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Re: video capture H/W??

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In article <gjxI70UYBlcC-pn2-BGnmrzLvDdYF@trevor2.dsl.pipex.com>,
Trevor Hemsley <Trevor.Hemsley@mytrousers.ntlworld.com> wrote:
> On Mon, 30 May 2011 19:23:28 UTC in comp.os.linux.hardware, 
> ebenZEROONE@verizon.net (Hactar) wrote:
> 
> > In article <irr11h$ld9$1@dont-email.me>, J G Miller  <miller@yoyo.ORG> wrote:
> > > On Friday, May 27th, 2011 at 19:21:01h -0400, Bill Marcum explained:
> > > 
> > > > With a USB camera, you don't need any additional hardware, except a
> > > > microphone if you want sound.
> > > 
> > > In fact quite a number of the higher end USB cameras actually have
> > > an inbuilt microphone.
> > > 
> > > Also for those who have not heard about it, there is now a working
> > > open source USB over IP client and daemon
> > > 
> > >      <http://sourceforge.NET/projects/usbip/>
> > > 
> > > So with adequate bandwidth, it should be possible to use cheese,
> > > for example, to connect directly to a USB camera on a remote host.
> > 
> > USB 1.1 probably does not have adequate bandwidth.  Uncompressed 320x240
> > 24-bit video at 15 fps is 320x240x24x15 bits/sec = 76800x360 b/s =
> > 27648000 b/s = about 26 Mib/s.  USB 1.1 is (according to WP[1]) limited to
> > 12 Mib/s.  So either it needs some heavy duty compression, or lesser
> > video, or you can get a USB card.
> > 
> > [1] http://en.wikipedia.org/wiki/USB_1.1#Signaling
> 
> No idea what video format comes out of webcams but I've just been watching an 
> avi file over the network on my media player box, pulling the file from an NFS 
> share on linux and it's been playing 624x352 video @ 24 fps and the network 
> monitor shows it peaking at 1.6Mbps.

Fair enough.  12 Mib/s = 1.5 MiB/s, so drop it to 15 or 20 fps and it
might fit in USB 1.1.

-- 
There's a term for those who fantasize that the world works in
precisely the way that produces maximum convenience for them,
despite years of evidence to the contrary.  The term is "Morons".
          GA in <fp0m8j$lb0$1@reader2.panix.com>

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video capture H/W?? notbob <notbob@notbob.invalid> - 2011-05-27 21:07 +0000
  Re: video capture H/W?? Bill Marcum <bill@lat.localnet> - 2011-05-27 19:21 -0400
    Re: video capture H/W?? J G Miller <miller@yoyo.ORG> - 2011-05-28 14:32 +0000
      Re: video capture H/W?? ebenZEROONE@verizon.net (Hactar) - 2011-05-30 15:23 -0400
        Re: video capture H/W?? "Trevor Hemsley" <Trevor.Hemsley@mytrousers.ntlworld.com> - 2011-05-30 18:08 -0500
          Re: video capture H/W?? ebenZEROONE@verizon.net (Hactar) - 2011-05-30 19:20 -0400
            Re: video capture H/W?? J G Miller <miller@yoyo.ORG> - 2011-05-31 12:52 +0000
            Re: video capture H/W?? "Trevor Hemsley" <Trevor.Hemsley@mytrousers.ntlworld.com> - 2011-05-31 14:10 -0500
              Re: video capture H/W?? ebenZEROONE@verizon.net (Hactar) - 2011-06-01 00:32 -0400

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