[PLUG-AV] Quick update

[Tim Bowden]

On Tue, 2011-05-17 at 20:50 +0800, James Bromberger wrote:
> On 17/05/2011 8:24 PM, Tim Bowden wrote: 
> > On Tue, 2011-05-17 at 19:50 +0800, James Bromberger wrote:
> > > I suspect USB3 may be a requirement; I see PCI-E cards for $22 and
> > > $17 on deal extreme. But that does then rule out laptops and rule
> > > in SFF desktops (most nettops don't have PCI/PCI-E). 
> > If it can be passed through a USB3 port on the shuttle fast enough (ie,
> > as fast as the shuttle HDMI input gets the stream), then there is no
> > need for a camera PC at all.  
> The main thing that I am yet to see is the performance of USB3. And I
> don't mean the quoted bandwidth, but the load placed upon the CPU. The
> main reason why firewire wins over USB2 is not speed; its the load
> that USB puts on the CPU (by way of interrupts) that firewire doesn't.
> Firewire has rock solid timing, so no data is ever delayed or
> buffered; USB is subject to CPU scheduling.
> 
> > The shuttle device would replace that.
> > The only PC in the whole setup would be the mixing box.  Downside is
> > we're limited on the maximum distance of cameras from the mixing box "as
> > the cable runs" to 25m.  Probably a bit short as the max distance from
> > the mixing box, but then why can't the mixer sit at a second low powered
> > box (even in another room/annex?) and remote login to the full powered
> > headless mixing box that could sit anywhere suitable for the cameras?
> > That way the maximum distance between any two cameras could be up to 50m
> > (theoretically).
> So I tried using dvswitch over VNC; that's a no go- the main video
> window, which issue Xv to some such to render, is not shown over a VNC
> link.
> 

Ouch.  That idea won't work then.

> I would still like to have each cam op on a headset, and that requires
> the local PC to be working. We dint try mumble last week as we were in
> a very small space so it didn't make sense. We should try this
> somewhere bigger - more spread out. So I dont think we get rid of the
> camera capture boxes; the ones we have now, although large and in need
> of quieter fans, are doing the job.
> 

I forgot about the mumble bit.  OK, so we do need a pc with gbe, pci-e
and audio in/out.

> I just re-watched our video, and the flickering of the P-in-P happens
> from both cameras. I suspect it was the box we were using being
> underpowered. But we have a much more powerful box in AV 2 now up and
> running. Jason: what's the size of the fan thats really noisy in AV2
> there with you?
> 
> Having another machine outside that's doing stuff - well, definitely
> an option for the OGG encoding; that's what we did at UCC. But if we
> get a quad core CPU into the AMD mobo AV2 box, then we may be sorted??
> 
>   James

Tim