Hi Kevin,
besides Gallicaster, this is a general problem. Most Universities run i5
or i7 processor to capture sufficient framerates for 2-stream-recording.
So you have a trade off between CPU-Power and framerate (and some RAM) to
get a result that match with the needs of your institution.

Regards
Nils


> Hi Ruben,
>
> Thanks for the info, your approach sounds reasonable to me.
>
> I am still unclear on what hardware setup you are using. I found this
> page - http://wiki.teltek.es/display/Galicaster/Hardware+recommendations
> - so I am guessing you are probably running your captures against an
> Intel i3 processor with some sort of Hauppauge card.
>
> So in summary:
>
> a) using the above hardware setup, you had some video sync/dropped frame
> rate issues
> b) these issues were fixed with "a different pipeline structure with the
> element 'videorate' to guarantee the video stream synchronization"
>
> In theory, adding "videorate" to the MH capture agent pipeline should
> also fix this issue, but the placement of this element is probably key
> to the whole thing!
>
> Let me know if I got any of the above wrong.
>
>    Kevin Chan
>
>    Operations Team
>    Educational Technology Services
>    UC Berkeley
>
>
> On 2/6/12 4:51 AM, Rubén Pérez wrote:
>> Hi all,
>>
>> The pipeline we are using in Galicaster is rather different than the
>> one used in the standard capture agent in many ways, the first one
>> coming to my mind being the fact that Galicaster needs to provide
>> video feedback and the CA doesn't.
>>
>> Still, I will take a look and see if we can commit some changes to
>> improve the synchronization quality. I cannot guarantee though.
>>
>> The pipeline used is in the code of Galicaster, available at
>> www.galicaster.org <http://www.galicaster.org> .
>>
>> Sorry I cannot be more specific right now. When I have some spare time
>> I'll try to document myself on this topic and try to apply a patch
>> based on our research in Galicaster, if that's feasible without
>> altering the current CA pipeline too much. Does this sound reasonable?
>>
>> Regards
>>
>> 2012/2/2 Kevin Chan <[email protected]
>> <mailto:[email protected]>>
>>
>>     Hi Ruben,
>>
>>     Was this "fix" done against the referenced MH capture hardware or
>>     some other hardware setup?
>>
>>     In any case, thanks for the info, it would be great if you can
>>     provide this info for the MH developers in:
>>     http://opencast.jira.com/browse/MH-8505
>>
>>     Also, if you can provide the full pipeline structure, that would
>>     be great (for novice pipeline constructors like me).
>>
>>        Kevin Chan
>>
>>        Operations Team
>>        Educational Technology Services
>>        UC Berkeley
>>
>>
>>     On 1/30/12 5:38 AM, Tobias Wunden wrote:
>>>     Hi Ruben,
>>>
>>>     any chance that fix will make it back into trunk anytime soon? It
>>>     would have been great to have this in for 1.3 as well, given that
>>>     you seem to have sorted out that issue a while ago.
>>>
>>>     Tobias
>>>
>>>     On 30.01.2012, at 09:15, Rubén Pérez <[email protected]
>>>     <mailto:[email protected]>> wrote:
>>>
>>>>     Hi Kevin,
>>>>
>>>>     I can also confirm that we experienced the same frame drop/out
>>>>     of sync problem in long recordings, both in the capture agent
>>>>     and also in Galicaster's development stages. Finally, we
>>>>     discovered that the key was a different pipeline structure with
>>>>     the element 'videorate' to guarantee the video stream
>>>>     synchronization.
>>>>
>>>>     Maybe you could try and add this element to the CA's standard
>>>>     pipeline, and see what happens. Of course, you can also try
>>>>     Galicaster :)
>>>>
>>>>     Good luck
>>>>     Rubén
>>>>
>>>>     On 25 Xan, 2012 07:18, "Kevin Chan" <[email protected]
>>>>     <mailto:[email protected]>> wrote:
>>>>
>>>>         Hi all,
>>>>
>>>>         During preliminary testing of a 2h 15m capture (which we
>>>>         intend to post produce for YouTube), UC Berkeley discovered
>>>>         that the capture files for video and screen were off by 15m
>>>>         (with the screen capture via Epiphan being 15m short), which
>>>>         is more or less unacceptable to our post production folks
>>>>         (as it is very difficult for them to stitch this back
>>>>         together). This is likely to be due to dropped frame rate,
>>>>         but it is a bit difficult to confirm.
>>>>
>>>>         I am wondering if anyone else (besides Saskatchewan folks,
>>>>         who confirmed this issue) has encounter this issue and how
>>>>         they are working around it. I imagine that lowering
>>>>         framerates and bitrates would work, though some initial
>>>>         testing using various capture agent configurations seems to
>>>>         suggest that the capture files are still off by a few
>>>>         minutes even with the CPUs being not fully taxed.
>>>>
>>>>         We are using the reference capture agent hardware and very
>>>>         basic capture agent settings. This issue has been filed in
>>>>         MH Jira if anyone is interested:
>>>>         http://opencast.jira.com/browse/MH-8505
>>>>
>>>>         Finally, we have heard that there are various hardware and
>>>>         configuration setups for Matterhorn Capture Agents in
>>>>         production. I think it would be great if that we, as a
>>>>         community, can share this information (via the MH wiki) to
>>>>         help each other understand and learn about the various use
>>>>         cases and setups that are employed.
>>>>
>>>>         Thanks,
>>>>
>>>>         --
>>>>            Kevin Chan
>>>>
>>>>            Operations Team
>>>>            Educational Technology Services
>>>>            UC Berkeley
>>>>
>>>>
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