Metaphors for authoring interactive multimedia

With the introduction of interactive multimedia learning materials and the movement towards constructivism as an underpinning philosophy for the design of democratic learning environments, the organising metaphor of the authoring system has become critical in the effective design of the final learning environment. There is a need for easy to use development tools which incorporate alternative metaphors in the development process. There exist a multitude of authoring tools such as Authorware Professional, ToolBook, Spinnaker Plus, Director and HyperCard, these are examined for the limits to their applicability in providing access to information structures and the instructional strategies available to the learner as they move through and create new knowledge constructs within these environments. In this paper, a new tool for authoring "MediaPlant" which has its roots in constructivist thinking is examined as an alternative authoring environment. This package is unique in that it allows multiple levels of representation of the component information; it supports the designer by enabling the unit of analysis to be an object, a screen or an integrated information element which might include multiple screens but with a unified information structure. Exploring the Nardoo, a product developed with this tool, will be demonstrated.

Introduction

With the introduction of interactive multimedia formats, and the perceived need for easy to use development tools, a multitude of authoring tools such as Authorware Professional, ToolBook, Oracle Media Objects, Macromind Director, Digital Chisel and HyperCard have been developed. Many of these packages have a constraining model of how they present information and manage interactions. Simply stated, it is instructive to consider the models that each is best suited to provide for both the developer and the user of the final package. A further complication is that many of the tools do not allow cross platform development and the speed of the resulting instructional packages is always going to be limited by the interpretive layer.

Consider the underlying metaphor for some of these tools.

• Authorware uses a two screen display of structure and presentation, the structure is represented as a flow chart and the essential model is that an element is presented and the responses is entered and judged for an action. The structure of each project is essentially a view of the world as a flow chart within flow chart or one component flow chart moves to another component flow chart.

• Director uses the multiple window environment in which resources are created or managed onto an operatic metaphor of a stage. 'Me management is through a time dependent score which allows objects to be treated as members of the opera company and moved through time and backwards and forwards from backstage to front stage.

• HyperCard, Oracle Media Objects both employ a screen based metaphor, onto which objects are placed and under each is some script which dictates what will happen if that object is selected clicked or moved in some way. While these tools have an immediacy they lack the overall structure representations of the previous two.

• Digital Chisel and Hyperstudio add further constraints to the screen based metaphor of HyperCard and provide a highly structured set of interactions, all preset and limited in their complexity of response. However, like Authorware, they include an instructional management system as an automatic feature of the package.

MediaPlant as an authoring environment

The key elements of the authoring environment are that the tool includes

• rapid prototyping of design ideas and restructuring of ideas simply and efficiently.
• design elements that can be added through either menu selection or copy and paste facilities
• design elements that can be edited, reused, and repurposed simply and efficiently
• hypertext linking from element to element
• extensibility so that new features can be added when necessary
• visual representation of the application and the authoring environment available at all times.

The memory requirements for MediaPlant are 8-10 MB for the development program (the more the better) and approximately 2 MB for the runtime application. The runtime application memory allocation with depend on a number of factors with the basic break up of the following form.

The runtime application
code, resources, internal data structure (including cache) - 1 MB

Image resources loaded typically consisting of
a screen image (300 kB for full screen)
off screen buffer (300 kB for full screen)
buttons (50 kB)
additional pictures (150 kB)

Total approximately 2 Megabytes

The development program metaphor is based upon a tree file structure with pull down menus for the authoring process. A graphic design interface has not been developed for this stage of the environment development. The file structure metaphor, has a drag and drop and editing widow facility for each element. The structure is completely versatile in that each element below the container level is named either with a presumed location, which is its tree structure location, or can be given a prefix file location. This structure has a number of advantages in that it allows multiple use of resources, allows the developer to manage the data elements in whichever way best suites their preferred design style and with use of the 'drop and drag facility' allows easy and rapid rearrangement of the data elements.

Figure 1: A tree file structure used in MediaPlant with pull down menus for the authoring process

Exploring the Nardoo and problem solving

Figure 2: The Personal Digital Assistant Notebook

• Decide precisely on the quantity and selection of text to be copied into their notes. This is either through making a selection and then 'grabbing' it into the PDA or by using a 'drag and drop' technique where the target text is selected or highlighted and 'dragged' into the notes module of the PDA.

• Use marker buttons as pointers to video, audio or picture information which can be displayed within the PDA's viewer along with any linked information. For example, by copying a picture of a wombat into their notes, the student is able to move throughout the information landscape within the package and very quickly view the picture of the wombat as well as its associated text within the PDA's viewer merely by clicking on the marker button within their notes. User defined portions of the reference text material displayed within the viewer is able to be selected and copied into the notes also.

• Gather video material, place 'in' and 'out' point markers within it and display it within the PDA thus increasing the student's ability to be more selective in what they choose to use in response to an investigation.

• Manipulate marker buttons and text within the notes areas, via 'drag and drop', to facilitate the reordering of ideas in the process of building an investigative response in the form of a report, explanation, procedure etc.

• Use text style tools, within editable text notes, providing the opportunity to use font colour, style and size as organising criteria within the notes. For example a student may recognise that a certain combination of text attributes is representative of newspaper clippings or they may choose to colour information they write or gather from a particular perspective in a special colour.

The package also provides the ability to record thoughts and impressions 'on the fly' whilst examining media stories. This provides the potential for students to reorganise or revise their thoughts to better 'make sense ' of what they see and hear. Students are able to document their emerging ideas in support of an investigation or problem solving exercise whilst viewing different media. This provides support in the formulation of new schemata in the process of accommodating the new information.

By way of illustration, whilst viewing a video segment related to the issue of water conservation, students may have their attention drawn to a specific aspect such as better ways to manage water use within the household. The Nardoo PDA provides the means by which they are able to search out other related information (text, graphics, radio/television reports) and store it within their notes 'alongside' previously captured information. The different perspective's represented within the source media items can be viewed, edited and brought into context within the student's framework of notes they are making. They can, in addition, model water user using one of the three simulators built in. (Figure 3.)

Figure 3: A personal water use simulator

A writing genre template (discussed in the following section) can also be loaded directly into the text tablet into which portions of the student's notes may be copied or dragged. Notes from prior sessions can be loaded into the text tablet and used in support of current investigations. Being able to store and report thoughts and impressions derived from media experiences by using the media itself (actual video/audio and pictures not just text representations of the media) provides a more powerful means of reformulating ideas (Kenny and Schroeder, 1994, p 965).

The multimedia collection, editing and presentation facilities offered within Exploring the Nardoo are extensive and present a great potential for students to become manipulators of multiple media. New avenues are opened for expression for those who choose to use the facilities within the package. We are aware however, as Kenny and Schroeder (1994) point out "learner's not accustomed to this technique and multimedia facilities will require instruction in its use" before they become proficient with the technique but once accustomed to it the student has a powerful process at their disposal to gather, organise and illustrate their ideas. Support for teachers and students in the use of these features will be modelled through walk through movies made available through the help system and also detailed in support notes available in reference books within the package.

Conclusion

Reference

Authors: John Hedberg, Barry Harper, Robert Wright and Grant Farr Interactive Multimedia Development Laboratory Faculty of Education, University of Wollongong Wollongong NSW 2522 Email: J.Hedberg@uow.edu.au Please cite as: Hedberg, J., Harper, B., Wright, R. and Farr, G. (1996). Metaphors for authoring interactive multimedia. In C. McBeath and R. Atkinson (Eds), Proceedings of the Third International Interactive Multimedia Symposium, 16-21. Perth, Western Australia, 21-25 January. Promaco Conventions. http://www.aset.org.au/confs/iims/1996/ek/hedberg1.html