[ IIMS 92 contents ]
Developing multimedia distance education courseware: Choosing software and hardware
Clive Murden, Leonard L Webster and John A. Harris
Monash University College Gippsland
This paper describes the factors addressed in choosing software and hardware for development and distribution of CD-ROM based multimedia study materials for distance education students. This work forms part of a major project currently being conducted at Monash Gippsland.
In this project a number of software packages, both high cost and low cost, were examined as possible choices. The features and limitations of these will be presented.
LinkWay, a low cost multimedia authoring system intended for use by authors with minimal computing skills, has been chosen for use in the first trial distance education materials. Experience with this package will be discussed, and examples of study materials produced with it will be demonstrated.
The choice of an appropriate hardware system for this project involved consideration of cost and availability to students, as well as technical aspects. The initial choice of hardware system and impact of continuing developments will be discussed.
The Monash Gippsland Distance Education Centre is undertaking a major project to research, develop and evaluate the use of multimedia CD-ROM in distance education. The evaluation stage of the project includes examination not only of educational effectiveness and student response to the technology, but also of economic factors for both the University and the student. Staff response, both to the idea of the incorporation of this technology in their courses and to personal involvement in developing study materials on CD-ROM is also to be assessed.
The project team has therefore been obliged to take account of all the above evaluation criteria in choosing hardware and software systems (both for development and presentation of study materials). This paper describes the selection processes undertaken and the choices made.
2. Software selection
2.1 Product requirements
2.1.1 Scale of study materials to be produced
This was not easy to define, given the range of courses currently offered by distance education and the range of teaching and resource materials used.
Given the possibility of placing materials for several different subjects on the same CD-ROM, and perhaps also the University Handbook or other support material, it was decided to purchase for evaluation one example of a full scale CD-ROM publishing software system, as well as examples of simpler software packages.
2.1.2 Media to be incorporated in study materials
Clearly the mix of media required for a given set of study material depends on the content and purpose of the material. However, to cover all likely applications, text, graphics, animation, sound and still image in full colour were seen as the basic media to be required. The software chosen therefore had to support these media.
2.2 Software selection criteria - full scale publishing systems
Table 1 shows the initial set of criteria devised for assessing the suitability of software packages for the project. This list was developed to take account of:
The initial approach taken was to forward the list of criteria, in the form of a questionnaire, to the producers of CD-ROM publishing software. Unfortunately the comprehensiveness of the list appeared to be counterproductive. Only one company provided a response covering the majority of the criteria and even then it was expressed in a different form.
Table 1: Factors to be considered in choosing full scale CD-ROM
- aspects particularly relevant to CD-ROM (eg. indexing types supported, CD-ROM simulation capability)
- aspects particularly relevant to multimedia (eg. graphics formats and screen types supported).
- aspects relevant to likely PC systems on which the materials would be run (eg. memory requirements, printer support)
- aspects relevant to software generally (eg. documentation supplied, licensing costs)
publishing software systems (comprehensive list)
- Text formats supported
- Word processing software supported
- Graphics formats and palette supported
- Third party language extensions
- Screen types supported
- Memory required on development platform
- Memory required to run applications
- Support for extended character set
- Animation capability
- Ability to simulate CD-ROM
- Ability to superimpose text over graphics
- Types of indexing supported
- Hypertext features
- Error correction capability
- Support for CD-I, CD-ROM(XA), videodisc
- Third party library support
- Provision of text editor in software
- Ability to link to other systems
- Support for icons and buttons
- Support for audio
- Need for supporting software (eg. Windows)
- Requirement for particular hardware
- Licence agreements and costs
- Royalty costs on products
- Availability of online help
- Courseware training
- Support for mouse
A reduced set of the most important criteria was then prepared and, utilising whatever information could be obtained from the producers, a table comparing various products was prepared.
2.3 Comparison and selection of full scale publishing systems
Twelve multimedia software systems suitable for full scale databases were examined and compared. Table 2 shows the outcome of this process for four of the products examined. For the products which showed strong potential to meet the project objectives and budget, missing information was sought by telephone and/or facsimile until sufficient data was available to decide on the most appropriate system for purchase.
Table 2: Comparison of full scale CD-ROM publishing software systems
|Company||Software Mart||Britannica Software||Nimbus||Crownin-shield|
|Product name||Media Mixer||SmarTrieve, SmartDOC||Romware||Mediabase|
|Text formats||ASCII||ASCII||ASCII||ASCII, DIF|
|Graphics||PCX, CGM, PIC, TIFF||Yes - no types specified||PCX, TIFF||PCX, Targa, BMT, GDP, TIFF|
|Screen modes||Mono, CGA, EGA, VGA||EGA minimum||EGA, VGA||EGA, VGA|
|Indexing ability?||Yes - Proximity, Boolean||Yes - Proprietary||Yes - Boolean, Search within search||Yes|
|Icons?||Yes - under "Windows"||Yes||No||Yes|
|Costs||$US6800 internal use - one operating system. $US10000 - 2-10 products||Not for sale at Dec 1990. Released for sale June 1991 $US25000 - 2-5 products||$US12525 per product published||$US7500 "Publisher", $US30000 "Developer"|
The system finally chosen for trial was Media Mixer ("Windows" version), marketed by Software Mart Inc. of Texas, USA. It is a subroutine library which can be used to prototype and build custom fielded data and multimedia CD-ROM retrieval engines. This product met the major criteria set by the project team at a relatively reasonable price. It also had the distinct advantage that full source code is provided, enabling the construction of user interfaces appropriate to any given application. This software is being prepared for trial in the first half of 1992.
2.4 Combined hardware - software systems
Some software systems are sold only in combination with hardware systems eg. CD Publisher system by Meridian Data. These were evaluated, but there was no obvious advantage to the project in the purchase of such a combined system, and the possible disadvantages of the lack of local service agents for the hardware eliminated this option.
2.5 Selection of small scale hypermedia software packages
The potential of Hypertext features to increase the level of students' interactivity with study materials and control over their learning is very significant. The project team was particularly keen to experiment with small scale hypertext authoring software to establish its uses within the project. The initial problem was finding suitable software packages. For reasons to be detailed in Section 3, the delivery systems chosen for the project are DOS based personal computers. Although a Hypertext software package called 'Hypercard' has been provided with Macintosh computers since 1987, DOS based Hypertext systems have been slow to develop. Our investigations during 1990 identified the following systems:
Three of these (Guide, Hyperwriter, LinkWay), in their latest versions, are true hypermedia systems. (Hyperties may also be a hypermedia system, but information about it has been very difficult to obtain).
- Guide by Owl International Inc. (USA)
- HyperWriter by Ntergaid Inc. (USA)
- Linkway by IBM (USA)
- Softbook by Karda Prints (W Aust.)
2.5.2 Selection criteria
While some of the selection criteria which are highly important in full scale publishing software for very large databases are much less relevant for the small scale packages (eg. modes of indexing available) most of the criteria previously defined can also be applied to this type of software. Table 3 compares the capabilities of the three hypermedia software systems.
Table 3: Comparison of features of small scale hypermedia software systems
|Company||OWL International Inc||Ntergaid||IBM|
|Text formats||ASCII, MS Word, RTF||ASCII||ASCII|
|Graphics formats||PCX, Windows Metafile, MS Paint, TIFF, bitmap||PCX, MGR||PCX|
|Screen modes||EGA, VGA, Super VGA||Mono - Super VGA||CGA, EGA, VGA, MCGA|
|Site licence available?||Only for > 10 copies||Site license $750||No|
|Runtime licensing costs||$40 per copy distributed||Nil||Nil|
All of the above products are seen as most appropriate for the development of small scale hypermedia study packages. All have been obtained for testing purposes. The very low purchase cost of LinkWay has led the project team to adopt it for the first trial CD-ROM to be produced.
3. Hardware selection
Two areas of hardware selection are involved in this project, the hardware platform for development of the materials and the hardware system to be utilised in presentation of the materials to students. Decisions in both these areas have been influenced by a number of factors, including the extremely rapid rate of change in capability and price of personal computers, the improved capabilities of multimedia software and the consequent increased hardware capability demanded by it, and the need to ensure compatibility of premastered material with the requirements of CD-ROM production facilities in Australia. What has become clear is that:
- satisfactory hardware systems for both development and presentation are currently available at a reasonable price, and
- the capability and price of these systems will continue to improve dramatically in the near future.
3.2 CD-ROM development hardware systems
3.2.1 Basic components required
Adkins (1986) has set down the hardware components required to construct CD-ROM preparation systems at various levels of sophistication, and hence cost.
He suggested appropriate brands or levels of the following hardware items for a multimedia production system:
- Computer (eg PC/AT, Micro Vax II, Sun)
- Hard Disk Unit (600 MB or 1.2 GB)
- Magnetic Tape Data Storage Unit (9 track, 1600 bpi or 6250 bpi)
- Graphics bit pad and video digitiser
- PCM Audio Processor (or Analog to Digital Converter) and VTR.
3.2.2 Hardware platform used for this project
The project team has assembled a hardware system along the lines proposed by Adkins, although not entirely by choice. The computer employed is an 80386 IBM clone operating at 25 MHz with 2 MB RAM, 40 MB hard disk and dual floppy disk drives. DOS based development hardware was chosen for compatibility with the materials presentation system chosen (see below). A 600 MB hard disk with a SCSI interface has been added. While DAT or Exabyte tape or magneto-optical disc were attractive alternatives to 9-track tape for storage of premastered material, only 9-track tapes can currently be handled by the sole Australian CD pressing company, Disctronics. A 9-track tape unit, again with SCSI interface, operating at up to 1600 bpi has therefore been added to the system. Audio capability is under investigation but not yet finalised and video digitisation is being carried out via software. This system has proved to be efficient and economic to date.
3.3 Hardware systems for CD-ROM materials presentation
3.3.1 Macintosh versus PC
The first decision to be taken with regard to the presentation platform was between Macintosh and PC. The decision to adopt a DOS based PC system was influenced by four factors:
- PC systems are currently much more commonly owned by, or accessible to, distance education students than Macintosh systems.
- The cost of purchase of colour Macintosh systems is significantly higher than PC systems.
- A greater range of CD-ROM drives was available for PC systems. (This situation is changing, with most recently released drive models being sold with interfaces for either Macintosh or PC).
- More academic staff within the University College are familiar with the PC environment and have PCs available to them than is the case for the Macintosh environment. The direct involvement of academic staff with the CD-ROM based materials is seen by the project team as the only way of increasing the use of these materials in the near future.
3.3.2 Computer system capacity and graphics mode
The initial philosophy of the project team was to attempt to match the computer system parameters as closely as possible to the level which might be expected to be commonly owned by or available to the distance education student. In early 1990 this was seen to be an XT machine with CGA (or at best EGA) screen, 640 kB of RAM and a 20 MB hard disk, a system which then sold at $1500 - $2000. However, this level of hardware would have made the use of colour photographic images impossible and the speed of operation of the programs very slow.
However, the changes in price structure of PC systems during the last 12-18 months has been dramatic. Graphics resolution has continued to increase, with Enhanced VGA mode (1024 x 768 with 256 colours) now being the most commonly advertised mode for the consumer market. The power of CPU chips has similarly risen, with 80286 and 80386 based machines now the norm. Systems incorporating these levels of CPU and graphics mode, 1 MB of RAM and 40 MB hard disk are now widely available in the price range $1500 - $2000. Thus the type of presentation system which multimedia packages need to be used effectively has now become the norm for the Australian consumer market, removing a substantial obstacle to the introduction of these packages in distance education. The project team has used 80286, 16 MHz PCs with 1 MB RAM, a 40 MB hard disk, external CD-ROM drive and VGA monitor as the platform for the trial study materials. This system matches the "Multimedia Personal Computer" (MPC) specification (Brennan, 1991), (except for the specified RAM capacity of 2 MB), now being marketed by a substantial group of hardware and software companies in the USA.
3.3.3 CD-ROM drives
Most CD-ROM drives have been designed as either internal drives to fit any half height drive bay in a computer, or as external drives, mounted in a separate case. The most important parameters in drive performance are seek time (ie. time to find the specified data) and reading speed (kb per second). The interface supported, particularly the availability of the generic SCSI interface, is another significant parameter. A set of benchmark tests has been devised (Hutchinson, 1991) and is now being applied to compare popular makes and models of drive.
An increasing range of internal and external drives, including compact portable drives designed for use with laptop computers, are now coming onto the market, priced at less than $A1000. Some of these drives have the capability of playing audio CD as well as CD-ROM, making them a feasible consumer item. Advertising of CD-ROM packages (drive plus several "encyclopaedic" software titles) for the consumer market began in Victoria in September 1991.
3.3.4 Input device
A pointing device such as a mouse is essential for ease and speed of control of hypermedia applications, but programs operating at deeper levels of learning and requiring more individualised responses and inputs from the student will require the use of a keyboard or equivalent. Pen based systems are now entering the market strongly and may well be ideal for hypermedia learning situations.
4. Development of multimedia courseware using LinkWay
4.1 LinkWay software
The first trial study materials on CD-ROM have been developed using the LinkWay software package, released by IBM in late 1990 and recently reviewed by Clarke (1991). LinkWay contains a simple word processor and paint program. It is mouse driven from a menu bar and is used to create folders containing pages of information
As the name implies, LinkWay is a true hypermedia authoring package, enabling any part of the screen to be defined as a "Button" (hyperlink). Buttons can link to a specified page in any folder, to a page containing a specified word, to a picture, or to "pop up" windows containing small amounts of text or containing a large document which can be edited. "Script" buttons enable a program to be run, eg. to drive a videodisc or play a segment from an audio CD.
The scripting language contained within LinkWay allows the use of variables, text field objects, buttons constants, expressions, operators and functions. Variables can be global (operational throughout a script) or local (discarded when the subroutine in which they are created returns to the calling script).
One of the unique features of the LinkWay environment is that when any object is placed on what is called the base page of a file (ie the first screen) that object will then be on every page of that folder. This was used to great benefit in placing functions which were needed throughout the application on the base page, thus ensuring that they were available to be referenced throughout the file.
IBM is promoting LinkWay as a tool which is simple enough for teachers to use to create learning materials for the classroom. This aspect was of particular interest in this project, as both resource limitations and the need to have academic staff committed to any alternative teaching materials produced will necessitate personal involvement by teaching staff in development of multimedia distance education materials. The low price of LinkWay and the absence of runtime licensing costs are undoubtedly part of this promotional approach to increase access to the software and applications using it.
Our experience to date is that LinkWay is an excellent starter package for hypermedia development. It is easy to use and enables the non-programmer to produce simple but meaningful small scale hypermedia applications in a reasonable time frame.
4.2 Limitations of LinkWay
The limitations of LinkWay arise mainly from its intended use - applications with limited size and complexity. Other limitations, such as the current preferential support for IBM hardware/software systems (eg. motion video adaptor boards, audio capture/playback boards) and the presence of a number of 'bugs' are not surprising in first release software. While there is no customer support for (and very limited experience with) LinkWay in Australia, the US customer support personnel and technical backup have been both prompt and helpful.
LinkWay is designed for small applications or large applications which can be broken down into a number of small logical parts. Because of this the History (Retrace) function is designed to record only the last nine pages (screens) that a user has visited.
The size of each LinkWay file also has limitations on its size. This relates to the number of different types of links/buttons that can be set up and the amount of text that can be displayed on any one screen.
The LinkWay design does allow for the quick prototyping of an application. The tools provided allow the painting of a screen very easily. This allowed for experimentation by the project team to establish the limits of the LinkWay environment. The other benefit of this was the fact that quick prototypes could be constructed to demonstrate different aspects of multimedia to staff members.
4.2.3 Limitations on text, images and colour
The maximum amount of text that can be displayed on any one screen is 79 characters by 20 lines. This is of course related to font size used.
LinkWay supports five screen modes - Mono, CGA, EGA, VGA and MCGA. In part of this project full colour still images were required. The only LinkWay screen mode which enables use of 256 colours is MCGA. Text accompanying the pictures was therefore restricted to a resolution of 320 x 200, an aspect on which users of trial materials have commented negatively. LinkWay does allow for the linking of files created with different screen modes, eg VGA text files and MCGA image files, but these cannot be mixed on the one screen. The calling of a picture onto a screen often affected what was currently displayed on the screen due to a different colour palette being loaded into the computer's memory. A solution for this problem was found.
4.2.4 Script language
The script language provided in the LinkWay environment is very macro based. The project team quickly found the limitations of this language, although some of these limitations were addressed in version 2.01 released this year. The script language does however allow linking to 'C' and 'assembler' programs developed outside the LinkWay environment. Also any DOS command or third party program can be called from the script language.
The problem that the project team found here was the standard problem on PCs, the lack of memory to link from LinkWay to run a large program. The script language allows the use of 300 variables within any one file. Each variable is limited to 32000 characters.
There is an allowance for only 10 levels of subroutine calls within the LinkWay environment. This presented problems in the current project. The script language has an upper limit of 4000 bytes per script program. This was a very severe limitation when developing a large system within Linkway. By some programming effort and passing of global variables it was possible to work around this limit.
The linking features of LinkWay, while powerful, do have some shortcomings. Links are possible from any page within any file to any page within the same file, or any other file. What is not allowed for is linking from any word or phrase direct to any other word or phrase. This can create confusion for students using the system and should be addressed.
To avoid the problem of the History function storing only the last nine screens, the project team devised its own "return from a link' procedure, allowing the user to move to many more levels (links) and still return to the starting screen.
4.3 Support tools for LinkWay
A LinkWay Author's Toolkit and Professional Developer's Toolkit are available, together with a Technical Reference Manual and Training Guide. The Professional Developer's Toolkit contains a range of tools such as animation, image resizing and format conversion, and video capture subroutines. These enhance the range of multimedia and hypermedia material which can be presented, to the point where CD-ROM may well be able to meet the learning needs of students at a range of levels for some time.
Whether or not multimedia and hypermedia realise their potential to alter both the materials and the methods of learning in distance education, and even on campus, remains to be seen. What is clear is that lack of access to appropriate software and hardware, at whatever level of sophistication is required, is no longer a constraint for either the developer or the user. The cost of these hardware and software systems is now very affordable, even cheap, and their capability impressive. The real challenge remains in the way we apply these systems.
6 . References
Adkins, A. L. (1986). Data preparation: From shoestring to super system. In Section III, Ch. 1 of Lambert, S. and Ropiequet, S. (Eds.), CD-ROM: The New Papyrus. Microsoft Press, Washington, USA.
Brennan, L. (1991). PC Week, March 23, 1
Clarke, A. (1991). Educational and Training Technology International, 28(1), 74
Hutchinson, R. (1991). CD-ROM Professional, 4(1), 31
|Authors: Clive Murden, Research Associate, School of Applied Science|
Leonard L Webster, Research Associate, School of Applied Science
John A. Harris, Head, Distance Education Development
Monash University College Gippsland.
Please cite as: Murden, C., Webster, L. L. and Harris, J. A. (1992). Developing multimedia distance education courseware: Choosing software and hardware. In Promaco Conventions (Ed.), Proceedings of the International Interactive Multimedia Symposium, 369-381. Perth, Western Australia, 27-31 January. Promaco Conventions. http://www.aset.org.au/confs/iims/1992/murden.html
[ IIMS 92 contents ]
[ IIMS Main ]
[ ASET home ]
This URL: http://www.aset.org.au/confs/iims/1992/murden.html
© 1992 Promaco Conventions. Reproduced by permission. Last revision: 5 Apr 2004. Editor: Roger Atkinson
Previous URL 4 Apr 2000 to 30 Sep 2002: http://cleo.murdoch.edu.au/gen/aset/confs/iims/92/murden.html