On Fri, Jul 29, 2011 at 07:30:21PM -0500, Edgar Aquino wrote:The debconf-video software stack consists of two main components:
> which software is used for stream the DebConf11?
> if is freely/libremente available, i want to test it local and may be use it
> for educational purposes in the web.
dvswitch, and icecast.
DVswitch is an application that can be used to take a DV stream from a
video camera (as produced by some consumer video cameras over FireWire),
and with which one can select which camera stream to send to the output
stream 'live', i.e., without post-processing. For more information, see
<http://dvswitch.alioth.debian.org>. DVswitch can produce a stream for
recording (with 'dvsink-files') and one for streaming (with
'dvsink-command') at the same time, so the video that is streamed live
over the Internet is recorded for future reference at the same time.
What happens with the stream that goes over the Internet is totally out
of scope for DVswitch. We use icecast with ffmpeg2theora to encode, but
it is perfectly possible to use something else, provided the software
you use has a helper application that will accept a DV stream on
standard input, transcode it, and send it off to the streaming server.
For the DVswitch machine, you need a fairly powerful machine, since it
> What kind of requirements are needed? [machine, server, client, kind of
> cameras, storage, connection speed...]
needs to decode several DV streams in parallel, and may have some
additional computational requirements if you want to use some of the
effects that DVswitch supports (like picture-in-picture, or fade
transitions in the newest development release). In my experience, any
2Ghz or better machine will suffice, however it may be possible that
slightly slower machines will work too; you may have to experiment
there.
It is recommended that you do not transcode the stream on the DVswitch
machine, since that will take away precious computing time. The machine
doing the transcoding will also require a somewhat powerful processor.
How powerful exactly depends on the codecs you wish to use.
If you wish to use more than two or three cameras and also wish to do
live streaming, you need a gigabit network; DV streams take about
25-30Mbit/s of data, so will clog your network if you use more than 3
streams over a 100Mbit network (and up to the transcoder, the output
stream is also a DV stream).
You will need cameras that produce a DV stream. Any camera with a DV
tape deck and firewire output can do this. For each camera, you will
also need a computer or laptop with firewire port. Note that these
laptops can be rather slow, provided they have a gigabit port; the
processor requirements on the dvsource laptops are very low. It is safe
to use the laptop on which dvswitch runs as one to which you connect a
camera.
For storage, you'll need about 13GB per recorded hour.
> **Sorry if my english is wrong, i'm not very skilled on writting.....
That's okay, it's better than my spanish :-)
Hope this helps,
--
The volume of a pizza of thickness a and radius z can be described by
the following formula:
pi zz a