IEEE Spectrum July, 2012 - 20
hands on
Teleconferencing
on The cheap
With skype and a
little hacking, you can
teleconference with
a room full of people
A
s a telecommuter, I love
the Internet, for obvious
reasons. Strangely, though,
the teleconferencing system that IEEE
Spectrum editors have long been using
is just one step up from a speakerphone.
It only provides audio-and crummy
audio at that. As a consequence, every
editorial meeting I "attend" is a painful
experience: Imagine trying to pick
out a single voice at a noisy restaurant,
in the dark, while wearing earplugs.
A partial solution is to teleport
into meetings using Skype. Skype's
video capability gives you a window
on what's going on at the other end,
20
NA * iEEE SpEctrum * july 2012
which of course is nice. But the real
advantage is that it provides much
higher bandwidth audio than you get
over phone lines. That makes picking
out voices in a crowd much easier.
Using Skype on a laptop to attend
a meeting has some shortcomings,
though. One is the webcam's field of
view. Don't expect to take in much of
the room this way. Another is following
individual voices, which will vary in
volume and quality with how far away
the person is from the computer's
microphone. Both difficulties could be
overcome by connecting and controlling
multiple microphones and webcams.
And it turns out that with a modest
bit of hacking, you can do just that.
The key is that Skype conveniently
provides an application-programming
interface (API). With it, another
application can access many
of the Skype client's functions,
including its ability to select which
microphone and webcam are active.
Hearing aid: using Skype to
teleconference with a room full
of people works much better
when you're able to adjust which
microphone is live from the far end.
Image: DavID SchneIDer
My first attempt to use the Skype API
to pull together a cheap-but-effective
teleconferencing system used 10 separate
webcams, each with its own microphone.
I wrote a Windows program in C#,
which I dubbed MicPicker, to send
short text messages between two
computers during a Skype session.
Based on what message is received, this
software selects which webcam and
microphone the Skype client uses. So
with this program running at both ends,
a remote attendee can choose which
webcam and mic will be live during
a meeting, changing that selection on
the fly to follow the conversation.
Buying 10 webcams can get pricey,
though. I wanted the system to be
inexpensive, but I also wanted the
spectrum.ieee.org
http://spectrum.ieee.org
Table of Contents for the Digital Edition of IEEE Spectrum July, 2012
IEEE Spectrum July, 2012 - Cover1
IEEE Spectrum July, 2012 - Cover2
IEEE Spectrum July, 2012 - 1
IEEE Spectrum July, 2012 - 2
IEEE Spectrum July, 2012 - 3
IEEE Spectrum July, 2012 - 4
IEEE Spectrum July, 2012 - 5
IEEE Spectrum July, 2012 - 6
IEEE Spectrum July, 2012 - 7
IEEE Spectrum July, 2012 - 8
IEEE Spectrum July, 2012 - 9
IEEE Spectrum July, 2012 - 10
IEEE Spectrum July, 2012 - 11
IEEE Spectrum July, 2012 - 12
IEEE Spectrum July, 2012 - 13
IEEE Spectrum July, 2012 - 14
IEEE Spectrum July, 2012 - 15
IEEE Spectrum July, 2012 - 16
IEEE Spectrum July, 2012 - 17
IEEE Spectrum July, 2012 - 18
IEEE Spectrum July, 2012 - 19
IEEE Spectrum July, 2012 - 20
IEEE Spectrum July, 2012 - 21
IEEE Spectrum July, 2012 - 22
IEEE Spectrum July, 2012 - 23
IEEE Spectrum July, 2012 - 24
IEEE Spectrum July, 2012 - 25
IEEE Spectrum July, 2012 - 26
IEEE Spectrum July, 2012 - 27
IEEE Spectrum July, 2012 - 28
IEEE Spectrum July, 2012 - 29
IEEE Spectrum July, 2012 - 30
IEEE Spectrum July, 2012 - 31
IEEE Spectrum July, 2012 - 32
IEEE Spectrum July, 2012 - 33
IEEE Spectrum July, 2012 - 34
IEEE Spectrum July, 2012 - 35
IEEE Spectrum July, 2012 - 36
IEEE Spectrum July, 2012 - 37
IEEE Spectrum July, 2012 - 38
IEEE Spectrum July, 2012 - 39
IEEE Spectrum July, 2012 - 40
IEEE Spectrum July, 2012 - 41
IEEE Spectrum July, 2012 - 42
IEEE Spectrum July, 2012 - 43
IEEE Spectrum July, 2012 - 44
IEEE Spectrum July, 2012 - 45
IEEE Spectrum July, 2012 - 46
IEEE Spectrum July, 2012 - 47
IEEE Spectrum July, 2012 - 48
IEEE Spectrum July, 2012 - 49
IEEE Spectrum July, 2012 - 50
IEEE Spectrum July, 2012 - 51
IEEE Spectrum July, 2012 - 52
IEEE Spectrum July, 2012 - 53
IEEE Spectrum July, 2012 - 54
IEEE Spectrum July, 2012 - 55
IEEE Spectrum July, 2012 - 56
IEEE Spectrum July, 2012 - 57
IEEE Spectrum July, 2012 - 58
IEEE Spectrum July, 2012 - 59
IEEE Spectrum July, 2012 - 60
IEEE Spectrum July, 2012 - Cover3
IEEE Spectrum July, 2012 - Cover4
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