Flexible CD-ROM Design: A Template ModelBarry Richardson and Andrew Brown, Dianne Wuillemin and Sue Burney
Department of Psychology, Monash University
Several interactive virtual psychology laboratories were developed on CD-ROM using Macromedia Authorware and Director. Features common to each laboratory were treated as programmed modules or units that together comprised a template able to accommodate change to itself, as well as change to the content of a particular CD-ROM. With little or no understanding of programming or software authoring, content designers or compilers (e.g. academic staff) can then insert their own text, graphics, video, and audio material. This paper describes the basic features of such a template under development at Monash University. Key features are (1) structure, determining how the user navigates through the content, (2) function - a set of interactions the user accesses, and (3) visual layout - the way the pages look. A "wizard" is planned to allow creation of modules in a manner similar to the way PowerPoint presentations are prepared.
Jones and Jo (1998) observe that the use of interactive multimedia can offer students a non-linear approach to course material and the freedom to work at their own pace.
Another group consists of those wishing to keep their university jobs and denied the luxury of deciding whether or not to use multimedia because it may be the only way to do as they are told - to teach more students, with fewer staff, while improving product quality in a competitive market place.
In the Department of Psychology of Monash University, we are designing CD-ROMs and web-based material for students studying: (1) on campus and attending traditional lectures and laboratory classes; (2) on campus and by flexible delivery using CD-ROMs for virtual laboratories and video tapes of lectures; (3) by distance in Australia using CD-ROMs at weekend schools; and (4) by distance overseas. The latter group is targeted for "true" distance delivery meaning that attendance on campus is never required.
To provide material for these mixed modes of delivery and, in particular, to meet the challenge of mounting a completely offshore accredited psychology program, our multimedia products need to be not only of high quality but flexible in a number of ways.
We cannot afford to produce "one off" CD-ROMs to be discarded when out of date or in need of improvement, and we would like to take advantage of time and money-saving software developments as they arise. In addition, our resources, both human and financial, are not sufficient to meet the demand now placed on us for the production of virtual laboratories.
These considerations point to the need for flexibility of at least two different kinds. Firstly, we need flexibility that allows insertion and deletion of material (content) in order to correct errors, update factually, and improve our products with respect to efficiency and content delivery without major disruptions to the underlying program structure. Secondly, we need flexibility of the kind that allows non-programmers to produce basic CD-ROMs. This would give a measure of control and independence to the "content" people and would relieve some of the pressure placed on technical/programming staff. We are working on a template to offer both of these kinds of flexibility.
The procedure we are following is to keep the foundation or fundamental framework of each CD-ROM as it is produced, change this for the better (we hope) with each successive production, and gradually produce a "polished" template that is a balance between fixed and flexible features. The best balance of freedom and restriction will depend on the discipline and purpose of the CD-ROM but there are some general design principles to help point the way to an optimal design.
A CD-ROM template: a definition
A template represents an attempt to make as much use as possible of re-usable code and media so that time and money is saved in future productions or modifications. Each CD-ROM is based on the same template which continually evolves as previous productions are updated and improved.
The template is essentially a set of selected commands, programmed units, or modules that multimedia teams judge to be common to all of the products likely to be needed in the future.
If a perfect template existed, it would remain fixed while content changed.
For example, in psychology, there is often a need to present auditory or visual stimuli to an observer who is asked to respond either by saying something or by pressing a key. Accuracy and latency of such responses are frequently used as dependent measures and certain standard statistical tests are used to analyze data.
Facilities for presenting stimuli and collecting responses can be built in as modules available to an academic content compiler who has had training in neither basic programming nor the use of authoring tools. However, such a content compiler knows the duration of the stimulus they want presented on the computer screen, what response they want measured, and how they want responses recorded. The template, if properly designed, permits this person to "plug in" their own text, graphics, video clips, and stimulus-response parameters, as well as offering access to statistical packages for data analysis. Similar research or demonstration paradigms exist in other disciplines.
The modules can each have default settings chosen on the basis of experience about what is most likely to be required by most content compilers in the discipline. (Such experience is best found in a team of academic and technical staff working together.) However the template must nonetheless be flexible enough to accommodate changes in both the nature and range of settings available beyond those invoked by default.
Choosing the appropriate balance between defaults, range of choices within a fixed menu, and what the menus will be, is not all that easy.
One danger of a template design is that it might make it easy to create a limited range of multimedia products, but hard to expand beyond the restrictions of the template. Thus, the template itself must be flexible as well as the modules within it but not so flexible that the compiler's task becomes one of programming rather than the more simple task of compiling (plugging in the text and graphics you want).
We have decided to err on the side of restriction, and therefore simplicity, because gradual expansion into more complicated designs seems less prone to disaster than trying to prune a design that is too complex.
The following are design features to be considered:
The structure of a multimedia system determines the path the user follows to view the content. Major structures (and a combination of these is often used) are:
In most of our CD-ROMs a branched hierarchical structure is either used or accessible in the template if the need arises.
The content of each prototype has been divided into four major sections. Each section and subsection can be renamed but the number of sections has been restricted to four, at least for now. They are: Introduction, Task, Results, and Summary, but these sections could be renamed for another discipline or purpose. Whether four sections is enough remains to be determined but is an example of where default settings, in this case four sections, may be too restrictive.
The sub sections are arranged into a sequence of pages accessible only via a hypertext contents page that is itself accessible only via a section heading. This is another example of deliberate restriction to gain simplicity.
The functions within a template design are divided into three categories which are:
The functions require a lot of planning and probably undergo more changes than other features of a template because they depend so much on content.
Each of our prototype CD-ROMs was used to test varying functions. The basic functions chosen for navigation were "next page", "previous page", "exit" and section selection buttons. These proved to be sufficient for a large number of purposes.
The content presentation functions (part of the Utilities category) include an efficient system for retrieving media from one digital video file. Although each virtual laboratory involves a different experiment and, therefore, different functions, each has in common a loop to present stimuli and request a response that can be judged for accuracy or timed for latency. Also, results of the experiment or task are recorded and displayed in graphs or tables for report or further analyses. These are examples of common features that become programmed modules in the template because they are useful over and over again.
Interaction can be as simple as a quiz with results, and as complex as choosing parameters upon which the success or failure of a virtual experiment will depend, or changing the display in novel ways to explore previously unstudied effects.
The visual layout of the template depends upon what functions and structures there are, and which need to be displayed. After trying a number of visual designs in successive prototypes, we chose one that seems to be emerging as standard in an increasing number of multimedia products. As shown in Figure 1, it consists of:
Figure 1. Visual layout of the template
The final form of background evolved over successive prototypes as the optimal location of content, titles, and navigation buttons became clearer on the basis of the results of pilot studies.
All prototypes were designed using the screen resolution of 640 x 480 pixels. This simplifies production and restricts the amount of information (clutter) presented in any one page.
The content regions are set so that a limited amount of text can be presented at any one time. This space is on the left of the screen and allows for about 150 words which we plan to test as optimal or otherwise. To the right is an area of 320 x 240 pixels in which visual media (e.g. cartoons, graphics, animations and videos) can be displayed. The visual media display area is also an interactive zone (See Figure 2).
Figure 2. Sample screen layout
Small groups of students have completed questionnaires on some of our early attempts and later prototypes were assessed by 1200 students studying in a variety of modes as listed above. Results indicated that performance did not differ in a way that could be attributed to our CD-ROMs or mode of delivery. This is neither good nor bad news but at least we have no evidence to suggest that multimedia is associated with lower marks.
One group of offshore students who received all available CD-ROMs and other multimedia material performed better than their onshore counterparts though this could be explained by a variety of potentially confounding variables. One or two students discovering that multimedia products were to replace lectures sought to move to another campus in order to access live lectures despite having video tapes of lectures available.
We are currently designing ways of more accurately and meaningfully assessing the pros and cons of the use of our multimedia products.
Due to the complex programming behind each module, it is not easy for the average academic to program an entire module, however one possibility is to build a wizard module building kit.
Currently the template is an Authorware file that is the starting point for developing a new module. To expand on this idea we could create an Authorware file that needs no further editing. Instead, we store all content (images, video, audio, text) externally in a folder on a CD-ROM and along with the external media, an initialization text file that contains information for the Authorware template file. The information would be created by running a wizard program which asks the compiler (developer) a number of questions and provides a number of options. Upon running the template, the information file is read and the template becomes a new module.
Regardless of its final form, we are confident that a template allowing non-programmers to produce good quality multimedia CD-ROM material will be as much in demand as the products themselves.
Jones, V. and Jo, J.H. (1998). Interactive multimedia based on learning theories to enhance tertiary education. Proceedings of the 2nd International Conference on Computational Intelligence and Multimedia Applications, Monash University. 432 - 437.
UniServe Science News Volume 11 November 1998
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