[Error] Duplicate a stream

[Francoyy]

Hi, I'm trying to duplicate a stream into 2 outputs.

vlc -vvv C:\Movie.wmv --sout "#duplicate{dst=display,
dst=transcode{vcodec=h264,vb=500,scale=1,acodec=mp4a,ab=32,channels=2}:rtp{mux=ts,dst=127.0.0.1:1234,sdp=C:\vlc.sdp}}

That just doesn't work.. any idea why ? The "dst=display" is done, not the second dst..

main error: invalid chain
stream_out_transcode error: cannot create chain

[Francoyy]

up

[Francoyy]

apparently VLC can't make two simultaneous (and different) transcodings of an input stream, though it is said to be possible in VLC's doc

[Arite]

What do you want to do? Transcode to h264 and mp4a and then stream via rtp and display the output?

Try e.g.:

Code: Select all

vlc -vvv C:\Movie.wmv --sout "#transcode{vcodec=h264,vb=500,scale=1,acodec=mp4a,ab=32,channels=2} :duplicate{dst=display,dst=std{access=rtp,mux=ts,dst=127.0.0.1:1234,sdp=C:\vlc.sdp}}"

Arite.

[Francoyy]

Hi, thanks for your reply,

Actually I would like to transcode differently the two streams with one command : the goal is to save some webcam stream with a good quality in a file, and in a cheap quality in live streaming. So I would have to do something like this :
--sout "#duplicate{dst=transcode{etc}:standard{access=file,url="..."}, dst=transcode{etc2}:rtp{dst=servername,sdp=file:/...}}"

But no matter what, vlc can't seem to understand the dst=transcode

However it figures on the VLC tutorial http://www.videolan.org/doc/streaming-h ... /ch04.html

% vlc -vvv input_stream --sout '#duplicate{dst=
rtp{mux=ts,dst=239.255.1.2,sap,name="OriginalStream"},
dst="transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:
rtp{mux=ts,dst=239.255.1.3,sap,name="TranscodedStream"}"}'

[Arite]

Interesting - the Streaming Howto suggests that one can nest the transcode module within the duplicate module. The commandline I used was:

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vlc INPUT_FILE --sout "#duplicate{dst=display,dst="transcode{vcodec=mp4v,vb=1024,scale=0.5,acodec=mpga,ab=192,channels=2} :duplicate{dst=std{access=file,mux=ts,dst="OUTPUT_FILE"}}"}"

However VLC returns:

Code: Select all

main error: invalid chain stream_out_transcode error: cannot create chain

It could still be a syntax problem, or perhaps the current versions of VLC don't support the sout string described in the Streaming Howto.

Arite.

[Francoyy]

hmm so if the transcode module can't be nested in the duplicate module, I would have to duplicate the stream into two files/stream, and then open those two files/streams with vlc and transcode them the way I want ? that seems to a very dirty solution :s

[Stancho]

Hello all,

Francoyy, did you find a solution of this problem?
I would like to have 2 different streams from 1 webcam using vlc...

Thank you