[AG-TECH] Release of AGVCR - recording AG sessions

Derek Piper dcpiper at indiana.edu
Thu Nov 10 11:25:50 CST 2005


	Hi,

	Yes, I should probably note that problem in the 'known issues' stuff. 
Problem is I wrote a lot of this code a few months ago and only just 
recently did the website, so in testing with all of you fine folks I'm 
saying 'oh yea!' and trying to catch up on the documentation ... oops :)
	Now, you *should* be able to immediately play back to the same venue 
you recorded from, while the AGtk VIC and RAT are running. This is true 
when AGVCR is running from Linux. It allows this because AGVCR is 
altering the SSRCs in every packet sent out on playback, thus since it 
appears to VIC and RAT as if new sources have 'appeared', then all works 
as it should. Under Windows I found that if I enabled this 'packet 
munging' for audio streams then it resulted in no audio being played at 
all - regardless of venue, whereas under Linux it worked fine. I will 
reinvestigate this but under Windows builds it's disabled for audio 
streams since the behavior was deemed 'unreliable', and I wanted to be 
sure that in both builds the  stream output worked for most cases where 
a recording is played back at a different time from the original.
	In your test here, it would work in the same venue if participants 
reloaded the venue, since then VIC and RAT would choose new SSRCs for 
their packets and everyone would be happy. The garbled audio in this 
case is from more than one source having the same SSRC, which is against 
the spec, i.e. bad.

	Derek

Wachtel, Robert L wrote:
> I just completed a test session with the folks at ANL. Recording worked
> well. Playback did not do so well until I switched venues from the one
> in which I made the original recording. Playback then worked well. Just
> as with recording playback does require you to have a multicast session
> active and join into the multicast group with the configuration in
> AGVCR.
> 
> Playback while still in the original venue caused broken audio from the
> other remote sites and I could not hear any of the playback audio though
> I could see the video playback as well as the continuing live video.
> 
> This is on a Windows XP Pro SP2 in multicast.
> 
> Bob W.
> 243-2857
> 
> -----Original Message-----
> From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov] On
> Behalf Of monika.k.rabarison at ccaix.jsums.edu
> Sent: Thursday, November 10, 2005 9:42 AM
> To: Nagykaldi,Zsolt F. (HSC); dcpiper at indiana.edu
> Cc: Access Grid Technical mailing list
> Subject: RE: [AG-TECH] Release of AGVCR - recording AG sessions
> 
> Also, when I start agvcr from the command line and play back
> the recorded file, vic and rat start but showing the current
> video and audio in the venue, instead of the recorded ones. 
> 
> 
>>Hi All,
>>
>>I am currently trying it on XP Pro SP2 with multicast.
>>Recording seems to work fine (the file got some size).
>>When playing back, I don't see vic and rat starting.
>>
>>I am not sure what I am doing wrong. Attached is a
>>snaphot. Note the "File Offset: .....out of 0 bytes" ????
>>
>>TIA
>>Monika
>>
>>
>>
>>> 
>>>Win XP Pro SP2. Works like a charm in multicast.
>>> 
>>>Zsolt
>>> 
>>> 
>>>_ _ _
>>> 
>>>Zsolt Nagykaldi, PhD
>>>Research Associate, Clinical IT Specialist
>>>University Of Oklahoma Health Sciences Center
>>>Department Of Family And Preventive Medicine
>>>Oklahoma Center For Family Medicine Research
>>> 
>>>900 NE 10th Street
>>>Oklahoma City, OK 73104
>>>Phone: (405) 271-8000 Ext.:1-32212
>>>Fax:     (405) 271-1682
>>>
>>>________________________________
>>>
>>>From: dcpiper at indiana.edu [mailto:dcpiper at indiana.edu]
>>>Sent: Wed 11/9/2005 7:07 PM
>>>To: Nagykaldi, Zsolt F. (HSC)
>>>Cc: Access Grid Technical mailing list
>>>Subject: RE: [AG-TECH] Release of AGVCR - recording AG
>>>sessions
>>>
>>>
>>>
>>>
>>>Hi Zsolt,
>>>
>>>Yea, that's one thing noted in the 'known issues', the
>>>problem with recording from unicast. I'm glad to hear
>>>AGConnector helped, I like that program. There's some
>>>old code in there that I wrote for trying to send data
>>>to QuickBridge (since it seems to need to receive
>>>something in order to send data back to you) but I never
>>>did get it working to any satisfaction.
>>>
>>>Since I'm replying to all I was aware (as is typical
>>>after announcing something works) that under Windows now
>>>it appears to have problems with reading or displaying
>>>the file length, something for me to look at tomorrow.
>>>
>>>Growing pains I think, I've been rewriting a lot of it
>>>(under Linux for the most part) in the last few weeks as
>>>I've considered more things that I wanted to add, and lo
>>>today I 'got the nod' to release it. So I thought I'd
>>>let everyone take a look instead of me sitting on it a
>>>moment longer. This may be good and bad, but as long as
>>>everyone treats it as 'alpha' for now until more testing
>>>is done then I think we'll all be good. I do not think
>>>the file format will need to change, given all that I
>>>have in my 'future plans', so any recordings made now
>>>will work in later versions. If for some reason it does,
>>>I will make available the converter program I have used
>>>to convert previous recordings to the new format.
>>>
>>>Thanks for trying it out, incidentally, what version did
>>>you use, Windows or Linux?
>>>
>>>Derek
>>>
>>>Quoting "Nagykaldi, Zsolt F. (HSC)"
>>><Zsolt-Nagykaldi at ouhsc.edu>:
>>>
>>>
>>>>Fantastic Derek, thanks! One thing. In bridged unicast
>>>>the recorder can not establish connection with the IPs
>>>>and ports listed. However, in multicast (even with the
>>>>AG Connector) it rocks! 
>>>>Zsolt
>>>>
>>>>
>>>>_ _ _
>>>>
>>>>Zsolt Nagykaldi, PhD
>>>>Research Associate, Clinical IT Specialist
>>>>University Of Oklahoma Health Sciences Center
>>>>Department Of Family And Preventive Medicine
>>>>Oklahoma Center For Family Medicine Research
>>>>
>>>>900 NE 10th Street
>>>>Oklahoma City, OK 73104
>>>>Phone: (405) 271-8000 Ext.:1-32212
>>>>Fax:     (405) 271-1682
>>>>
>>>>________________________________
>>>>
>>>>From: owner-ag-tech at mcs.anl.gov on behalf of Derek
>>>>Piper Sent: Wed 11/9/2005 2:57 PM
>>>>To: Access Grid Technical mailing list
>>>>Subject: [AG-TECH] Release of AGVCR - recording AG
>>>
>>>sessions >
>>>
>>>>
>>>>
>>>>        Hi all,
>>>>
>>>>        I'm happy to announce that finally I've been
>>>>given the go-ahead to release AGVCR to the community.
>>>>It was a program I started writing around January and
>>>>it was ready for release in a workable incarnation
>>>
>>>some time in June. However, due to possible 'intellecual
>>>
>>>>property' concerns from 'those that deal with those
>>>>things' at IU, I was unable to release it back then. I
>>>>declined to mention it to the community at large until
>>>
>>>this release so as not to 'tease' people with a product
>>>
>>>>they could not get. I won't get into griping about
>>>>that on this list :> Some of you have known about this
>>>>program earlier since we have had AccessGrid meetings
>>>>that I have recorded. For those parties concerned, we
>>>
>>>can communicate off-list on the best way to get the
>>>
>>>>        recordings to you. AGVCR is a program to
>>>>record and play back the RTP/RTCP stream that an
>>>>AccessGrid conference uses. The amount of data it
>>>>gathers is certainly non-trivial, a few hours of
>>>>recording with a number of participants can easily
>>>>reach a few gigabytes in size. Timing and minimal
>>>>        overhead information is embedded in the file
>>>
>>>for accurate playback. The website for the project is
>>>
>>>>       here: > 
>>>
>>>http://iri.informatics.indiana.edu/~dcpiper/agvcr/ >
>>>
>>>>        I invite anyone interested to take a look,
>>>>download and use it to see
>>>>what you think. I welcome feedback, please bear in
>>>>mind though that it is still being actively worked on.
>>>>A number of changes have been made of late, so testing
>>>>has not been as extensive as it probably should  be,
>>>
>>>but that's another reason to get it out there. The
>>>
>>>> website has source for Linux/Unix and a precompiled
>>>>binary for Windows. I may add pre-compiled binaries
>>>
>>>for popular Linuxes if there is interest. >
>>>
>>>>        Thanks,
>>>>
>>>>        Derek
>>>>
>>>>--
>>>>Derek Piper - dcpiper at indiana.edu - (812) 856 0111
>>>>IRI 323, School of Informatics
>>>>Indiana University, Bloomington, Indiana
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
>>> 
>>
>>
>>[Attachment: agvcr.jpg] 
> 
> 
> 

-- 
Derek Piper - dcpiper at indiana.edu - (812) 856 0111
IRI 323, School of Informatics
Indiana University, Bloomington, Indiana




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