dunbar


 

 
 
 

Computer videodisc education systems 
 

Raden Dunbar 
Executive Officer 

Satellite and Telecommunications Association 
 
Introduction 
 
Discussions about the likely widespread use of videodiscs in systems of 
educational technology have until now tended to focus on the fact that the 
present generation of disc systems are non-erasable. The grooves and pits 
moulded or encoded into the surfaces of, respectively, capacitive and 
optical videodiscs cannot be reconstituted as part of a re-recording 
process. Any alteration of program content or sequence involves creation 
of a new master tape from which a new batch of discs must be 
manufactured. 
 
Educationists normally require an instructional medium which can be 
modified easily and cheaply in the process of regular content evaluations. 
The blackboard, for example, has this sort of flexibility. Thus far, the 
complexity and cost of videodisc reprocessing has been regarded as one of 
the major barriers to its future wide use. 
 
However, the educational potential of videodisc is enormous, even 
revolutionary, as I shall elaborate in this paper. It enables computer 
directed delivery via television screen of alphanumeric, audio, graphic, 
still picture, and moving picture information randomly accessed from very 
large data bases. Depending on the design complexity of video and 
computer programming, this can be done in an almost endless variety of 
sequences and overlays. It combines in the one integrated system 
practically all print and nonprint educational technologies so far devised, 
and provides the foundations for a truly individualised random-branching 
system of interactive instruction. 
 
The development, proliferation and refinement in the United States Japan, 
and Europe of new microelectronic devices for processing information is 
an industrial phenomenon which appears to have no bounds It comes as 
no surprise then to read of the May 1983 announcement by Matsushita 
Electric Industrial Company (O'Brien 1983:17: Williams, N. 1983:6) of a 
major breakthrough in videodisc technology the erasable, reusable 
videodisc for optical disc systems. 



22 Australian Journal of Educational Technology, 1985, 1(1) 

The surface composition of the Matsushita disc can be altered in a 
photochemical process involving crystalline change in a coating tellurium 
oxide/germanium/indium compound when this is exposed to laser light. 
The laser changes this compound from crystalline to non-crystalline or the 
reverse, and alters the degree of crystal reflectivity. 
 
It is widely and confidently predicted that this photochemical disc will 
eventually replace all magnetic, capacitive, optical, and other electronic 
and electromechanical storage devices, and will enable even greater 
convergence of audio, video, and computing technologies. In data 
processing terms, it means the new videodisc will no longer be a read-only 
memory (ROM) device but will provide an expanded read/write memory 
capability. As such, its announcement represents another step towards the 
creation of a powerful and efficient technology-based system of teaching 
and learning which may one day supersede present instructional 
methodologies. 
 
Convergent technologies 
 
Richard Hooper (1982) has observed that convergence of previously 
discrete information and communications technologies is beginning to 
have considerable impact on advanced cultures. He cites the growing 
intermarriage of computing, video, audio, and telecommunications, and 
says that this is contributing to a rapid transition away from the industrial 
era. Marsh (1983:52) suggests that interactive computer-videodisc 
technology is the epitome of convergent technology and symbol of the 
post industrial society: it ushers in "high-tech customisation" of 
information, and may thus enable the "demassification" of society earlier 
predicted by Alvin Toffler (1980). 
 
This paper is concerned with the convergence of video, audio and 
computer technologies into videodisc-based interactive instructional 
systems (or Time-shared, Interactive, Computer-Controlled, Information 
Television - TICCIT- as explained by Butler 1981:17). My objective is to 
examine some of the elements of these systems and my focus will be on 
computer-videodisc hardware and software and on some of the technical 
and organisational problems and procedures relating to courseware 
design and production. Although this orientation excludes detailed 
discussion of the human problems relating to such innovations, I freely 
acknowledge that these must prove to be an issue of overriding 
significance. 
 
On that subject I shall say this: it needs to be remembered that 
convergence of technology is not limited to the physical integration of 
machines. It also involves a rearrangement of the human activity which is 
directly and indirectly linked to them. Even though the development of 
new machines is a complex business it is not nearly as complicated as 
changing the patterns of related human behaviour. The fact is that 
computer-videodisc systems come at a time when Australian educators 
are still trying to adapt to the generation of stand-alone videocassette 
devices introduced a decade age, and when they have just begun to adapt 
to the present generation of computing equipment. 



Dunbar 23 

Another human aspect of hardware convergence has been noted by Bejer 
(1982:78). he observes that the computing and communications equipment 
industries have achieved tremendous growth over the past two decades, 
but have developed, in the most part, unmindful of each other. The 
interfacing of video with computer hardware has largely been developed 
in an incidental way by "cottage" industries outside the mainstream of 
communications and computing. Bejar suggests, however, that this 
separate mating of hardware will be eventually followed by the wholesale 
coalescence of major industrial conglomerates such as IBM and AT&T to 
form a new information industry. 
 
Computer-videocassette systems 
 
As I have mentioned, videocassette technology has been available for a 
decade. At the beginning of the 1970s three-quarter inch U-Matic 
videocassette recorder/players began to appear in schools and colleges, 
and these were followed by a proliferation of videocassette instructional 
software. More recently, lower cost half-inch VHS and Betamax VCRs 
have begun their invasion, especially of primary schools and 
kindergartens previously denied easy access to video technology on 
grounds of cost. 
 
It is true to say that very little video programming played through these 
systems is designed specifically for instructional purpose. Most 
videocassettes used by teachers are off-air recordings of broadcast TV, 
recordings of documentary or feature films, or in Some cases material 
prepared by teachers to illustrate areas of course content. Most commonly, 
video is used in the same way as projected media: it is shown to whole 
classes or groups, and its purpose is entertainment, illustration, or 
enrichment. It is adjunctive to face to face class teaching, and is typically 
regarded as an "audiovisual aid". 
 
It is now possible to drive a videocassette player using microcomputer 
control. This means that CAI programming can be supplemented with 
video segments. In some cases this involves the use of two VDUs - one for 
computer generated information and one for video segments. In systems 
like CAVIS (Copeland 1983ab) a split screen is used to combine both in the 
one display. Various computer videocassette authoring programs are 
available, such as the McGraw-Hill Interactive Authoring System and 
these enable the construction of CAI programs utilising colour 
alphanumerics, graphics, and video segments retrieved by video control 
track indexing. 
 
Computer-videocassette interface provides the means for constructing 
expanded-capability interactive, individualised CAI programs. Due to the 
very large numbers of videocassette players now in Australian schools and 
colleges, and growing microcomputer availability we may see increased 
interest in this type of instructional media. 
 
I suggest that there are some obstacles to this (apart from inherent teacher 
resistance) which are not easily overcome. The design and production of 



24 Australian Journal of Educational Technology, 1985, 1(1) 

programs can be a complex and time-consuming task and it is doubtful if 
sufficient human and other resources can or will be made available for 
experimentation or for building up a sizeable stock of courseware. Most 
cassette programming has not been designed for CAI interaction so that 
appropriate, clean edit points may be difficult to pick. As well, video 
access times in these systems are slow; still frame quality is poor and 
cannot be held for any length of time; and video quality deteriorates with 
dubbing and age. 
 
However, computer-videocassette programming experience by teachers 
and educational technologists must be considered useful as preparation 
for later changeover to computer-videodisc as design and production 
procedures are much the same in both cases. The point is that computer-
videocassette interface is not the same truly Convergent technology as is 
contained in computer-videodisc systems and must be considered only as 
a passing phenomenon. 
 
The development of videodisc 
 
It is appropriate at this point to briefly review the history of videodisc 
development. As Fist (1980 28), Fisher (1982:111) and others have 
recorded, this history goes back to 1927 when John L Baird engraved video 
signals on a gramophone disc in much the same what that audio signals 
were recorded. Baird's hard disc system was not improved on for almost 
forty years and in the meantime an efficient video recording medium was 
found to be the magnetic tape developed by Ampex and announced in 
1956. 
 
It was not until the 1960s that the modern videodisc system was devised 
following intensive developmental work by American and European 
companies including RCA, Philips, Telefunken-Decca, MCA and 
Thomson-CSF. By 1972 all of the videodisc systems currently used had 
been developed and were in place. 
 
It took most of the 1970s for systems promoters to build disc pressing 
facilities, collect marketable titles, and establish marketing networks. In 
1978 Philips/MCA began test marketing of the "Magnavision R" videodisc 
system, and since then there has been a flood of players and discs onto the 
North American, Japanese and European markets. More recently Japanese 
manufactures have entered the competition and the Pioneer VP-1000 
player has become established as a market leader. As was the case with 
videocassettes there are a number of fundamentally different videodisc 
systems on offer and observers are now waiting to see which gains 
predominance. 
 
Classification of videodisc systems 
 
Clement (1981:15) and Onosko (1982:84) classify disc systems by signal 
storage/retrieval method. There are two primary categories, optical 
systems or capacitive systems, each with two sub-categories as follows: 
 



Dunbar 25 

1. Optical systems.  
 
a. Reflective: this system uses an optical-tracking laser-pickup which 

reads the laser light reflected from microscopic pits encoded into the 
disc surface. Examples include Philips/MCA, Magnavox, Pioneer, 
DiscoVision Associates (DVA), and Sony.  

b. Transmissive: an optical-tracking laser-pickup reads the laser light 
transmitted through the disc. The only commercial system of this type 
is manufactured by Thomson-CSF in France. 

 
2. Capacitive systems.  
 
a. Grooved: this system uses a diamond stylus pickup in physical contact 

with grooves moulded into the disc surface. Examples include the 
RCA, Zenith, CBS, and Sanyo systems.  

b. Grooveless: a diamond or sapphire stylus follows electro-tracks 
implanted in the disc surface. Brands include JVC/Matsushita, GE, 
Quasar, EMI, and Panasonic. 

 
In general, optically read discs have a capacity of 54,000 frames per side in 
standard configuration or 108,000 in extended play Individual frames and 
frame sequences can be accessed randomly and played in slow motion, 
freeze frame, frame-by-frame, or fast scan, all without noticeable picture 
distortion. The discs have unlimited life due to a protective resin coating. 
 
Capacitive disc systems have a standard capacity of 108,000 frames per 
side, but only the grooveless system offers random frame accessing and 
multiple play functions. Lifespan varies from 300 play- hours in the case of 
grooved discs to 2,000 play-hours for grooveless. 
 
So far the optical-reflective system has emerged as a market leader and 
with the previously mentioned development by Matsushita of an erasable 
optical-reflective disc the indication are that this system may become the 
industry standard. It is certainly the case that of systems so far reported in 
educational applications the optical-reflective consumer players produced 
by Pioneer (model VP-1000), and educational/industrial players produced 
by DiscoVision Associates, and by Sony (model LDP-1000) are preferred. 
 
Optical-reflective videodisc system characteristics 
 
Each of the 54,000 frames of information in the optical-reflective videodisc 
is contained on a separate spiral track and is addressed with a 1-54,000 
frame number. When the disc is played at the normal speed of 30 frames 
per second two channels of high quality audio are available which can be 
used for stereo music, bilingual audio tracks, or to present commentary at 
two different levels of comprehension. The user can monitor either or both 
audio channels. 
 
Any program segment on the disc can be randomly accessed by the inbuilt 
microprocessor with a search time of between 2 and 10 seconds. This 
means that the program contents can be arranged like a book and 



26 Australian Journal of Educational Technology, 1985, 1(1) 

organised into discrete chapters indexed by a table of contents. For 
educational purposes stand-alone systems can be supported by optional 
index materials such as text or a visual data base built into the program 
sequence. 
 
Both motion sequences and stills can be combined in the programming 
enabling the mixing of different types of media including films, filmstrips, 
videocassettes, and slides. Certain frames can be allocated for 
alphanumeric information and read in freeze-frame. 
 
Without computer interface the system can be utilised for instructional 
purposes. Kemph (1981:648) has reported a number of programs produced 
by the Nebraska Videodisc Design/Production Group which use 
sequences of motion, slow motion and freeze-frame to illustrate actions, or 
which use the indexing/search capabilities for communication of 
encyclopaedic information. The "First National Kidisc" described by Blizek 
(1982) contains considerable educational programming utilising program-
prompted/learner controlled multimotion and freeze-frame, as do 
numerous "how to" discs presently appearing on the US consumer market. 
In the latter case, numerous cookery, handyman, physical exercise, party 
game, and general knowledge discs are beginning to enjoy considerable 
success. 
 
Levels of interactive videodisc systems 
 
Most commonly, interactive videodisc systems are classified according to 
their degree of complexity. This method has been reported by Kemph 
(1981:648), Onosko (1982:91), Daynes (1982b:49-53), and Parcloe (1983:84) 
and comprises three levels of interaction: 
 
Level one: This level comprises stand-alone consumer players such as the 
Pioneer VP-1000, which offer remote control, rapid random access, 
variable quick and slow motion both backwards and forwards, and freeze-
frame. However, no branching or other variable programming facilities 
are included. 
 
Level two: These are educational industrial players which incorporate a 
small programmable microprocessor. Only two such systems are currently 
available in the US - the Discovision models 1,2, and 3, and the Sony LDP-
1000. These players can be programmed on a limited basis to execute a set 
of frame searches and autostops, to wait for input from the user, and to 
branch back into the programmed instructions accordingly. Programs are 
recorded onto the second audio track of the disc and loaded into the 
player's RAM. 
 
Level three: These systems consist of either level one or level two players 
interfaced to a microcomputer. Level three devices are powerful 
interactive instructional systems often involving complex hardware 
interconnections, and considerable courseware production effort. The 
balance of this paper is concerned with such systems. 
 



Dunbar 27 

Computer-videodisc interface 
 
Computer-videodisc interface devices lie at the heart of level three 
videodisc systems. Depending on their complexity they enable 
interconnections between the computer, videodisc player, VDUs, and 
many other peripheral devices. 
 
The problem with the current generation of videodisc players is that 
uniform industry technical standards have not yet been established. This 
means that only some players can be computer-interfaced. It also means 
there is presently no common interface device for all applications. Users 
either fabricate their own interfaces, or purchase purpose-built off-the-
shelf boxes from a small number of US manufacturers. 
 
For example, Aurora Systems Inc. have developed an interface box 
specifically designed to interconnect the Pioneer VP-1000 player with an 
Apple II computer. As detailed by Ahl (1982:56-57), this interface enables 
the computer to duplicate all the videodisc remote controller functions 
(play, stop, freeze, step-forward, step-reverse, shuttle search to address 
indicated, slow forward and backward motion), and as well as sending a 
control signal to the player can also accept the player video signal and 
marry it with the video signal from the computer. However the Aurora 
interface cannot display both video signals simultaneously, and instead 
merely switches back and forth between the two video signals. The 
interface is supplied with a DOS floppy disc which enables the 
incorporator of videodisc player commands into the Apple programs, and 
retails for $US250. 
 
Another box is manufactured by Allen Communications Inc. which 
interfaces the Apple II to the Pioneer VP-1000, system also comes with a 
DOS floppy disc, and retails for $US575 (Onosko 1982:92). 
 
In generously funded experiments conducted by the US Army (reported 
by Ferrier 1982:315) an IBM Personal device custom built by Interactive 
Training Systems Inc. This box (the ITS II) can handle multiple video 
inputs so that more than one disc player can be utilised, and 
accommodates such features as a touch sensitive screen and graphic 
overlay on video. 
 
The US experience has been that videodisc players with a built-in RS-232C 
serial port are most easily computer interfaced, and this presently limits 
the range to the educational/industrial players produced by Discovision 
Associates and Sony. It should also be noted that interface devices 
manufactured in the US are all configured to the 525 line, 60 Hz field, 
NTSC colour TV standard and are thus not useable for PAL (the 
Australian standard) or SECAM configured equipment. 
 
From a British point of view, Parsloe (1983:85) has observed that this 
incompatibility is a real problem. He says that the decision facing many 
potential users of interactive computer-videodisc systems is between 
adapting the master videotape to suit locally available disc hardware, or 
employing universally a system which may not be compatible with local 



28 Australian Journal of Educational Technology, 1985, 1(1) 

standards. The series of videodisc programs produced by AAV-Australia 
Pty Ltd. for GMH (Ogden 1983:20) was developed to NTSC standards and 
necessitates the use of NTSC players and monitors by GMH dealers in 
Australia. 
 
In the future when hardware convergence has been developed to a more 
sophisticated level we can probably expect instructional videodiscs to be 
encoded with all courseware requirements for an instructional sequence, 
including computer programs, alphanumeric information, and video 
sequences. At present these functions are spilt between memory devices in 
the computer, and the videodisc. 
 
A complex computer-video interface 
 
Backer (1982:26-27) has described a complex computer-videodisc 
presentation system developed by the Architecture Machine Group, 
Massachusetts Institute of Technology, which serves as an exemplar of this 
new instructional medium. 
 
The system has three components: 
 
1. Hardware that supplies the imagery and the means for impute, 

comprising a microcomputer, two interfaced videodisc machines, a 
colour graphics processor, a video effects generator, stereo audio 
amplification, and a single colour VDU with touch sensitive screen, all 
interlinked into an integrated system.  

2. Software for the videodisc players and computer that generates the 
graphics for the viewer functions, handles interactions, controls the 
imagery.  

3. The imagery and sound, and the database that represents it. 
 
This arrangement can be considered a sub-system of an elaborate and 
sophisticated supra-system comprising courseware design, production, 
and evaluation processes and learning experiences and outcomes. I will 
later describe some of these aspects in more detail. 
 
In operation, the videodisc players generate video images which are 
mixed by the video effects unit with computer-generated graphics which 
also represent the interactive controls. A touch-sensitive screen mounted 
on the VDU senses input to the screen, and provides the means by which a 
user selects program content. 
 
This screen allows the viewer to interact. The system is interruptable and 
always responsive to the viewer so that sequence changes can occur at any 
point rather than at specific "branching" points. Thus, programs are 
continuously interactive, and are driven by "simultaneous processing" 
from the system, as it dynamically selects the visual and sound material 
based on the viewer's input, and by the viewer, whose interests and 
wishes may change as the program progresses. 
 
The use in this system of a touch-sensitive screen as the exclusive means of 
learner input is an interesting departure. Most Computer-videodisc 



Dunbar 29 

systems use the computer keyboard for input (as is the case with CAI 
programming). Other input techniques reported include light pens, 
paddles, joysticks, voice control (Withrow 1983:26), and sensors implanted 
in models connected to the system (Hon 1982:118). 
 
Integration of courseware design and production 
 
The convergence of computing with videodisc and other peripheral 
hardware for presentation of interactive instructional programming also 
involves the integration of many related courseware design and 
production concepts and functions. 
 
In the Nebraska Videodisc Design/Production Group at the University of 
Nebraska (Dayness 1982a:24) an integrated team approach is used for each 
design/production project involving an instructional designer, at least one 
content specialist, a scriptwriter, an engineer, a computer programmer, 
and a video producer/director. 
 
To produce the American Heart Association computer-videodisc 
cardiopulmonary resuscitation simulator system (Hon 1982:112-120) a 
design/production team was assembled which comprised a television 
scriptwriter (who doubled as the production co-ordinator), two content 
specialists (both cardiac surgeons), two senior Sony videodisc engineers, 
two computer engineers, a video producer/director, a full video 
production crew, two systems designers, a computer programmer, two 
audio engineers, and 65 program evaluators. 
 
A design/production flowchart for computer-videodisc courseware 
published by WICAT Systems Inc. (1982:56-57) details an activity sequence 
integrating needs analysis, instructional design, media selection, script 
writing, artwork, computer programming, formative and summative 
evaluation, talent selection and coaching production planning, 
photography, and video and audio engineering. 
 
The clear evidence is that design/production activity in this sort of 
educational technology is significantly different to that involved with 
lower-level technologies. An unsophisticated tape- slide program can be 
designed and produced quite comfortably by a single teacher possessing 
minimal competence in photography, sound recording, and scrip/writing. 
By contrast, a computer-videodisc program requires input from a team of 
specialists, and this fact must be significant when we consider the future 
use of this technology in educational settings particularly in Australia. 
 
Courseware design 
 
Carefully designed courseware is another key to the successful integration 
of videodisc and computer. The power of the technology is immense, but 
can only be exploited with a highly imaginative and creative approach to 
instructional design, computer programming, and video production. This 
approach is a significant departure from the lineal thinking engendered by 
earlier mediums. Computer-videodisc systems can offer a multiplicity of 



30 Australian Journal of Educational Technology, 1985, 1(1) 

audiovisual parameters in presentational sequences randomly chosen 
according to learner responses. 
 
These parameters include: coloured multimotion pictures. colour still 
pictures; coloured still and moving graphics which can be manipulated by 
the user; displays of alphanumeric information which can be overlayed 
onto picture or graphics backgrounds or displayed in split screen; dual 
audio tracks which can be utilised together or separately with both motion 
or still pictures. a variety of user input methods; and complete random 
accessibility to the database. It is clear that in order to avoid using the 
medium simply as a repository of visual segments, properly designed 
courseware is essential. 
 
Instructional design 
 
Nugent (1980:29), Glenn (1981:61), Blizek (1982:106), Dayness (1982a:24-
25), Kehrberg (1982:98-100) and Copeland (1983b:74-76) have all provided 
numerous examples of computer-videodisc instructional design 
considerations. Some of these are summarised as follows: 
 
1. A preliminary factor is consideration of the particular computer- 

videodisc system the program will be designed for. Because options 
presently vary from system to system the designer cannot ignore the 
impositions of hardware configuration.  

2. It is necessary to choose the most appropriate symbol or code (pictures, 
print, and/or audio) for each unit of instruction, and to decide if 
picture motion is required (and if so, what sort). With videodisc the 
designer has an unprecedented opportunity to match the information 
to be presented with the optimal code.  

3. A decision should be made as to whether and when interaction is 
appropriate, as this will influence the linearity or nonlinearity of 
programming.  

4. The appropriate locus of control should be selected. This can lie either 
with the computer, the learner, or a combination of both. If control rests 
solely with the computer, the learner may be given little opportunity to 
select individualised strategies most appropriate to personal learning 
styles.  

5. Programming needs to be stimulating and "human", rather than 
appearing to come from a cold, sophisticated information system. One 
aspect of this is that sequences need to have a high repeatability value.  

6. The Nebraska group (Daynes 1982a 24-25) has defined seven sets of 
videodisc frames: orientation information, content, decision, comment, 
summary, problem, and "help". Each category of information has a 
specific function in an instructional sequence 

 
There are many more examples available. The important point emerging 
from the literature is that instructional designers using this medium need 
to be aware of its unique possibilities, the technical limitations of systems, 
and the various options open to computer programmers and video 
producers working on the design/production team. 
 



Dunbar 31 

Computer programming 
 
Bejar (1982:88-100), Daynes (1982b: 58-59), Lubar (1982:62-70), and Hon 
(1982:120-132) have all reported various underlying programming 
considerations. 
 
With regard to the creation of visual displays, Bejar stresses the need for 
control structures in programming which support "electronic 
visualisation". Citing DeFanti (1980:90) he argues that existing computer 
languages do not contain control structures capable of creating and 
manipulating electronic images in real time. Likewise the software support 
for videodiscs in education often lacks the capability for overlaying video 
and for permitting responses on the part of the student other than 
choosing from a given set of alternatives. 
 
Bejar also notes the recurring problem of program portability. He says that 
because, inevitably, different schools will have different software 
development costs are growing, developers should create software that 
can be run on a number of different systems, thus making it fully 
transportable. 
 
With regard to learner interaction, Hon has shown that a difficult 
programming task can be the creation of algorithms which accurately 
assess the value of multiple learner responses. In order to assess learner 
performance takes too little or too much time, and whether each part of 
the performance occurs in the proper sequence. Based on this evaluation, 
the software then displays the appropriate graphics and video 
demonstrations and explanations of how to improve performance. This 
can lead to the creation of complex program control structures. 
 
These are only three examples of the programming idiosyncrasies in 
computer-videodisc system. To a certain extent they can be managed by 
teachers using authoring systems such as Apple SuperPilot (Kellner 
1982:104-105) which enable generation of high resolution colour text and 
graphics, as well as incorporating a set of videodisc control commands. 
However, complete mastery of videodisc-computer systems requires 
sophisticated programming skills. There are clear implications in that for 
educators if the technology is to succeed in educational settings. 
 
Video production 
 
Blizek (1982:108-110), Dayness (1982a:25-26), and Wright (1982:18,112) 
have described in great detail the sorts of video production possibilities, 
strategies, and problems presented by computer-videodisc systems. Some 
of these are: 
 
1. The pace of video programming can be varied according to content 

demands and as a means of stimulating user attention. Certain kinds of 
information such as rule statements, examples, and problem solving 
sequences can be added as a series of still frames and segments can be 
repeated. This serves to slow pacing whereas motion sequences played 
at normal speed or faster can achieve different responses.  



32 Australian Journal of Educational Technology, 1985, 1(1) 

2. Programs can be organised like a book, with a table of contents and a 
series of chapter like segments. Others may follow the conventional 
pattern of beginning, middle, and end. Some may be organised into a 
series of discrete tracks with the actual sequence being determined by 
user responses.  

3. The style of video programming can be very direct and personal. The 
narrative or dialogue can communicate directly to the user, and elicit 
direct responses. An open ended approach can allow the user to 
provide conclusions or choose amongst alternatives.  

4. Content can be broken down into a series of short segments with no 
transitions linking them, or with transactions that allow segments to be 
used in various combinations. Some video segments containing 
references or optional materials may never be seen by anyone. 

 
As with other elements in computer-videodisc production, video 
producers need to be cognisant of the technical limitations of likely player 
systems, and of the new problems and possibilities presented by 
computer-controlled access to video segments. This means they need to 
work closely with instructional designers and computer programmers, 
and need to be in possession themselves of some of those skills. 
 
Costs of computer-videodisc educational technology 
 
Because of the newness of the technology and the volatility of the market it 
is too early for an accurate or comprehensive determination of cost to be 
made. So far, commentators in the US have been very wary of making firm 
predictions. In the Australian setting it is impossible even to envisage 
vaguely what likely costs will be. 
 
However, certain generalisations can be made. Although dependent on a 
number of factors, educational users of the medium can expect that 
outlays on presentation hardware and finished discs will pale into 
insignificance when compared with program development costs. When 
we consider the financial implications of the sorts of production efforts I 
have so far outlined it is clear that major cost-benefit issues arise. These 
will only be satisfactorily resolved when economies of scale are 
introduced. That is turn means each instructional program will need to be 
distributed very widely to reduced unit costs. 
 
At present in the US, the hardware components of typical computer- 
videodisc presentation systems can be assembled for between $US3000 
and $US5000. Those costs are bound to reduce in line with all other 
information technologies. We can safely predict that the day will come 
when the price of such systems will be of the same order as today's lower-
level educational technologies. 
 
Individual discs are being pressed in US, Japanese, and European plants 
for between $US10.00 and $US20.00 a copy depending on production run 
quantities (Fisher 1982:111-112), plus setting up costs of around $US2,000 
per run. Butler (1981:17) has calculated that on these figures videodisc 
duplicating costs outstrip videocassettes unless large production runs are 
ordered. This high duplication cost is caused by the present non-



Dunbar 33 

erasability of videodiscs by users. Perhaps when the erasable disc 
penetrates the market single-unit duplication costs will decrease. 
 
However, the costs of program production can be enormous. Butler quotes 
between $US500,000 and $US700,000 for sufficient videodisc courseware 
for a one-year college course. He says videodisc producers report one-
hour consumer discs cost $US100,000 to develop, with breakeven point 
reached when 2,000 discs are sold. It is clear that if educators wish to 
utilise the technology they will need to be in a position to share 
developmental costs, and Butler suggests the formation of educational 
consortiums to achieve this. 
 
It should be pointed out that disparity between hardware and courseware 
costs is no different to any other form of instructional media. For example, 
the costs of producing an effective slide-tape sequence are considerably 
higher than the cost of one presentation unit. However it is true to say that 
new financing arrangements implicit in the introduction of computer-
videodisc technology will not begin to pervade US schools until the 
middle to late 1980s. That probably means we can expect its appearance in 
Australian schools Sometime during the 1990s. 
 
Educational research 
 
So far very little computer-videodisc research has been reported. In the 
literature survey which preceded compilation of this paper only two 
research reports were located. 
 
One (Andriessen and others 1980) comprised a simple experiment 
conducted at the Philips Research Laboratories to observe learner 
reactions in a computer-videodisc instruction environment. It was largely 
designed to provide data for improving system hardware layout and 
courseware sequencing. Apart from developing a quantity of technical 
material the study also collected impressionistic data from participants. In 
general, subjects expressed positive opinions about their experiences with 
the medium. 
 
The second (Boen 1983) was a comparative study in which two groups of 
subjects were taught an identical instructional sequence, one by computer-
videodisc, and the other by traditional lecture method. The results were 
subjected to statistical tests of comparison and it was concluded that the 
group receiving instructional from computer- videodisc passed the final 
tests with a significantly higher score than the traditional group. 
 
However, as Butler (1981:17) says, considerably more research is needed 
into the medium to establish the precise nature of its educational efficiency 
and effectiveness, and to determine administrative savings in learning 
time, classroom space, and staffing, as well as appropriate methods for the 
preparation of educational organisations for its inevitable wider use. 
 
 



34 Australian Journal of Educational Technology, 1985, 1(1) 

Conclusion 
 
My concern in this paper has been with the convergence of video, audio, 
and computing technologies into videodisc based interactive instructional 
systems. My objective has been to examine some of the elements of these 
systems, particularly hardware configurations and courseware design and 
production procedures. 
 
From readings of the steadily increasing quantity of literature about 
computer-videodisc systems beginning to flow from US and British 
sources I have identified four basic issues: 
 
• The computing equipment, videodisc players, videodisc production 

facilities, and computer-videodisc interface devices have been 
developed and in some instances are now in the process of refinement. 
At present, this hardware is only freely available in the US, Japan, and 
Europe. There are a number of portability/compatibility hardware 
issues which need to be resolved.  

• Some institutions and corporations are actively engaged in educational 
courseware experimentation and development. In the US these include 
the University of Nebraska, University of Utah, University of 
Minnesota, University of Florida, and the Massachusetts Institute of 
Technology. The United States armed forces are conducting generously 
funded trials of the technology as tools for military training. 
Predictions about future use tend to be optimistic.  

• The technology comes in the form of integrated systems which involve 
interrelationships, interactions, and interdependencies between new 
machine and new human processes. These systems are significantly 
different to traditional education systems.  

• There are many unresolved aspects of the technology, including costs, 
reliability, and educational efficiency and effectiveness. These issues 
may be settled with the passage of time, and in the course of further 
research. 

 
It remains to be seen how computer-videodisc educational technology will 
be received by educators trained in traditional educational methodologies. 
It cannot be considered an "audiovisual aid" which will be easily absorbed 
into traditional classrooms. Rather, it is better seen as an alternative to 
traditional methods, and therein probably lies the seeds of a major 
educational controversy. 
 
Annotated bibliography 
 
Ahl, D.H. (1982). "Aurora Systems Videodisc Controller", Creative Computing, 8, 1, 

56-57. 
Describes a low cost ($US250) videodisc interface manufactured by Aurora Systems Inc. 
which links the Pioneer VP-1000 Videodisc Player to an Apple II microcomputer. 

Andriessen J.J. and Kroon, D.J. (1980). "Individualised Learning by Videodisc", 
Educational Technology XX, 3, 21-25.  
Describes an experiment conducted at Philips Research Laboratories, Geldorp, The 
Netherlands, using a Philips VLP videodisc player driven by a Philips P857 
minicomputer. A short instructional course was prepared and presented using the 
system and learner opinions and reactions were collected. 



Dunbar 35 

Backer, D. (1982). One-of-a-Kind Video Programs. Instructional Innovator 23, 2, 26-28. 
Describes experimental interactive video/computer instructional systems built by the 
Architecture Machine Group at Massachusetts Institute of Technology. System Comprises 
a microcomputer interlinked to two videodisc players, a colour graphics processor, video 
effects generator, and a monitor with touch sensitive screen. Outlines operation of system, 
instructional design technique used, and disc production method. 

Bejar, I.I. (1982). "Videodiscs in Education: Integrating the Computer and 
Communication Technologies". Byte, 7, 6, 78-104.  
Very detailed article discussing educational implications of interactive videodisc 
technology based on recent trails performed at the Educational Testing Service, 
Princeton, NJ. Reviews hardware considerations and options (videodisc players and 
microcomputers); technical and software interface problems; software issues; 
programming style; courseware peculiarities. 

Blizek, J. (1982). "The First National Kidisc - TV Becomes a Plaything". Creative 
Computing, 8, 1, 106-110.  
Outlines program design and production techniques utilised in development of US 
children's entertainment/instructional videodisc interactively controlled by 
microprocessor built into the Laservision videodisc player. Emphasises innovation 
methods necessary to utilise full capacity of system. 

Boen, L.L. (1983). "Educational Technology Research: Teaching with an Interactive 
Video-Computer System". Educational Technology XXIII, 3, 42-43.  
Brief description of a study which compared Computer Directed Instruction (CDI) 
utilising a video-computer system with traditional lecture method. Results were 
subjected to a statistical test of comparison which showed students instructed by CDI 
scored Significantly higher than those taught by traditional method. 

Butler, D. (1981). "5 Caveats for videodiscs in Training". Instructional Innovator, 26, 
2, 16-18.  
Appraisal of videodisc instructional systems which highlights their technical limitations, 
difficulties of mass producing quality instructional software, costs of software 
development, and certain other obstacles. Concludes that potential of medium far 
outweighs obstacles. 

Clement, F. (1981). "Oh Dad, Poor Dad, Mom's Bought the Wrong Videodisc and 
I'm Feelin' So Sad". Instructional Innovator, 26, 2, 12-15.  
General description of videodisc characteristics and potential. Emphasises differences 
between various systems, especially between lineal and random-access units, and 
compares four player systems - reflective optical, transmissive optical, grooved 
capacitance, and grooveless capacitance. 

Copeland, P. (1983a). "An Interactive video System for Educational and Training". 
British Journal of Educational Technology, 14, 1, 59-65.  
Description of the development and testing of a British video/computer interactive 
instructional system called CAVIS. System utilises a microcomputer-driven VHS 
videocassette recorder/ player. utilises computer generated alphanumerics and VHS 
video segments in various random combinations. 

Copeland,P. (1983b). "CAVIS - From Concept to System". Media in Education and 
Development, 16, 4, 74-79.  
More comprehensive and recent version of previous article by the same author. Includes 
reference to use of videodisc in an interactive video system, and more detailed treatment 
of courseware production methodology. 

Daynes, R. (1982a). "Experimenting with Videodisc". Instructional Innovator 27, 2, 
24-44.  
Outlines techniques used at Nebraska Videodisc Design/Production Group, University 
of Nebraska, to produce instructional videodisc/computer programs. Describes 
production sequence from design to premastering tape stage, and highlights differences 
of pace, organisation, and style inherent in CDI/videodisc programs. 

Daynes, R. (1982b). "The Videodisc Interfacing Primer". Byte, 7, 6, 48-59.  
Comprehensive and well illustrated description of videodisc systems, CDI/videodisc 
programming techniques, and production methods utilised at Nebraska Videodisc 
Design/Production Group. Includes a glossary of videodisc interfacing terminology. 

 
 
 



36 Australian Journal of Educational Technology, 1985, 1(1) 

DeChenne, J.A. and Evans R. (1982). "Simulating Medical Emergencies". 
Instructional Innovator, 27, 1, 23.  
Describes a CDI/videodisc system used to simulate medical emergencies and used in the 
training of medical emergency specialists. Software is an involved branching program 
interlinked to videodisc. Includes full sound effects of injured patients. 

DeFanti, T. (1980). "Language Control Structures for Easy Electronic Visualisation". 
Byte, 5, 11, 90. Cited by Bejar, I. (see above) 

Ferrier, S.W. (1982). "Computer-Aided Interactive Video Instruction: Closing the 
Gap Between Needs and Outcomes in Competency-Based Leadership, 
Management, and Organisational Development Training". Programmed Learning 
and Educational Technology 19, 4, 311-316.  
Detailed account of a CDI/videodisc project implemented at the US Army Organisational 
Effectiveness Centre and School, Fort Ord, California. Outlines nature of OE skills 
required of Army officers and difficulties of achieving instructional results using 
traditional lecture methods (needs analysis). Describes CDI/ videodisc system developed 
by Interactive Training Systems, and results of implementation of that system. Concludes 
that method is a valid, efficient, and cost-effective adjunct method of training suitable 
leadership, management, and OE behaviours. 

Fisher, D. (ed.) (1982) "Videodisc Status Report". Screen Digest, June.  
Comprehensive analysis of videodisc technology and state of the international videodisc 
developments and market. Lists world hardware manufacturing facilities (including 
statistics on output) and manufacturers of programming and courseware. Includes 
details of pressing costs, and a review of overall prospects. Concludes that videodisc will 
be a potent force for change in information industry. 

Fist, S. (1980). Videodisc: Coming Ready or Not. Australian Video Review, 1, 1, 28-30.  
General outline of videodisc technology, system types and potential applications. 
Includes very detailed descriptions of electronics involved. 

Fist, S. (1981). "The Logical Case for Videodisc". Australian Video Review, 1, 5, 18-19.  
Overviews development of videodisc. Compares videodisc with videocassette. 
Speculates on future competition to videodisc from bubble memory systems and 
holography. 

Glenn, A.D. and Kehrberg, K.T. (1981). "The Intelligent Videodisc: An Instructional 
Tool for the Classroom". Educational Technology XXI, 10, 60-63.  
Description of the development, testing, and application of an interactive CDI/videodisc 
instructional system prepared by the Minnesota Educational Computing Consortium, St. 
Paul, Minnesota. System utilises an Apple II interfaced with a Pioneer VP-1000 videodisc 
player, and software for a five-unit course in economics. Outlines education! advantages 
of the interface, and identifies certain key issues for users and developers of similar 
systems including organisation for courseware development, costs, hardware selection, 
and training of educators. 

Harris, J. (ed.) (1982). "Bell and Howell Self Writing Training Software". Australian 
Video Review, 2, 5, 22.  
Brief description of the Bell and Howell Professional Authoring Software System (PASS) 
run on a 48K Apple II driving either a VHS or Beta videocassette recorder/player or the 
Pioneer Discovision Videodisc player. 

Hon, D. (1982). "Interactive Training in cardiopulmonary Resuscitation". Byte, 7, 6, 
108-138.  
Extremely thorough description of the development, testing, and implementation of an 
interactive instructional program for training medical emergency workers in correct 
technique of CPR. system is based on CDI/videodisc hardware linked to electronic 
manikins. Courseware provides instruction, prompts, questions, performance monitoring 
and assessment. 

Hooper, R. (1982). "Keynote Address to the May 1982 ASET Conference on The 
Use of Telecommunications in Education and Training." Australian Society of 
Educational Technology, Sydney, (audiocassette). 

Jarrett, G. (1983). "Philips Ties its Interactive Future to Teletext". Audiovisual, 133, 45. 
Report of an interview with Paul Bradley of Philips Industries regarding future 
developments by Philips of interactive CDI/video technologies. Claimed that despite 
advantages of videodisc, non- erasable recorded technologies must be replaced with 
systems which allow rapid information update and alteration. Cites teletext technologies 
as a possible option. 



Dunbar 37 

Kehrberg, K.T. and Pollack R.A. (1982). "Videodiscs in the Classroom: An 
Interactive Economics Course". Creative Computing, 8, 1, 98-102.  
Description of the Minnesota Educational Computing CDI/video interactive economics 
course including student interactions, the development process, production and post-
production, costs, and future potential. 

Kellner, C. (1982). "V is for videodisc". Creative Computing, 8, 1, 104-105.  
General description of the Apple II/Pioneer VP-1000 interactive system written by an 
Apple Computer Inc. courseware developer. Includes brief description of some 
programming features using Apple SuperPilot, an instructional authoring language. 

Kemph, J. (1981). "Videodisc Comes to School". Educational Leadership, 38, 8, 647-649.  
General overview of entire educational CDI/videodisc field written by a producer-
director at Nebraska ETV. Describes system capabilities and levels of interaction. Outlines 
two pilot programs: "Basic Tumbling Skills" and "Mejore Su Pronuncacion" produced by 
Nebraska Videodisc Design/Production Group. Says that medium is hampered by 
shortage of good quality software. 

Kozen, N. (1983). "videodisc Bibliography". Educational Technology XXIII, 2, 52-53.  
Bibliography of US CDI/videodisc literature including 25 journal articles and two books. 

Lubar, D. (1982). "Adventures in videoland". Creative Computing, 8, 1, 60-70.  
Very detailed description of design and programming method for production of a 
microcomputer/videodisc interactive game called "Rollercoaster", including a full 
program listing (BASIC). 

Marsh, P.O. (1983). "Ed Tech Professional Literature Reviews: Videodisc/ 
Microcomputer Courseware Design". Educational Technology XXIII, 3, 51-52.  
Detailed review of DeBloois M.L. (ed.), Videodisc/Microcomputer Courseware Design, 
Educational Technology Publications, New Jersey. Describes content of book, and general 
system characteristics of interactive videodisc. Identifies 6 major issues related to 
implementation of CDI/videodisc. 

NUGENT G.C. and Stone C.G. (1980). "Videodisc Instructional Design". Educational 
Technology XX, 5, 29-32.  
Article written by a designer and a scriptwriter with Media Development Project for the 
Hearing Impaired, University of Nebraska States that CDI/videodisc courseware design 
follows same sequence as any media product but that certain new procedural elements 
are introduced: consideration of the CDI/videodisc system to be used; selection of best 
combination of symbols and codes; selection of interactivity; selection of control locus - 
learner or computer? Describes a selection of authoring strategies. 

O'Brien, R. (1983). Erasable Discs May Oust VTRs. The Australian, Monday 30 May.  
News item from Tokyo correspondent reporting the development by Matsushita of the 
erasable videodisc. Instead of using pitted disc, erasable discs have a coating of 
germanium and indium on tellurium oxide. Laser shots change this compound from 
crystalline to non- crystalline and vice-versa. Article also mentions similar development 
by Sharp. 

Ogden, J. (ed.) (1983). "Interactive video". Arts and Education, May, 20.  
Question-and-answer promotional article describing interactive videodisc programs 
prepared by AAV-Australia. 

Onosko, T. (1982) "Vision of the Future". Creative Computing 8, 1, 84-94.  
Comprehensive overview of videodisc to microcomputer interface technology which 
describes, compares and classifies systems; discusses characteristics; and details certain 
entertainment and instructional applications. Concludes with a number of predictions, 
including mention of bubble memories. 

Parsloe, E. (1983). Interactive Video. Media in Education and Development, 17,6, 83-86. 
Overview of entire interactive video/microcomputer field by UK writer. Details hardware 
and software problems and prospects. Concludes that technology presages a major 
revolution in education and training. 

Thomas, W. (1981). "Interactive Video". Instructional Innovator, 26, 1, 19-44.  
General review of interactive video including teletext, videodisc, and computer 
interfaced videodisc and discusses prospects. 

Thorne, K.G. (1979), ''The Teledec Video Disc". Audio Visual Australia 2, 1, 6-8.  
Early review of principles of videodisc technology. Includes statistics data showing 
decreasing software and hardware costs of Videodisc and videocassette compared with 
project media. Describes a capacitance videodisc system called the Teledec video disc 
(now outmoded). 



38 Australian Journal of Educational Technology, 1985, 1(1) 

Toffler, A. (1980). The Third Wave. New York: Morrow. 
Walker, J. (ed.) (1981). "What's New in Video?". Instructional Innovator, 26, 2, 8-11.  

Describes a number of new developments in video hardware, including interactive 
computer driven videodisc and videocassette systems. Details some obstacles to these 
innovations, and mentions cost/benefit considerations. Concludes that new technologies 
will benefit education. 

White, B. (1982). How to prepare for videodisc. Instructional Innovator, 27, 11, 17-18.  
Brief introduction to instructional videodisc which emphasises importance of learning 
correct techniques for evaluating videodisc courseware. Notes that videodisc is a potent 
instructional medium which could be easily abused or misused, thus lessening instructor 
credibility. 

WICAT Systems Inc. (1982). "Interactive Videodisc Design and Production. Byte, 
7(6), 56-57.  
Illustrated flowchart detailing design and production schedule for interactive 
videodisc/microcomputer courseware development. 

Williams, D.V. and Gayeski, D.M. (1983). "Interactive Assessment". Instructional 
Innovator 28, 2, 21-22.  
Discusses usefulness of interactive computer/video systems for providing immediate 
assessment feedback on learner performance, as well as a range of other activities, 
preferences, and attitudes. Says that technology based interactive assessments provide 
greater learner motivation, increased "face validity', shorter testing time, better test 
scheduling, improved test security, and improved timing and pacing. 

Williams, N. (ed.) (1983). "New Laser Disc Can Record and Play Back". Electronics 
Australia, 45(7), 6.  
Description of the Matsushita germanium/indium/tellurium oxide erasable videodisc. 
Includes diagram. 

Withrow, F.B. and Roberts, L.G. (1983). "Video with Razzle Dazzle". Instructional 
Innovator, 23, 3, 24-26.  
Detailed overview of convergence of TV, video, microcomputing, and 
telecommunications. of particular interest is description of developments in interactive 
TV and video, and random access video using voice activated interaction. Ends with 
optimistic description of future of educational technologies. 

Wright, V.O. (1982). "How to Format Slides for videodisc". Instructional Innovator, 
27, 11, 18-112.  
"How to" article which describes procedure for preparing photographic slides for 
videodisc mastering. Includes specifications for aspect ratio, safe image area, slide 
exposure, multiple stills, and simulated motion. 

 
Please cite as: Dunbar, R. (1985). Computer videodisc education systems. 
Australian Journal of Educational Technology, 1(1), 21-38. 
http://www.ascilite.org.au/ajet/ajet1/dunbar.html