[BXXPwg] multiple ANS interleaving...

Joe Touch touch@ISI.EDU
Thu, 21 Dec 2000 17:23:10 -0800


Darren New wrote:
> 
> Joe Touch wrote:
> > The suggestion was that multiple ANSs could be
> > interleaved (from different MSGs), thus interleaving
> > audio and video components and synchronizing the
> > playout of a file.
> 
> Actually, my comment was that different frames of different ANSs in answer
> to the same MSG could be interleaved. However, that wasn't really the thrust
> of the discussion.
> 
> > That being the case, there appears to be no way
> > to synchronize playout using ANS. One could use
> > MSG/RPY pairs alternating audio and video on
> > a single channel, though, but not multiple ANSs.
> 
> Frame 1 of ANS 1 to MSG 1  <- first audio chunk
> Frame 1 of ANS 2 to MSG 1  <- first video chunk
> Frame 2 of ANS 1 to MSG 1  <- second audio chunk
> Frame 2 of ANS 2 to MSG 1  <- second video chunk
> Frame 3 of ANS 1 to MSG 1  <- third audio chunk
> Frame 4 of ANS 2 to MSG 1  <- third video chunk
> 
> You can interleave *frames* from different ANSs in response to a single MSG.

Frame interleaving depends on the muxing underneath (the mapping).
Since the protocol (beep-framework) doesn't specify a mapping, 
you can't assume a particular property of the mapping.

I'm still confused by the above in either case, though.
It interleaves ANS1 and ANS2 frames - it seems like
the ANS must come in order, just as the MSGs did.

Joe