Opened 12 years ago

#794 new defect

Allow all messages to stderr / Messages channel inconsistency

Reported by: bjung50169@… Owned by: reimar
Priority: normal Component: core
Version: unspecified Severity: minor
Keywords: Cc:
Blocked By: Blocking:
Reproduced by developer: Analyzed by developer:


How about having an option to force mencoder to output all its messages to stderr, so that one can have messages on the console *while* data is piped to another program? Or better, to be more consistent, force all messages to stderr by default, like i.e. "swscaler" does anyway?

It could save others the hassle figuring out and solving the problem that the initial messages (version and cpu info), as well as some other messages, silently pollute output pipe data. I see that mencoder doesn't output those when redirecting stdout to a file, but some other messages are still allowed through, which is inconsistent with the pipe behaviour, but equally useless, and is IMO a confusing hack. At the very least you'd expect that "mencoder > outfile" would behave the same as "mencoder | cat > outfile" !!! Try the following two lines and examine the files:

mencoder /dev/zero -demuxer rawvideo -rawvideo w=2:h=2 -o - -ovc raw \

| cat > out

mencoder /dev/zero -demuxer rawvideo -rawvideo w=2:h=2 -o - -ovc raw \


As for the workaround, having to demand complete silence from mencoder when piping output does not only denies scripts users useful feedback, but may also mask potentially important warnings or errors, for users and developers alike.

I'm actually surprised such a "feature" was not already reported before, meaning that nobody else mixes mencoder with external compressors (like theora) and/or that everybody else uses huge intermediate video files!

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