[Live-devel] RTSP UDP multicast Streams and RTP video and audio on the same port

[Ross Finlayson]

At 03:44 PM 9/9/2005, you wrote:
>I have been using the 0.8.2 version of VLC for Windows.  I have been 
>trying to get this VLC client which uses your RTSP library to 
>properly communicate with our RTSP Server so that I can use RTSP to 
>start UDP multicast streams.  The VLC client will start the stream 
>OK but it can't play the video and eventually crashes.
>
>It seems that this only works using VOD unicast RTP streams.  I have 
>successfully run the VLC Server and Client on different machines and 
>gotten a VOD stream.  However changing the output from vod to 
>broadcast does not seem to work either.  Is this by design or am I 
>missing something?

As I don't know anything about your server, I can't help you much 
here.  But as I noted yesterday in response to someone else's 
question, it's up to the server to decide - based on the RTSP URL - 
whether the stream is multicast or unicast.

In any case, I suggest that you use the "openRTSP" command-line 
client - rather than VLC - to debug your server.  See 
<http://www.live.com/openRTSP/>.  If you give "openRTSP" the "-V" 
option, you will see the full RTSP protocol exchange.

>Also I am wanting to stream video and audio on the same port.  I 
>read in the FAQ that separating the streams is by design.  Does that 
>mean that the library only works with separate streams and that 
>combining them under RTSP is not possible?

No, once again this is something that's up to the server to 
decide.  However, most RTSP servers send separate RTP streams - on 
separate port numbers - for audio and video.  The main exception is 
servers that send MPEG Transport Streams (which contain audio and 
video multiplexed together in a single stream).


	Ross Finlayson
	Live Networks, Inc. (LIVE.COM)
	<http://www.live.com/>