[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.
Gurcharan,
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.
chris
>> 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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