[AG-TECH] Sony EVI-HD1 camera

Christoph Willing willing at vislab.uq.edu.au
Fri Mar 9 22:36:49 CST 2007

On 10/03/2007, at 4:55 AM, Bruce Curtis wrote:

> On Mar 9, 2007, at 8:55 AM, gurcharan khanna wrote:
>> All,
>> I think sending all stream types is a great idea, so the receiver  
>> can choose the resolutions
>> needed.
>> A related issue is bandwidth limitations. If I choose to receive  
>> 261 instead of HD for that
>> reason, then I may not be able to tolerate all those bits on my  
>> network. So, then the issue
>> becomes, how do I tell the source not to even send me the HD  
>> stream for instance but only
>> the 261 streams? If the HD and 261 are two separate modules, then  
>> that would work. If they
>> somehow are all integrated, maybe then that becomes a problem?
>> -gurcharan
>   Two ways to allow the receiver to choose between the streams  
> would be to
>     1. Send the streams in separate multicast groups.
>     2. Use Source Specific Multicast (SSM) and source the streams  
> from two different unicast source IP numbers.


Our current plan is to use the first of these methods that Bruce  
mentions. A twist on the AG toolkit's built in dynamic address  
allocation mechanism for new stream types makes this possible. Each  
new DV or HDV Producer is allocated a new multicast address. Any new  
DV or HDV Consumer is given a list of streams to choose from _before_  
subscribing to any of them.

That means that for DV & HDV, there'll be a separate vic instance for  
each video source being viewed (as distinct to the default H261 video  
services which show all available video sources for a venue in the  
same vic instance). This is all sort of working now, but there is a  
problem with VenueClients up to v3.0.2 not being updated with new  
stream information after initially entering a venue; that will be  
fixed for AG 3.1.


>> Christoph Willing wrote:
>>> On 09/03/2007, at 3:49 AM, John I Quebedeaux Jr wrote:
>>>> Someone asked me about this camera for HD use on the AG: http:// 
>>>> www.picturephone.com/products/sony_evi_hd1.htm
>>>> Anyone have any experience with it? I'm wondering if it was  
>>>> used, how to best "capture" it into a system for use on the  
>>>> AG... interest in using HD is high here. I'm more concerned  
>>>> about logistical issues with high resolution images on displays  
>>>> that don't have that much "resolution" space - particularly if  
>>>> several sites are involved.
>>> John,
>>> With regard to screen space logistics, we've developed a version  
>>> of vic that does DV and HDV - full details and perhaps a demo at  
>>> the forthcoming AG Retreat. One of the changes is the ability to  
>>> resize the video window(s) to any size you like. Thus you could  
>>> accomodate several streams at smaller than true HD size when  
>>> display space becomes tight.
>>> BTW, I think that when DV, HDV, HD are all more common in the AG,  
>>> best practice will be to always send those formats as duplicates  
>>> of standard H261 streams so that other sites can choose to view  
>>> their own preferred mix of H261 and higher resolution formats  
>>> (somewhat avoiding the screen real estate problem you raised, not  
>>> to mention bandwidth issues). The cameras we've been testing with  
>>> have a number of simultaneous outputs available so its trivial to  
>>> send both DV/HDV and H261 at the same time.
>>> chris
>>> Christoph Willing                       +61 7 3365 8350
>>> QCIF Access Grid Manager
>>> University of Queensland
>> -- 
>> -------------------------
>> Gurcharan S. Khanna, Ph.D.
>> Director of Research Computing
>> Office of the Vice President for Research
>> Director, Interactive Collaboration Environments Laboratory,
>> Center for the Advancing the Study of Cyberinfrastructure
>> ---
>> Rochester Institute of Technology
>> 1 Lomb Memorial Drive
>> Rochester, New York 14623-5603
>> Phone: 585-475-7504  ~  Cell: 585-355-1603
>> Email: gurcharan.khanna at rit.edu
>> Http:  www.rit.edu/~gskpop
> ---
> Bruce Curtis                         bruce.curtis at ndsu.edu
> Certified NetAnalyst II                701-231-8527
> North Dakota State University

Christoph Willing                       +61 7 3365 8350
QCIF Access Grid Manager
University of Queensland

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