[linux-audio-user] LAC Recording Guidelines
nettings at folkwang-hochschule.de
Mon Mar 5 11:56:14 EST 2007
> ES> It would be nice with some recording guidelines for LAC. Both for
> ES> video and for audio.
well, for the speakers:
* it is not necessary that your slides be readable on our video stream -
as marije pointed out, downloadable versions will be available. *but*:
it would be helpful if your slides were visually distinct enough that
video stream watchers can figure which slide is currently up (biggish
headlines usually work well, and nobody has ever been dragged from stage
for showing nice illustrations...)
* the video image would benefit greatly from dark-background slides -
this would avoid the speaker getting drowned in darkness when the camera
exposure corrects for the bright projection. (not a problem if we have
stage lighting for the speaker, but that is unlikely.)
* if by luck stage lights are indeed available at and near the
lecturer's desk - stay within their range :)
* use a traditional pointer or a large laser pointer. very small red
dots tend to get lost in low resolution and encoding artifacts...
we will try to have fixed camera positions this year or tune the codecs
to avoid massive bandwidth surges.
regarding the combination of slides and audio/video, the mostest
niftiest solution would be to have annodexed ogg streams, but this is
not going to happen unless somebody volunteers as a full-time anodex
editor during the conference and can set up the necessary toolchain
him/herself. regrettably, my annodex knowledge is still limited to what
conrad and silvia of csiro taught me 3 years ago at the LAC...
as to multiplexing:
the problem is that the toolchain we used last year
(dvgrab|ffmeg2theora|oggfwd) relies on a dv stream with audio in it.
that means that unless we get our hands on very professional camera
equipment with external audio ins, the sound has to come from the
build-in cam mike (the line ins of consumer-grade cams suck to the point
of being completely unusable).
the only toolchain i'm aware of that allows for flexible muxing of audio
on video after grabbing is flumotion, but i've had mixed results with
that in terms of stability. if it can be made to work, that would be my
lastly, getting a good sound depends on whether we have the technical
equipment and necessary cabling to tap into the conference mixers.
should not be a problem, but has not been checked yet.
fwiw, i'll be dumping stream-related info at the lac wiki:
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