The VideoLAN Forums

Our system is built as follows:

VLC windows (with webcam) ----) Darwin (Linux) ----) VLC client(Windows)

There's an incredible delay, about 10 seconds, and we don't know how to reduce it. We've tried many solutions like caching reductions and different codecs but no luck.

Here's an example command line that we use:

vlc.exe -vvv -I rc --ttl 50 dshow:// :dshow-vdev="Video Blaster WebCam 3/WebCam Plus (WDM)" :dshow-adev="none" :dshow-size="320*240" :dshow-amtuner-mode=1 :sout=#transcode{fps=10,vcodec=h264,vb=128}:duplicate{dst=display,dst=rtp{dst=ourserverip,port=1232,sdp=sap,sdp="file://C:\h264.sdp"}}

vlc.exe -vvv -I rc --ttl 100 dshow://:dshow-vdev="Video Blaster WebCam 3/WebCam Plus (WDM)" :dshow-adev="none" :dshow-size="" :dshow-amtuner-mode=1 :sout=#transcode{fps=10,venc="ffmpeg",vcodec=mp4v,vb=1024}:duplicate{dst=display,dst=rtp{dst=ourserverip,port=1232,sdp=sap,sdp="file://C:\prova2.sdp"}}

If we add encapsulation (mux=ts) VLC doesn't make the sdp file that is necessary for Darwin.

We think the problem is between Darwin and VLC client because if we use Quicktime as client player we have 5 seconds delay.

Any suggestion ?

Thanks

up

up

Hi,

Just had the same issue, in the streamingserver.xml (/etc/streaming/streamingserver.xml on my ubuntu system) file change the value of:

<PREF NAME="reflector_buffer_size_sec" TYPE="UInt32" >10</PREF>

To anything as low as zero,

I'm assuming that this protects against buffer underrun between the encoder and the darwin streaming server, in my case their in the same switch so I'm confident no/little buffer is needed but am guessing this default of 10 takes into consideration that the encoding/vlc machine may be on a WAN connection.

Hope this help (if you're still stuck)

Tristan.

I have the same problem, but i'm doing

Webcam, VLC -----------------> VLC server------------------> Windows media player.
UDP MMSH, ASF

And I have the same 10 sec delay.
I reduced it to 5 sec doing --sout-udp-caching 20 on the first VLC, --udp caching 20 and --sout-asf-packet-size 50 on the second.

But this 5 seconds are driving me mad because I have, in the first VLC server, if I display the movie there, 1 sec delay, but between the VLC and the WMP are the other 4 seconds.

Hi,



Just had the same issue, in the streamingserver.xml (/etc/streaming/streamingserver.xml on my ubuntu system) file change the value of:



<PREF NAME="reflector_buffer_size_sec" TYPE="UInt32" >10</PREF>



To anything as low as zero,



I'm assuming that this protects against buffer underrun between the encoder and the darwin streaming server, in my case their in the same switch so I'm confident no/little buffer is needed but am guessing this default of 10 takes into consideration that the encoding/vlc machine may be on a WAN connection.



Hope this help (if you're still stuck)



Tristan.

Yeahh! I'm just looking for answer on this forum and found it in your post!! Thank you Tristan!

Hi,
i m using a simple stream like VLC---------------------------VLC with the comand line:

vlc -vvv v4l:// :v4l-adev="/dev/audio" :v4l-vdev="/dev/video1" :v4l-norm=1 :v4l-width=320 :v4l-height=240 :v4l-fps=15 :v4l-audio=2 -- sout '#duplicate{dst="transcode{vcodec=mp4v,vb=1024,acodec=mpga,ab=192,sfilter=time,soverlay,channels=2,audio-sync}:std{access=udp,mux=
ts,dst=x.x.x.x}"}'

i use it ti transmit web cam image and voice. But de delay is always about 2 seconds. I try adding de option

--sout-udp-caching 10

but nothing change. How i can reduce this delay ?
thx a lot

Hi,
i m using a simple stream like VLC---------------------------VLC with the comand line:

vlc -vvv v4l:// :v4l-adev="/dev/audio" :v4l-vdev="/dev/video1" :v4l-norm=1 :v4l-width=320 :v4l-height=240 :v4l-fps=15 :v4l-audio=2 -- sout '#duplicate{dst="transcode{vcodec=mp4v,vb=1024,acodec=mpga,ab=192,sfilter=time,soverlay,channels=2,audio-sync}:std{access=udp,mux=
ts,dst=x.x.x.x}"}'

i use it ti transmit web cam image and voice. But de delay is always about 2 seconds. I try adding de option

--sout-udp-caching 10

but nothing change. How i can reduce this delay ?
thx a lot

you can try to see the rerun...
just kidding I think that your solution should work
I'll try to check it out further and c what will happen