[AG-TECH] Re: Compiling VIC in Visual Studio 8 (2005)

George Estes gestes at ncsa.uiuc.edu
Fri Feb 2 08:38:59 CST 2007


  Being able to select which video streams to receive would definitely be helpful in our project to deploy PIGs to K-12 schools.  Many of these schools are bandwidth challenged.  We have been looking at ways to minimize bandwidth usage where needed and this would be excellent.

George

At 06:23 PM 2/1/2007 -0600, Piers O'Hanlon wrote:
>Hi,
>
>On 01/02/07, Joseph Stone <stone004 at umn.edu> wrote:
>>We've identified a need to have slow downlink participants be able to send
>>their video but not receive video.  The idea here being that high downlink
>>bandwidth participants will be able to see everyone who is participating.
>>It's not enough to just not display the video for slow downers, the bridge
>>needs to be told not to even send the stream at all.  It's enough for them
>>to be seen and for them to have two way audio (highly compressed - i.e.
>>GSM).
>>
>>
>>Is there a current version of vic that will fill the need?
>
>There are a few approaches that we may be able to take:
>
>1) Modify VIC so that it does not join the multicast group - thus it
>should only send traffic into the network and not receive any video
>traffic from external sources. I'm not sure if this will work (though
>it should in theory - We can test it..) but we could add this feature
>fairly easily.
>
>2) The following two options depend on having wide deployment of a
>newer version of Internet Group Management Protocol (IGMP) - Version
>3. Unfortunately I don't believe it is - though it is seeing wider
>deployment.
>
>2a) UCL vic has recently included a new feature that allows one to use
>Single Source Multicast (SSM) - Which needs to be started using a
>slightly different command line. For video reception a separate vic
>will need to started for each video stream wished to be received.
>
>2a) VIC could be enhanced to actually take advantage of some new
>features - namely source based filtering. which would allow one to
>choose which video srcs one wanted to see.
>
>3) Another approach would be to use a special gateway or relay that
>allows on to filter/choose the sources recieved - there are a few that
>have featured in various AG retreats.
>
>I'd would like to hear if others are interested in such functionality.
>
>Piers.
>
>>
>>Joe
>>
>>
>>On Jan 31, 2007, at 4:25 PM, Sam Gundry wrote:
>>
>>
>>Hi Socrates,
>>
>>
>>
>>
>>I actually commented out this line yesterday, before receiving this email.
>>:)
>>
>>
>>
>>
>>Video images now display locally in both the consumer and producer windows.
>>
>>
>>
>>
>>What should that line of code do? I haven't noticed anything out of the
>>ordinary yet...
>>
>>
>>
>>
>>Thanks,
>>
>>Sam
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>Socrates Varakliotis wrote:
>>
>>
>>Hi Sam,
>>
>>I assume you're still building Vic on Windows.
>>
>>Can you comment out line 562 in tcl/ui-main.tcl and rebuild?
>>
>>#$target enable_xv $enable_xv"
>>
>>Let me know what happens then.
>>
>>Thanks,
>>
>>--
>>
>>Socrates.
>>
>>----- Original Message ----- From: "Sam Gundry" <sgundry at vpac.org>
>>
>>To: <Andrew.Rowley at manchester.ac.uk>
>>
>>Cc: "Piers O'Hanlon" <p.ohanlon at cs.ucl.ac.uk>; <vic at cs.ucl.ac.uk>;
>>
>>"sumover-dev" <sumover-dev at cs.ucl.ac.uk>; <ag-tech at mcs.anl.gov>
>>
>>Sent: Tuesday, January 30, 2007 11:03 PM
>>
>>Subject: Re: [AG-TECH] Re: Compiling VIC in Visual Studio 8 (2005)




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