[MPlayer-dev-eng] Does MEncoder support pipe?

[The Wanderer]

I'm not quite awake enough to be sure I'm not somehow being an idiot
here, but:

Xie Bo wrote:

>> mencoder -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=800:mbd=2 -oac
>> pcm -ofps 24 svcdfile -o file.avi ffmpeg -i file.avi -acodec amr_nb
>> -vcodec copy -f 3gp file.3gp
>> 
>> anyway I couldn't find amr_nb. Additionally this is
>> mplayer-dev-eng, not mplayer-users
> 
> Sorry, I ask the question here is to ensure whether mencoder supports
> pipe out. (mencoder man page only shows a pipe sample). ("pipe out"
> means write to stdout, and "pipe in" means receive data from stdin).

At present that is not possible, because a lot of the text which can be
printed by MPlayer/MEncoder is output via stdout, and would corrupt the
output stream. If and when that gets corrected (I'm allegedly working on
it, others have done bits here and there), it will become possible to
implement output via stdout; when that's likely to happen, however, is
pretty much anyone's guess.

> And your above command is not pipe, neither pipe in nor pipe out. You
> use mencoder to write a file.avi instead of stdout and use ffmpeg
> read data from file.avi instead of stdin.
> 
> Why I want to use pipe? Because your above sample command need to
> write a big file.avi to hard disk and pipe doesn't need it!

Not if file.avi is a FIFO, i.e., a named pipe on the hard disk. That's
not exactly ideal conditions for encoding purposes, but it does avoid
storing large amounts of data on the hard drive; man mkfifo.

(And as Nico indicated, these are the sort of questions which belong on
mplayer-users, not on mplayer-dev-eng. -dev-eng is the developers' list,
meant for discussion of the programming of MPlayer, not the use of it.)

-- 
       The Wanderer, not dead yet!

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

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