[AG-TECH] Sony EVI-HD1 camera

Christoph Willing willing at vislab.uq.edu.au
Fri Mar 9 23:06:00 CST 2007

On 10/03/2007, at 1:11 AM, John I Quebedeaux Jr wrote:

> Christoph,
> I think the demo would be good to see.  I agree with your thought  
> there - until there is such thing as more bandwidth than we can  
> fill up there will be sites with constraints and the ability to  
> choose which versions of which streams (high vs low resolution/high  
> vs low bandwidth) having those choices is a good thing.
> To address having multiple versions of streams and sites not having  
> the bandwidth, break them up into different groups (multicast  
> addresses). Say, you only want the h261 streams - that's one group.  
> DV... HD... HDV other groups. You only "get" a group if you  
> "connect" to it... etc. of course, then we start actually using  
> groups! and then we're back to the issue of multicasting. That's  
> still a problematic issue in my state, but i'm chipping away at it.  
> With all the video being tossed around these days, i have to think  
> even regular ISP's are thinking multicast thoughts... no?


Because the multicast address allocation mechanism we're taking  
advantage of is built into the AG toolkit itself, unicast versions of  
any of these streams should be available via AG3 bridges. Take pity  
on sites running bridges!

> lately the ability to do HD at the same time is foremost in  
> everyone's request. For me, besides the cost, it's the ability to  
> just "make it work" and the realization that I'm now using  
> projectors that are 4-5 years old and folks don't seem to  
> understand that resolution and screen "space" are two different  
> things. The ability to scale video to any size (and save/store  
> those settings as well - etc) would be ideal.... i've always  
> pointed out how flexible the AG ultimately is because it is a toolkit.

Its often possible to use new possibilities or features, in this case  
DV/HDV, to drive infrastructure upgrades. Its pretty clear that  
you're less able to take advantage of multiple DV/HDV streams without  
appropriate display equipment; same goes for the network. If people  
really want this feature, they could/should/will eventually be your  
allies in upgrading the infrastructure to support it.


> -John Q.
> -- 
> John I. Quebedeaux, Jr.; Louisiana State University
> Computer Manager LBRN; 131 Life Sciences Bldg.
> e-mail: johnq at lsu.edu; web: http://lbrn.lsu.edu
> phone: 225-578-0062 / fax: 225-578-2597
> On Mar 8, 2007, at 10:23 PM, 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

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

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