[FFmpeg-devel] [RFC] SDP Generation
Mon Jun 11 09:06:54 CEST 2007
Michael Niedermayer wrote:
>> Well, the problem is that every single media stream can have a different
>> destination address. If the "filename" field in AVFormatContext is used
>> for indicating the destination address, then I need an AVFormatContext
>> per media stream.
> in what cases are different destination addresses needed/wanted?
The classical example is video streamed to a multicast group, and audio
streamed to a different multicast group. If an application wants to
receive both audio and video, it joins both the two groups; if an
application wants to receive audio only, it only joins the audio group.
In this way, if multicast is routed in a smart way it is possible to
reduce the network traffic.
> and why do we need them in a single SDP thingy?
Because both audio and video streams are part of the same session.
> i can also put each stream into a different file, this though does not
> prevent me from putting them in the same file ...
Do you mean, each stream described in a different SDP file? In this
case, how can a receiving application understand that the streams are
part of the same session? Or did I misunderstand you here?
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