using VLC as RTP relay?

[prb]

Hi,
Is it possible to use VLC as rtp relay server? I would like to use VLC as pure RTP relay server without trans code option. Like the Darwin streaming server which has the Relay settings to receive rtp stream from remote machine and sending the stream over the network. Then any media player can receive the stream by specifying the rtsp url. Is it possible to achieve the same functionality using VLC? Please let me know.

Warm Regards,
prb

[Rémi Denis-Courmont]

Not really. VLC needs to demux the RTP stream and recognize the payload format, even though it does not need to decode/encode.

[lmallet]

Are you sure you can't do this?

I have been successfully setting up a RTP relay server using vlc 1.0.1. I deactivated transcoding and everything went fine.

However, I'm currently looking for a way to set up such relay server allowing a client to access the relayed stream using RTSP, as was possible with previous versions of vlc (e.g., 0.8.6i), but I don't know how to do it using the GUI. I suspect this is still possible using the command line but I don't know how and I'd prefer using the GUI.

Any hints? Or maybe you mean that this is what is impossible: accessing the relayed RTP stream via RTSP?

BTW, what will be the url of the sdp accessed by the client via RTSP?

Similarly, I don't really get the meaning of the "audio port" and "video port" settings in the RTP streamer configuration panel. How are they used?

Thanks.

[psanthu123]

Yes, RTSP is still possible with 1.0.1, Even i didnt find any GUI option for this, i am not sure whether this is missing, but you can edit the command(1. source, 2. Destination, 3. Option), In options tab, look for "Generated stream output string"

Here edit the options.
Eg: ":rtp{dst=192.168.0.100,port=1234,mux=ts}" change it to ":rtp{dst=192.168.0.100,port=1234,mux=ts,sdp=rtsp://192.168.0.100/test.sdp}" .

At client side, Open Network Stream, setect protocol as RTSP, address as 192.168.0.100/test.sdp
This works.

[isync]

Could you please post the whole command set, for the feeding vlc and the relaying vlc?
Thanks.

[psanthu123]

The above post was with GUI interface.

try using below command on command line
vlc -vvv sample_file :sout=#transcode{vcodec=h264,vb=800,scale=1,acodec=mp4a,ab=128,channels=2,samplerate=44100}:rtp{dst=192.168.0.100,port=1234,mux=ts,sdp=rtsp://192.168.0.100/test.sdp}

or without transcoding
vlc -vvv sample_file :sout=#rtp{dst=192.168.0.100,port=1234,mux=ts,sdp=rtsp://192.168.0.100/test.sdp}

Check out http://wiki.videolan.org/Documentation: ... e_Examples if you are using 0.9 version

[weeraman]

Hi,
IS there a possibility of transcoding a RTP stream (with higher bit rate) to a lower RTP stream and get the SDP file?
Basically I want to use a same high quality encoded stream to make a new RTP stream.
Following is the current setup >>

Encoder 1 - 10.48.233.10
------------------------------
destination- 224.0.0.1
audio codec -AMR NB
audio br -10.2k
audio port -5002
video codec - H.263
video br -90k
video port -5000

I want to use the same stream to make a new stream with different streaming parameters. (only change in video/audio bit rates/ ports)

so finally i've two streams of same content with different qualities.
I couldn't find an exact way to do this.
if someone know please let me know i'll try


Thanks In advance
Nilanka.

[Rémi Denis-Courmont]

You can transcode RTP to RTP, yes.

[peppe333]

Hi all, I've a similar problem.
I have a 48kbps local unicast stream (RTSP protocol) and I've successfully tried to relay it in multicast streaming (RTP protocol) without transcoding with the following command
"rtsp://@192.168.123.249/stream.sdp" ":sout=#duplicate{dst=rtp{dst=230.230.230.230,port=6000,mux=ts},dst=display}"

but the problem is that the final VLC's output stream (in RTP) is more than 80kbps (measured by DuMeter) instead of about 48kbps, why?
I've checked the multicast clients and they receive 80kbps of input (measured by DuMeter), even if on the VLC player statistics the stream is indicated in 48kbps.
What are the exceeding data that VLC send to clients? Can I prevent VLC from sending them?
It's a great problem for me, because my upload band is only 64kbps and I have to reduce the encoding quality to 24kbps (which is relayed by VLC in RTP at about 50-55kbps) to stay within my 64kbps upload limit.
Can anyone help me?
Thanks.

[Rémi Denis-Courmont]

You are muxing to MPEG-TS. That adds overheads.

[peppe333]

You are muxing to MPEG-TS. That adds overheads.

Thanks for your quick reply and your help.
I've tried to delete the mux command, and now correctly the server send a 30kbps stream and the clients receive a 30kbps stream (for a 24kbps stream), but no sound can be heard on the client side even if the data are received, it's like VLC clients weren't able to read and play the relayed stream without muxing.
May it depend on the fact the the initial unicast stream is encoded in AACplus by Opticodec-PC SE?
It's very strange, because VLC before the relay is able to read the Unicast Stream by Opticodec, but the same stream after the multicast relay is no more readable by the clients (which use VLC too), and the stream can be read only if muxed with TS.
I've found this document on Orban Opticodec http://www.orban.com/plugin/Read_Me.html
in which are indicated the supported live stream types (and MULTICAST RTP in still UNDER DEVELOPMENT). Maybe is this the problem?
If this is problem, please, can you tell me if exists another encoder (better if in AACplus, otherwise also in OggVorbis or in AAC are good), which can be connected directly to VLC like Opticodec?

[Rémi Denis-Courmont]

That depends how you open the stream. If you don't mux you MUST use a SDP with all elementary streams.

[peppe333]

That depends how you open the stream. If you don't mux you MUST use a SDP with all elementary streams.

How can I do it? How should I change this string on the server?:
"rtsp://@192.168.123.249/stream.sdp" ":sout=#duplicate{dst=rtp{dst=230.230.230.230,port=6000},dst=display}" (this is my actual string with mux deteled)
Sorry, I'm a newbie.
Thanks in advance for the help.

[Shlomo]

I am not sure that his is what I am looking for.
I want to use VLC to relay an RTSP stream that I receive from a local WiFi camera, via the Android network (3G) to a remote Wowza server on the internet.
Can it be done? how?