Converting a Desktop Video Conferencing System to Classroom Use
Liz Johnson


Abstract

An inexpensive desktop video conferencing system can be converted for use in a classroom with software upgrades and hardware additions. Improvements in features and performance have occurred in this technology over the past year which make this possible. Students can interact with a remote instructor by audio, video, and keyboard. Certain patterns of room layout maximize the possibilities.


Converting a Desktop Video Conferencing System to Classroom Use

Desktop Video Conferencing (DVC) was conceived to transfer audio, video, and data in a business environment from one individual work station to one other. Educators thought that there must be a use for DVC in their environment as well. Some schools began trying it out for advising, testing, or placement. Almost in the same breath that advocates praised the potential of the technology it was also judged inadequate. "This would really be great if...the video were better... the audio were better...it could multi-point...the screen was bigger." In an effort to bring the costs down educators asked "How could it be used more often to benefit more students?" The obvious use is course delivery, but DVC would be incredibly expensive if it could only be used with individuals either on an individual studies basis or in a classroom with individual workstations. It would be a very inexpensive tool if somehow it could be used with groups of students.

The subject of this workshop deals with the question of how to convert a technology that was intended for individual use in a business, to group use in education. Fortunately, the demands of business have benefited education as well. Education can take advantage of many of the advances that have occurred over the last year to make DVC more responsive to the needs of business. For example, it was thought originally that fast, smooth video was not necessary for DVC because the picture was so small. However, the quality of broadcast television has spoiled the consumer. He doesn't know why the picture and audio are better on his tv at home nor does he care. He simply demands the same quality whether it is carried by cable, satellite or telephone line. Industry responses to this and other demands are making DVC more viable in the classroom. There is every reason to believe that these improvements will continue.

Software Upgrades

MTSU bought a ProShare Personal Video Conferencing System 200 in 1995. A few months later we received a free upgrade. In 1996 we purchased version 2.0. It proved to be a dramatic improvement in many ways. Motion was smoother. Picture quality was better. The interface was easier to use. It included a choice of built in links to multipoint service providers.

Hardware Additions

Because we wanted a larger picture we purchased a PCI board which would produce full screen video at a single mouse click. However, the ATI version that we bought was difficult to install and is not Windows 95 compatible. Intel recommends other PCI boards. These are listed in the ProShare ReadMe file.


Originally we tried connecting the DVC system to a 27" NTSC monitor through a scan converter. However the picture quality proved unsatisfactory. We now intend to use a 27" SVGA monitor instead and expect a much better result. Although the cost of an SVGA monitor this size is quite high, the improved picture is worth it.


Due to the upgrade to 2.0 it was recommended that we add 8 mgs of RAM. This was a quick and inexpensive addition.


For full duplex audio in the classroom we purchased a US Robotics ConferenceLink Performance Telephone with two extensions. Students in different classrooms will be able to share audio without having to operate individual microphones.


We plan to install the DT-100 AF compact Elmo document video camera to the S-video output of the ProShare card through a scan converter to give instructors the ability to show documents and specimen from a second camera. Either this camera or the ProShare camera will be able to rotate to show a view of the classroom A major limitation of a DVC system is that it has only two camera ports. The Elmo will also allow the instructor to use presentation software such as PowerPoint for displaying information. This will compensate for loss of ProShare's main distinguishing advantages when transmitting between a ProShare and a room system: its flexible white board and its ability to share documents and applications. The Elmo can also add extra video ports for more cameras if necessary.

Improvements in Features

Some new features have been long awaited such as the use of industry wide standards. ProShare 2.0 has added three new standards to be compatible with a range of other systems. H.320 is the universal video conferencing standard. T.120 is the standard for data conferencing. Digital SVD (Digital Simultaneous Voice and Data) is the standard for conferencing over phone lines.
Multipointing is another long awaited feature. ProShare 2.0 allows calls over ISDN, networks, or modems. On ISDN several callers can connect simultaneously. On network calls, up to 5 participants can share data. Voice contact must be made over a phone line. Modem connections allow video to one other person over phone lines.
Other features are less anticipated but none the less welcome. The video windows can be arranged in a variety of ways to maximize screen space including picture-in-picture. Business cards allow multiple participants who are data conferencing to see pictures of each other. The Photo Exchange allows participants share still photos. A Participants Bar shows the names of all participants. A Turntaking button prevents ìcursor wars.î

Improvements in Performance


Version 2.0 has enhanced video resolution and motion. But because more information is expected to go through the same lines ProShare asks the user to make a choice. Do you prefer better video or smoother motion? The user can switch between these options under Video Preferences in the Tools menu. When a still object or document is being shown, a better picture might be preferred. When a procedure is demonstrated, a smoother motion can be chosen. It is not necessary to constantly switch between these options but when one or the other can make a difference the option is available.

Room Layout

Room layout is just as important, if not more so, when planning to use DVC in a classroom as it is when using a room system. Acoustic ceiling tiles and carpeting are essential. Acoustic wall tiles may also prove necessary. DVC is a small system intended for close-up contact. It should not be used in an open room or in a room that is too large. It should also not be used in a noisy environment. A small class of from five to fifteen students is preferred. This is the usual size of most of our rural distance learning classes. Because of the need to use a ConferenceLink phone instead of individual mics, students will be arranged around both sides of long tables placed in a U shaped arrangement. This will insure that all the students will be close enough to the ConferenceLink phone.

Expectations

Although we have not yet used DVC for course delivery in a classroom, we have tested all the components and trained teachers in its use. Both the teachers and Continuing Studies are confident that DVC will be able to perform adequately. We expect that, whereas the video may still be slower and have less resolution than a room sized compressed video system, it will be adequate. We expect the audio in this particular room to be a little strained, but that in a smaller setting, as we intend to use it in the future, it will work satisfactorily. We expect that the teachers will be able to illustrate their lectures with presentation software, slides or any other media that they could use with a room system. We have tested the ProShare with our VTel MCU and with a PictureTel DVC system. Both performances were flawless. We expect ProShare to multipoint through the MCU with up to five sites. We expect the teachers to find ProShare easy to operate and that once they learn to use it, they will require little support. We expect the students to find the DVC system easier to use than a room system with almost the same quality. We expect DVC to cost one third that of a room system. If these expectations are met, MTSU will deploy many more DVC classrooms through out rural Tennessee.

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