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The implications of laser optical disc formats in formal and distance education: Pictures, text and audio from silver discs

Dick Fletcher
Managing Director New Media, London, UK

Evolution not revolution

Over 500 years ago, first Laurens Coster in Holland, then Johannes Gutenberg in Germany and William Caxton in England unveiled printing presses on a world that was largely unprepared for them. There were no retail outlets for books, there was no distribution system, the market potential was minute - purchasers had to be both rich and literate. One of technology's most important challenges to human endeavour did not transform anything overnight. Monks were not suddenly put out of work. Vellum supplies did not dry up. And people did not immediately set up ten year training courses to teach their children to decode and encode text.

Things are pretty much the same today with the new information technologies. Over the past twenty-five years there has been a succession of new technologies set to transform the way people are taught - programmed learning texts, film strips, multimedia packs, computer programs, videotape, and interactive video. None of them has revolutionised our lives overnight.

The fear of teachers and trainers that somehow they would be done out of a job by the next generation of machinery is an ever present paranoia that has proved to be completely unjustified. There are more teachers and trainers than ever; more money than ever is being spent on education and training; and there are ever more courses and programmes. Education for life is no longer a novel concept.

None of the new technologies has been an out-and-out failure either. Most people would agree that over the last twenty-five years education and training have indeed been transformed and that the resulting improvement in quality has been greatly assisted by each turn of the technological wheel.

The announcement, expected in 1989, of the launch of Compact Disc-Interactive - pictures, text, sound and data all on one fully interactive compact disc - should not create alarm and consternation. The wheel is taking another turn. The arrival of a new technology can be welcomed as providing another resource to a hard-pressed and hard-working profession. The next generation of technology will cause us all to adapt our educational and training practices, but will not overthrow the old order for the new. Evolution is the key, not revolution.

Many of the changes that have come about in the last twenty-five years have one way or another involved developing techniques and experience in interactivity. Programmed learning texts provided an early and useful start along the path. Computer Based Training enabled us to dispense with page numbers and cards and put all the material into the digital domain.

Linearity with Interactive Laser Vision

Interactive Laser Vision in this context has been equally successful. It has given us high quality video images and stereo sound. However, because it is in analogue form, it has meant that - however ingenious designers may be - interactive Laser Vision programme materials have had to be linear: the designer has decided that a student will travel from A to Z and carry out certain tasks along the way. Some materials have appeared to offer choice in the route by providing branches and loops. Yet the fact of the matter is that these branches and loops have only served to provide short forays off the main track for those who could not grasp the principles first time round. And the quantity and direction of different branches and loops has been severely curtailed by the limited capacity of the disc.

This linearity may be fine for a lot of industrial training needs - for example, those that deal with cut and dried procedures. However, it is less satisfactory for dealing with varying levels of entry behaviour and knowledge, and with topics that may be concerned with attitude or that may have a variety of equally acceptable outcomes.

Improved interactivity with Compact Disc-Interactive

With the next generation of interactive players, Compact Disc-Interactive (CD-I), the biggest benefit comes from the quality and quantity of interactivity that it offers. Whereas with Laser Vision, it is the designer who decides what will be seen on the screen at any time, CD-I allows the user more choice about what to see and hear. A programme can be stopped at any moment and the user can journey around the audiovisual database at will in different styles - hunting for information, grazing through to pick up all the detail needed, or just browsing to get an overall picture. Instead of being confined to a relatively small number of options which must be taken step by step, CD-I users will be offered a myriad of opportunities in a style to suit their needs.

For example, CD-I is an excellent medium for audiovisual databases. In the Grolier multimedia encyclopedia which my company is currently producing, a linear audiovisual presentation on the subject of Science and Technology may be interrupted at any moment. The caption of a picture depicting Chinese astrology may be called up; several key words in that caption are highlighted to denote that there are references on the topic in the 10 million word text database; this is then searched for a relevant reference; a list of all references is offered and a particular entry chosen; in reading that entry an icon is observed in the top right hand corner of the screen associating the reference with a map; that map may show the development of routes between Europe and China, including the activities of Alexander the Great and Marco Polo; this in turn can lead you on into the Time Machine, an illustrated view of world history during whichever century and from whichever geographical perspective you may choose.

And that is not all. Young children can learn picture, shape and word recognition with a virtually endless succession of activities. And the CD-I disc can be programmed to match the challenges to the child's interests and ability. In learning a foreign language like Japanese, the student may choose to visit a shop, point to an object using a pointing device such as an infra red control, hear and/or read the correct way of asking for it, before engaging in a dialogue to order it. Using the same material a learner may click on an object and both see and hear the Japanese word for it. Print outs of the chosen dialogue may be obtained. Instant translation in any of 15 different languages can then be called up by the beginner or the insecure.

The extra flexibility of a CD-I disc and the greater freedom provided to the user will enable the educator to devise richer and deeper material.

Cost savings with CD-I

Then there is the question of cost. Interactive Laser Vision equipment can do some of the activities described above. But it is expensive - AU$10,000 or more for all that is needed:
Even then, when you have connected all the bits together, it is non-standard. You need a videodisc made to run on the television system your country uses, and a number of floppy discs. At present there is a wide variety of computer control software programs for interactive Laser Vision. It is therefore likely that you will only be able to use a limited range of programmes.

The arrival in early 1989 of CD-I (Compact Disc-Interactive) should help change all that. It will provide text, audio, graphics, video and control data all on one compact disc. A disc bought anywhere in the world will play on your player with your television set. The CD- I player is a very powerful computer that, like the CD-Audio player, does not need all the paraphernalia of computer systems. For the first time those wanting to use interactive multimedia training materials will need only:

Production prototype CD-I players are now (September/October 1988) being delivered to developers from Japan. Deliveries in quantity are scheduled to start in early 1989 with the launch of a consumer version promised for late 1989, early 1990.

International standards with CD-I

A CD-I player is just one box that can be carried under the arm. Instead of the plethora of wires needed to connect up interactive Laser Vision devices, there can be just two wires coming out of the back of a CD-I player: one for the mains electricity and the other to plug into your television set. Of course, if you want floppy disc drives, printers and modems, you can have them too - a CD-I player is just a powerful computer with a clever operating system.

Buy a disc anywhere in the world and play it on your machine. Play programmes without reference to a user's manual. Pull a bit of audio from over there, match it with a picture from here, and overlay whichever bit of text you like. And you can play all your CD audio discs on it as well. And you will not pay over the odds - latest forecasts have the player priced at under AU$2,000. With a potential world market in prospect, indications are that discs to be played at home will cost from just AU$19.95 to AU$199.95.

Fantasy? No. Many consumer programmes and some educational materials are now in production - for example, New Media is producing the Grolier Multimedia Encyclopedia; other companies around the world are at work on such diverse titles as Time-Life natural history guides, Nancy Sinatra's biography of Frank, guides to everything in Sport, the Bodydisc, and guided tours of the Smithsonian Institute.

The digital storage capacity of CD-I

Compact Disc-Interactive is an all-digital system which will deliver pictures, sound and text to existing analogue television receivers - regardless of whether they are PAL, NTSC or SECAM. Up to 650 Megabytes of data can be stored on one disc and played back in real time. This means that just over one hour of moving video or cartoon animation can be stored on a single compact disc; or more than 7,000 separate photographs; or just over one hour of audio in up to 16 different languages (or over 17 hours of audio in one language); or 100,000 pages of text. Or whatever combination of these suits your purpose. The space on the disc taken by each is determined by the designer.

Because the system is operating in real time and the transfer rate is limited, the moving video is confined to about 50% of the screen area - so, on a 16 inch television set, instead of having a picture 12 inches by 9 inches, the moving video picture will be slightly bigger than 8 inches by 6 inches. Of course if you must have full screen motion video, you can. You can combine the multiple plane facilities of CD-I with chrome key overlays to achieve it.

How is all this accomplished? The player incorporates a powerful 32 bit processor. Four different planes are available on the screen at any one time - a front plane for a cursor, two video planes and a background plane. The video planes can be interchanged in a variety of ways to simulate most standard video effects - a dissolve from one to another or a cut or several different kinds of wipe; part of a picture can be made transparent to see a segment from another behind it. You can even feed a videotape from an external source onto the back plane if you wish.

By having up to 16 different audio channels, different quality levels of sound can be presented to the listener. Use everything and you have just over one hour of the wonderful quality sound of CD-Audio that we know already; use eight of the 16 channels and have two hours of good quality stereo - in fact so good that most listeners will not be able to tell the difference. If the sound is being played back through a mono television set, then lose the stereo and have four hours of high quality audio. If you use only one channel, then seventeen hours of perfectly clear narration or acceptable background music are available - genuine interactive audio for those who are looking for it, as well as perhaps a talking book for the blind.

Other compact disc technologies

Life is never straightforward. And the world of multimedia is predictably complicated by the development of a number of rival systems. Apple's HyperCard is just the start of many exciting products for the new Macs. There is another digital multimedia system coming down the track as well. CD-I has been described in detail because the technology is available here and now it is possible to plan the production of material to known delivery dates. DVI (Digital Video Interactive) was announced in 1987, but there's no known date when players will roll off the production line. Furthermore the Labs say you'll still need an IBM AT or 386-based computer to run it when it does arrive, so prices for the system are being quoted in thousands of pounds, not hundreds.

There are also hybrid analogue and digital players of course. CVD (Compact Video Disc) is being developed in California and Philips/Sony have already launched CD-V (Compact DiscVideo). But neither of these offers the combination of technical features, worldwide standardisation, early delivery and low price that is a feature of Philips/Sony backed CD-I.

The implications for formal and distance education

It often seems that the easiest thing in the world is to identify a new educational method or technology and label it as the most significant, the most far-reaching, the most revolutionary, and so on. In earlier days, when I worked in broadcasting and curriculum development in Pakistan, Malaysia, Southern and East Africa, I participated in advocating the wonders of audio tape recorders, television and radio programmes, and even structured reading cards. They have all helped, but identifying changes in educational approach is a bit like clicking your fingers to keep elephants away. Since we are all doing it, we have no way of measuring in any scientific way how effective it is.

The potential for creating teaching materials that are rich and deep has always been great. That is because education is such an exciting and challenging profession. The new optical electronic technologies with their capacity to store and play back massive amounts of material offer new horizons. But there are obstacles. Cost is one. CD-I is an improvement on Laser Vision - the equipment is potentially cheap enough to see a growing installed base of players in the next few years - AU$2,000 should come tumbling down over three years if the pricing pattern of CD-Audio is followed. The cost of producing discs is high - about the budget of a 'B' movie, say from AU$500,000 up. On the other hand, with potential audiences around the world in millions, that should not be a problem.

Another obstacle is educational practice. The fact of the matter is that interactive learning materials by their very nature are best suited to a one-to-one relationship. That is not to say they cannot be used in group and classroom situations. Our own Bodydisc and Living Arctic discs are used in this way in British classrooms. But access to large audiovisual databases and a lot of interactive materials will require changes in educational practice and style. Maybe education will become more efficient, with school pupils working alone (perhaps at home) when acquiring information, and only participating in school or group activities with their peers when learning to apply that information.

Maybe then teachers really will be free to educate - to use their skills to bring out and develop whatever talents and aptitudes their pupils have been born with. But this person is now old enough to know that this way of talking is evolutionary, not revolutionary.

NB: The prices quoted in Australian dollars are approximate and are based on UK and USA prices converted at the current (August 1988) rates of exchange.

Author: Dick Fletcher speaks and writes internationally on interactive technologies. He is Managing Director of New Media, a company based in London UK which designs and produces video and interactive video training materials. The company is also at the forefront of the development of digital multimedia materials.

New Media is designing and authoring many CD-I programmes, including the Grolier Multimedia Encyclopedia. The company has also designed CD-I demonstration materials for Philips International on videotape, on CD-I disc and in print - the book, CD-I: A Designer's Overview, (1988, Kluwer & McGraw Hill).

Please cite as: Fletcher, D. (1988). The implications of laser optical disc formats in formal and distance education: Pictures, text and audio from silver discs. In J. Steele and J. G. Hedberg (Eds), Designing for Learning in Industry and Education, 1-5. Proceedings of EdTech'88. Canberra: AJET Publications.

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