[opus] repacketizing unrelated frames

Benjamin Schwartz ben at bemasc.net
Fri Jul 26 22:55:44 PDT 2013


The multistream API lets you specify things like "take these 8 input
streams and encode them as 4 stereo pairs in the following arrangement",
and produces output that includes all 4 stereo encodings glued together
into one packet.  That packet can then be losslessly split at some later
point.

If you need to mux some freshly-encoded streams and some streams that were
previously encoded ... well, you might have to write some code yourself,
but you can still use the same bitstream format as Multistream.


On Fri, Jul 26, 2013 at 6:55 PM, Marc Lindahl <marc at bowery.com> wrote:

> Hi Jean-Marc,
>
> I looked at that but importantly these streams need to remain absolutely
> independent,
>
> Further they may have been encoded at some previous time.
>
> So my question stands.
>
> Thanks,
> Marc
>
>
> On Jul 26, 2013, at 9:10 PMEDT, Jean-Marc Valin wrote:
>
> > Hi Marc,
> >
> > I recommend you have a look at the multistream API and how we use it for
> > surround in the Ogg Opus draft. Sounds like the best way to solve your
> > problem.
> >
> > Cheers,
> >
> >       Jean-Marc
> >
> > On 07/26/2013 06:57 PM, Marc Lindahl wrote:
> >> I can't quite figure this out from looking at the repacketizer code.
> >>
> >> Let's say I have 4 separate stereo streams (say from an 8 channel
> >> converter)  and want to transmit them somewhere in one stream e.g.
> >> RTP or the like.  (assuming, custom format if necessary)
> >>
> >> So could I merge 4 packets with the repacketizer, TX the merged
> >> packets, on the other side RX them then split them with the
> >> repacketizer, and feed each of the 4 to a separate decoder to recover
> >> the audio?
> >>
> >> Or when you merge do the 'states' get blended somehow on the
> >> assumption the audio is all the stream, monotonically increasing
> >> time-wise?
> >>
> >> Thanks!
> >>
> >> Marc _______________________________________________ opus mailing
> >> list opus at xiph.org http://lists.xiph.org/mailman/listinfo/opus
> >>
> >
>
> _______________________________________________
> opus mailing list
> opus at xiph.org
> http://lists.xiph.org/mailman/listinfo/opus
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.xiph.org/pipermail/opus/attachments/20130726/acb282f0/attachment.htm 


More information about the opus mailing list