On Fri, Jun 05, 2009 at 06:02:01PM -0400, Ryan Flannery wrote:
> With the recent work done to the audio system on OpenBSD, a buddy of
> mine and I figured it should be easy to setup two-way voice-chat
> between two OpenBSD clients using nothing more than aucat(1) and
> ssh(1). As we found out, it is both very easy and very usable! We
> have telephone-quality chatting working with a <= 1 second delay in
> the audio (after a few minutes of chatting, this is unnoticeable).
>
> First, a hearty thanks to Jacob Meuser and the other OpenBSD
> developers who have worked hard on this recently. Your efforts are
> both noticed and greatly appreciated.
>
> Second, I have a couple of questions...
>
> 1. We, the two users chatting (users neal and ryan) have ssh accounts
> on each other's machines. To voice-chat with each other, what we did
> boils down to the following:
>
> ryan# aucat -l
> ryan# aucat -o - | ssh r...@neals-machine aucat -i -
>
> User neal would do the same, only to my (ryan's) machine.
> When aucat is run in server-mode ('aucat -l') it creates a socket in
> "/tmp/aucat-USERID/default" where USERID is the uid of the user who
> ran the command (aucat -l). For another user (neal) to bind to this
> socket, we had to make this socket available to the other user, namely
>
> ryan# grep ryan /etc/passwd
> (find ryan's uid, call it RYANSID)
> ryan# grep neal /etc/passwd
> (find neal's uid, call it NEALSID)
> ryan# aucat -l
> ryan# cd /tmp/
> ryan# chmod 755 aucat-RYANSID
> ryan# ln -s aucat-RYANSID aucat-NEALSID
>
> Neal would do the same on his machine, only reversed.
> Question: is it possible to run aucat(1) in such a way that the socket
> it creates in 'global', such that other users can connect to it?
> A quick perusing of the man/archives and the source says no... but I
> may be missing something.
not yet. it's a bit of a can of worms ...
>
> 2. After doing the above, we would both simply do the following...
>
> ryan# aucat -b 1 -r 11000 -o - | ssh r...@neals-machine aucat -b 1 -r 11000
> -i -
>
> With the above -b and -r flags, the audio was not choppy at all, quite
> high-quality (equal to telephone quality), and overall very nice. We
> had about a ~1 second delay in the audio, however (neal's in Chicago,
> I'm in Cincinnati... we expected this), but could any of the
> developers familiar with the audio system see a way to perhaps
> decrease this delay? We played with other rates (-r values), but
> below 11000 the delay was about the same, and the audio became
> "deeper" and more "muted". Any other options, to aucat or perhaps
> audioctl, that one could play with to reduce this?
you could run the aucat server process with a smaller buffer. maybe
-b 1024. that's pretty low latency, maybe too much even. you could
try 8-bit encodings.
>
> Many thanks to the devs again... this rocks. and it's in base.
>
> -ryan
>
--
jake...@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org
