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Hi everyone,

I would like to change some parameters of a video while it's playing such as bitrate, width ...

I try this a the telnet control : So, first question: Is there a simpler mean to do this ?

But now I have to implement a software (on the streaming server) which can adapt the width, etc of a video when the client send a message to the streaming server. I tried to do the same thing like I have done with the telnet interface but functions I use may not be in the API : It seems normal because : Here is my sample code : Any ideas ?

Thanks.

PS: I'm using libvlc0-dev

cat /usr/include/vlc/*.h | grep libvlc_vlm

This is because you must work with latest version of vlc (yet unstable) to access all of API's functions referenced here http://www.videolan.org/developers/vlc/ ... ibvlc.html

latest vlc is here http://nightlies.videolan.org/

Ok thank you I'll test this afternoon

Edit: It seems to work but I still have some troubles : Are all modules implemented on vlc 0.86 available on this version ?
Even with the Qt interface I tried : Media -> Streaming -> Stream -> RTP (:sout=#duplicate{dst=rtp{,dst=192.168.1.2:1234}}) -> Stream but I didn't success in streaming my video (I get an other window with some error messages).

What can I do ?

works for me :
./vlc -vvvv rtsp://192.xxxx --sout '#transcode{vcodec=h264,vb=1024,scale=1}:rtp{mux=ts,dst=192.xxxx}'

[00000336] main stream output debug: stream=`rtp'
[00000340] main stream out debug: looking for sout stream module: 1 candidate
[00000340] main stream out debug: set config option: sout-rtp-mux to ts
[00000340] main stream out debug: set config option: sout-rtp-dst to 192.xxxx
[00000343] main mux debug: looking for sout mux module: 1 candidate
[00000343] mux_ts mux debug: shaping=200000 pcr=70000 dts_delay=400000
[00000343] main mux debug: using sout mux module "mux_ts"
[00000343] main mux debug: TIMER module_Need() : 2.487 ms - Total 2.487 ms / 1 intvls (Avg 2.487 ms)
[00000336] main stream output debug: muxer support adding stream at any time
[00000336] main stream output debug: muxer prefers to wait for all ES before starting to mux
[00000340] stream_out_rtp stream out debug: maximum RTP packet size: 1400 bytes

Maybe your command line is wrong (but you didn't post it so I just tried to guess what you want to do)
Or you don't have rtp module ?

try this :

./vlc --list | grep rtp
VLC media player 0.9.0-test3 Grishenko
stream_out_rtp RTP stream output
rtp (Experimental) Real-Time Protocol demuxer

I've the RTP module I think : In fact what I want to do is this :
- the server (the application I had to develop) is listening
- the client send it a sip message with its features (such as its resolution)
- the server starts the streaming of the video (in RTP) with the destination the IP address of the client
- during the video is playing the client realize that the there is a lot of traffic and the fluidity is decreasing. So it send an other SIP message containing the command "decrease the bitrate" (for instance).

So the server must be able to adapt these parameters on the video. And, I chose VLC because it is for me the project the most successfully completed.

I am writting my application in C and I use libvlc.
My commande line was (the one I used in vlc 0.86) : but I try to do the same as the command line in C to have a control on the instance from my apllication (for instance decrease the bitrate).

Your second command line is wrong so you need to look out vlc documentation and rewrite it with something like :
'#transcode{vcodec=h264,vb=1024,scale=1}:duplicate{dst=rtp{mux=ts,dst=192.168.1.33:1234}}'
which seems to works.

You should read
http://www.videolan.org/doc/streaming-h ... /ch03.html
" rtp: streams over RTP This can only be used to stream MPEG-TS over plain RTP. Support for this option has been removed in VLC 0.9.0 and latter. You should use the rtp stream output module instead. Options are the same as for the udp setting. "

Hi,

OK. Works fine now with this sample command :

vlc /home/partage/Videos/pepsi_baeren.mpg --sout "#transcode{vcodec=mp4v,vb=1024,scale=2}:duplicate{dst=rtp{mux=ts,dst=192.168.1.34,port=1234}}"

However I didn't success in transcoding the stream in h264 (the current version 0.86 of VLC support) this.with :

vlc /home/partage/Videos/pepsi_baeren.mpg --sout "#transcode{vcodec=h264,vb=1024,scale=2}:duplicate{dst=rtp{mux=ts,dst=192.168.1.34,port=1234}}"

[00000001] main libvlc debug: translation test: code is "C"
[00000001] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
[00000493] avcodec encoder error: cannot find encoder H264 - MPEG-4 AVC (part 10)
[00000403] stream_out_transcode stream out error: cannot find video encoder (module:any fourcc:x264)
[00000403] stream_out_transcode stream out error: cannot create video chain
[00000491] main packetizer error: cannot create packetizer output (mpgv)

Thanks again.

Edit:

With a good string my application works but when I call : I got this message in my console :

show : (null)
l libvlc_vlm_show_media: Resource temporarily unavailable

sorry I don't know about that, and this is another issue you should post in another forum section.

OK I will post it in an other section.

Thanks a lot.

are you aware your configuration has both '--disable-x264' and '--enable-x264' .. last one is disable this might be causing the x264 encoder module to be not loaded.

hello darkweaver,
i don't know if it is the right way to ask,but i wanted to ask as how far you could get the project woking.we're doing a similar project for the college purpose,and wanted all the help i can.
please do let me know about how i can contact you otherwise,by mail.all help will be appreciated.

regards.
vinu.
[vinu.viking@gmail.com]

Hi,

I don't think I can help you because my team and me, because of the bug I posted for, have given up vlc to do what we wanted. After that, we chose to use GStreamer which is more complex but works for our subject.

I can't help you anymore on vlc.

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