[Live-devel] Fwd: Why is RTSP needed apart from SDP?

[Juan Fernando Herrera J.]

Why can't one play unicast just from a SDP description? From a previous message:

> Ross Finlayson finlayson at live555.com
> Wed Oct 1 03:04:23 PDT 2008
> You can't (in general) play a unicast stream just by reading a
> SDP description, because the SDP description does not, by
> itself, contain enough information about the stream endpoints.

What's that missing information?

In detail: I want to transmit live captured unicast audio/video, and
I'm trying using testMP3Streamer and ffmpeg freely running,
independently (without establishing sessions because I know my clients
beforehand,) then clients would use VLC with a SDP file.

That's not working. I'm able to play the audio/video independently,
it's just concurrently that fails. Is an RTSP server necessary? My
understanding is that audio/video synchronization just comes from wall
time, why would an RTSP server be needed additionally?

Thanks,


Juan Herrera
Universidad EAFIT