Gurcharan S. Khanna gurcharan.khanna at rit.edu
Sun Dec 14 23:09:37 CST 2008


Really? Wow. You mean I can get vic to do uncompressed HD just like that?
I've spent months trying to get UltraGrid to work on Macs (I got it 
working on
colleagues machines but not mine!). But the goal was always to integrate 
it with
the AG later. If this could be done now..........hmmmmmm....that would 
be the
answer I've been waiting for.

So, can somebody kind do this quickly and let me try it out? I could 
get someone to do this but it would be from scratch in terms of their 
with this software.

If this works it would be so great and save so many hours of work for me.


Thanks so much!


Douglas Kosovic wrote:
> Hi,
>>>>> I, too, am extremely interested in vic supporting HD formats, 
>>>>> (including uncompressed!) One of the issues is the encoding 
>>>>> latency problem. Not sure there's a nice low latency encoding 
>>>>> solution out there yet. Alternatively, we might look at cheap 
>>>>> hardware encoders as the answer or HDMI cards to take the input 
>>>>> from the camera.
>>>>> Can vic be made to take the output of, say, the BlackMagic Design 
>>>>> HDMI card on a Mac?
> MacOS X UCL vic works out of the box with the BlackMagic Design HDMI 
> capture card, but gets scalled down to 640x480 for the large capture 
> option.
> A quick hack to add 1980x1080 support is to modify the following width 
> & height lines in video/grabber-macosx.cpp :
>    switch (decimate_) {
>                case 1: // full-sized
>                        width_ = SP601_NTSC_WIDTH;
>                        height_ = SP601_NTSC_HEIGHT;
> to:
>                        width_ = 1920;
>                        height_ = 1080;
> Windows UCL vic on the other hand crashes with the BlackMagic Design 
> HDMI capture card as it currently doesn't support the BlackMagic YUV 
> colorspace.
> I wouldn't mind adding support for USB HD camcorders that support UVC 
> (USB Video Class) H.264 streaming over USB, but I currently don't have 
> access to one. Note: Not all USB based camcorders support UVC (e.g. 
> Sony Hanycams).
>>>>> I am currently using AGDV under windows but would like to move to 
>>>>> linux and use the HDV/DV linux vic for the DV part; i don't think 
>>>>> it's encoding the HDV, just accepting it as input from the camera 
>>>>> already encoded??? [chris?]
>>>> It is possible to just packetise the compressed data from a camera, 
>>>> though as Chris points out it tends to have quite high latency. 
>>>> That is why the ultragrid and derivatives used uncompressed HD as 
>>>> their sources. VIC doesn't currently support mpeg2 nor does support 
>>>> packetisation of an existing compressed mpeg2 stream.
>>> wait, i thought chris' vic supported HDV, which i assume is mp4???
>> AFAIK most cameras support HDV - which is closely related to MPEG-2:
>> http://en.wikipedia.org/wiki/HDV#HDV_720p
> Mostly just the DV firewire based camcorders, the harddisk USB based 
> ones are now mostly AVCHD (MPEG-4 AVC/H.264).
>>> also, how hard/easy would it be for vic to support packetizing 
>>> uncompressed HD?
>> Not that hard - one needs to read the [RTP and codec] specs and code 
>> it up - or borrow someone else's....
>> Piers.
>>> :-)
>>> -gurcharan
>>>> Piers
>>>>> My ideal would be to encode the presenter's laptop output and 
>>>>> deliver that as just another video stream along side the 
>>>>> presenter's video and the audience video and have autoplace lay 
>>>>> them out nicely in a framed window, a la Adobe Connect or similar 
>>>>> products, so the presenter, the slides, and additional commentary 
>>>>> could be nicely recorded for later videoon demand playback.
>>>>> Just my opinion (and need),
>>>>> -gurcharan
>>>>> Piers O'Hanlon wrote:
>>>>>> Hi Derek,
>>>>>> In principle VIC should be able encode and decode HD video - 
>>>>>> using one of the codecs that support such resolutions e.g. H.264 
>>>>>> or h261as.
>>>>>> One needs to modify some of the configuration code in VIC to 
>>>>>> allow selection of larger resolutions (ie HD one needs something 
>>>>>> from 720p (1024x720) upwards). And of course an HD source is 
>>>>>> necessary. We don't currently have access to any HD kit so 
>>>>>> haven't had a chance to work on it but anyone is welcome to try!
>>>>>> Cheers,
>>>>>> Piers
>>>>>> 2008/10/22 Vine, Derek A <Derek.Vine at usd.edu>:
>>>>>>> Hello all,
>>>>>>> I am doing some research to spec. up a new AG room, and the 
>>>>>>> group with the money is interested in HD video.  I see that The 
>>>>>>> University of Queensland has an HDV/DV VIC for Linux based 
>>>>>>> systems already, but we would like to stay with Windows.
>>>>>>> I was just wondering what kind of time frame I can give them as 
>>>>>>> to when HD will be supported in AG on Windows.  In particular, 
>>>>>>> an HD VIC that will  take its video from a capture card with an 
>>>>>>> HD-SDI input, like the one attached in the PDF.
> I didn't see the PDF, what colorspace does it support? If it's YUV 
> 4:2:0, it would probably work with this vic:
> http://www.vislab.uq.edu.au/ag3/windows/vic-20081121.zip
> (which contained a fix for 480i DV white line artifacts)
> Anyway, I started working on adding support for more colorspaces to 
> the Windows code a few weeks ago and I might get back to working on 
> the code soon.
>>>>>>> Thank you in advance for your help.
>>>>>>> Derek Vine
>>>>>>> Communication Network Specialist
>>>>>>> The University of South Dakota
>>>>>>> 414 East Clark Street
>>>>>>> Vermillion, SD 57069
>>>>>>> (605) 677-8215
>>>>>>> dvine at usd.edu 

Gurcharan S. Khanna, Ph.D.
Director of Research Computing
Office of the Vice President for Research

Assistant Research Professor, Ph.D. Program
Golisano College of Computing and Information Sciences

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: 585-451-8370
Email: gurcharan.khanna at rit.edu

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