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Re: OpenMash Debian packages.
On Fri, 1 Feb 2002, Lawrence A. Rowe wrote:
> David Martinez CSIC RedIRIS wrote:
> There are good reasons for and against using rat as your audio tool.
> Lip synch is not one of them. Their lip synch cannot work on
> high-quality a/v streaming because of the overhead in using the mbus.
> Psychophysical modeling shows that people object to lip synch if the
> audio arrives 1/2 frame time early (i.e., 16.5 msec for NTSC) or 1 frame
> time late (33 msecs). I don't think you can meet those constraints
> using a message transmission between the two receiving processes.
> Moreover, you have to sample the clock drift on the audio chip crystal
> since most audio chips drift +/1 8 bytes every 64K samples.
Just to remark as a user of both MASH-vat and rat-4.2.X. As long as the
sound card is properly supported by rat, I have always noticed the quality
of sound (and only at testing 8K mono) to be more consistant, smooth and
comfortable using rat.
A simple example is here at home tonight, I ran vat to start and had hics
throughout the broadcast. Switch to rat and it smooths out and the sound
seems to be more inline with the picture more of the time. I use mrouted
over a cable modem through a long list of hops to work.
I don't know the internals anywhere near enough to comment as Lawrence
has, but just as someone who uses both, rat "appears" more developed.
Having said that, we mostly use vat on the desktops as they are all
windows and vat supports (for us) more sound cards.
Now, back to the iPAQ running Linux... rat will run (if in debug mode) but
vat complains of an unsupported sound card. Possibly because the iPAQ
sounds doesn't like 8k samples and wants 16k :(.
And not to leave everyone only slightly confused, UCL vic is blowing up on
the iPAQ, while MASH vic seems to startup much more dependably :).
Presently I am very thankfull for them both :),
JES
--
James B. MacLean macleajb@ednet.ns.ca
Department of Education http://www.ednet.ns.ca/~macleajb
Nova Scotia, Canada
B3M 4B2