[MEncoder-users] Can you slow down mencoder?

[D Richard Felker III]

On Thu, Mar 10, 2005 at 03:24:36PM +0000, Jonathan Lundberg wrote:
> Hello all,
> 
> My situation is that I need to encode the same content from a video grab 
> card to two different
> bitrates at the same time.  The files need to be ready for use at 
> roughly the same time (ie, the end
> of the show!).  Unlike Windows Media Encoder, or Helix Producer, it's 
> not possible with mencoder
> to grab to two different output rates at the same time (or am I wrong???).
> 
> What I have to do is grab from the tv capture card to filename.avi, and 
> while it's still grabbing from the
> tv card, run mencoder against filename.avi to also produce an identical 
> file at a lower bitrate.  My
> problem is that the second mencoder runs faster than real time, catches 
> up with the end of the file,
> and then exits while the primary encode is still running. 
> 
> Is it possible to slow down mencoder so that it also runs in realtime, 
> so that if I
> start it running 10 seconds after the initial grab, it'll run second by 
> second against the file being grabbed,
> instead of 'as fast as computerly possible'?
> 
> Or is there some other way to feed the content of filename.avi into 
> mencoder in real time for encoding?

Look up fifos (mkfifo) and the "tee" program. These should be able to
help you do the trick.

Rich