the raw video out on a different medium and
c) scale and re-encode that video to restream out of the unit.

I can do all 3 of these things individually, and therefore I can do all 3
of these things by running 3 instances of ffmpeg, but at that point my
system is decoding the stream 3 times and I really don't want to spend the
CPU power doing that.

So is it possible to just decode the stream once, and then send it to HDMI,
scaler, etc. ?

Regards,
Simon