--- Forwarded Message from "Dente, Ed" <[log in to unmask]> ---
>From: "Dente, Ed" <[log in to unmask]>
>To: Language Learning and Technology International Information Forum
<[log in to unmask]>
>Subject: RE: #7476 Videoconferencing Equipment Testing
>Date: Mon, 5 Apr 2004 10:51:22 -0400
>From: Michael Heller <[log in to unmask]>
Dear LLTI listserve readers,
Over the summer I will be purchasing a set-top videoconferencing (VC)
unit for use by Montclair's foreign language and linguistics programs.
I have lined up demo units from major vendors (Polycom, VCON, Tandberg,
and Sony) and, during late April and early May, I wish to test these
units prior to selecting a model. If you have any VC equipment
available and are willing to help me test with a short 5 minute VC,
please contact me off list. I am particularly interested in
simultaneous VC with multiple sites, in VC with sites in Europe, South
America, Africa, the Middle East and Asia, in VC that includes data
sharing, in VC that includes a webcasting option, as well as in VC with
those directly connected to Internet2.
Kindest regards,
M
I have a Polycom Via-Video at my computer that I will be happy to use
conference if you'd like to test similar equipment. Let me know when.
The reason I am replying to the whole list on this is that I have further
videoconferencing information that I think may be of use to those who use
videoconferencing in their teaching. It is a cool technical fix for that
serious problem we all have with video/audio lag. I received it from a
colleague, and I have found it to be very helpful in the two Tandberg
Educator systems I oversee.
Cheers,
Ed Dente
Please see below:
There have been a number of discussions about the occasional "lip synch"
problem in video conferencing. The problem is that in some cases the video
is delayed longer than the audio, so voices are heard before the speaker's
lips are seen to move. Crudely speaking, this is caused by the fact that the
video information is more voluminous than the audio information, and hence
is delayed by overloaded components along the way, such as network devices
and MCUs. There is no inherent synchronization built in, so in a non-ideal
world, things tend to become unsynchronized.
There is usually no "knob" or setting one can manually adjust to compensate
for this. So this leads to either just accepting it, or looking for more
unusual solutions.
At the recent ViDe conference in Indianapolis, this topic was discussed, and
a new approach was suggested. I have investigated this new approach further
and found that it may be a solution.
The basic idea is that the audio needs to be delayed with respect to the
video, so as to bring them back into synchronization. It turns out that
people can learn to do this with a little effort.
All you have to do is move your lips before you actually speak. This is a
form of ventriloquism, and it has been taught for some time at the Edger
Bergen Institute for Advanced Speech.
In traditional ventriloquism, you shift your speech to another location. But
in this case, you shift it to another time. In mathematical terms, the
first case deals with the spatial domain (often involving the spatial
Fourier Transform), and the second one with the time domain (where it is
described by the McCarthy Transform).
I have been studying this new technique via a correspondence course from the
EBIAS, and have achieved a modest degree of skill, as of April 1. I can
demonstrate it for you some time in a video conference, or maybe in next
year's Megaconference.
Robert S. Dixon, Ph D, PE
Chief Research Engineer
Ohio Academic Resources Network (OARNet) and Ohio State University, Office
of the CIO
(Too bad I missed April Fools Day with this!)
Cheers!
Ed
======================================================
Edmund N. Dente
Director, Language Media Center
Asst Director, Media Services 617.627.3036
TuftsUniversity [log in to unmask]
Medford, MA 02155 http://ase.tufts.edu/lmc
-----Original Message-----
From: LLTI-Editor [mailto:[log in to unmask]]
Sent: Monday, April 05, 2004 10:36 AM
To: [log in to unmask]
Subject: #7476 Videoconferencing Equipment Testing
--- Forwarded Message from Michael Heller <[log in to unmask]> ---
>From: Michael Heller <[log in to unmask]>
>Subject: Videoconferencing Equipment Testing
>Date: Sat, 3 Apr 2004 12:03:59 -0500
>To: LLTI-Editor <[log in to unmask]>
M
--
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Michael Heller
Director of Language Learning Technology
College of Humanities & Social Sciences
Montclair State University
1 Normal Ave (CHSS/DI-287B)
Montclair, NJ 07043-1699
973-655-7504 Voice
973-655-4060 Fax
[log in to unmask]
http://alpha.montclair.edu/~hellermd/
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