Wireless Live Video Streaming From Desktop Computers Using Sorenson Broadcaster.
John C. Pearson,
Gary L. Nieder, and Mark Anderson
Department of Anatomy, Wright State
University, School of Medicine
Abstract:
A key component of neuroscience
education is the use of patients to demonstrate neurologic disease. Patient demonstration provides opportunity
to teach physical examination technique, and to observe movement abnormalities
associated with nervous system disorders.
In a vertically integrated neuroscience curriculum, clinical principles
are introduced in introductory level courses, resulting in a greater demand for
patient use in the “preclinical” classroom environment. With increased patient involvement, however,
comes increased problems with patient accessibility. A solution to the problem of accessibility is to be able to show
patients live, in the clinic, to a classroom of medical students. Remote broadcasting of live video promises
to give clinicians this capability. Use
of wireless remote broadcasting enables even more flexible scenarios such as
the participation of an entire classroom in the patient rounds experience. We will demonstrate several hardware and
software configurations currently available.
In the present project we will demonstrate
the creation and delivery of live video streams using two different capture and
delivery configurations. The first will
involve video input through an ixTV PCI card in a 400MHz Macintosh G3 desktop
computer. This computer will broadcast
through a direct ethernet connection to "online" playback
machines. The second configuration will
demonstrate video input through a PC capture card (Irez, CapSure) to a
Macintosh G3 PowerBook. This computer
will broadcast live video streams through a wireless LAN card to a base station
port for ethernet distribution.
Consequently, this set-up will enable wireless remote transmission of
the video stream from any location within the demo area.
Several broadcast scenarios within
Sorenson Broadcaster (1.0) will be demonstrated: Unicasting to a single
recipient; Multicasting without a replication server; and Broadcasting using a
replication server. Unicast streams go
to individual IP addresses and are consistently transmitted through Internet
routers and firewalls. Multicast video
streams go to multiple registered recipients within a local area network. This protocol optimizes bandwidth
consumption within that network.
Broadcasting using a replication server involves sending a unicast
stream to a replication server (located at Wright State University) which will
then replicate the incoming stream as many unicast streams that may be
successfully transmitted through routers and firewalls on the Internet.
Remote broadcasting of live video will
allow clinicians to present a greater variety of teaching cases to students in
traditional classroom settings. It will
also allow interaction between students, physicians, and patients during the
learning experience. The live
presentations may also be recorded for individual student review at a later
time. These features make live video
streaming the ideal complement to the use of in-class patient demonstrations
and archived streaming video in the vertically integrated Medical Neuroscience
curriculum
Our original idea was to allow people to
see the wireless roadcast of live video streams in action. We are planning to
do this by having a remote crew (eg. Gary Nieder and Mark
Anderson), with video camera and
broadcast computer, roving around the demo area broadcasting to a playback
machine located at our assigned station in the demo area. With this set up,
interested attendees would have opportunity to examine, first hand, both ends
of the broadcast process. They would be
able to evaluate the quality of the streams, and get an appreciation for the
physical limitations of the hardware involved, especially the airport card and
base station. We could demonstrate several of the broadcast scenarios of which
Sorenson Broadcaster is capable.
We selected to do a demonstration because:
(1) In a platform talk there would be very little time available to actually
demonstrate the live broadcast. And
that broadcast would probably show only one of the variety of scenarios
available through Sorenson Broadcaster.
For example we would not have time, during the presentation, to
establish a 'reflected broadcast' using our OS X server at WSU. (Plus, there
would be little time to achieve optimal streaming quality by adjusting
broadcast parameters to match the internet transmission speed at that moment). (2) With a platform presentation, the
audience would not be able to develop an appreciation for the relationship
between the remote broadcast unit (i.e., video camera, portable computer with
aircard) and the base station hook up. (These would likely be remotely located
outside of the presentation room). This
'hands-on' experience is the best way to evaluate the quality of the video
streams and see the other physical limitations of both hardware and software.
Benefit in Attending
Session:
Participants will learn to: capture live video and broadcast it in video streams using a Mac G3 desktop computer with a conventional T1 cable hook-up; capture live video using a Mac G3 PowerBook and broadcast it using wireless LAN technology; learn how wireless remote live video broadcasting may benefit clinical instruction in the classroom setting.
John C. Pearson, Ph.D.
Department of Anatomy
Wright State University
School of Medicine
Dayton, OH 45435
Telephone Number: 937-775-3212
Fax Number: 937-775-3391
E-mail Address: john.c.pearson@wright.edu
Web Site: http://www.neuro.wright.edu/sol99/01title.html
CO-AUTHORS' INFORMATION
Gary L. Nieder, Ph.D.
Mark Anderson, B.T.
GLN
Department of Anatomy
Wright State University
School of Medicine
Dayton, OH 45435
MA
Interdisciplinary Teaching Labs
Wright State University
School of Medicine
Dayton, OH 45435
Telephone Number(s):
GLN: 937-775-2547
MA: 937-775-4563
Fax Number(s):
GLN: 937-775-3391