Multimedia 3

Design Considerations for Multimedia

Tannenbaum - Chapter 7

Development• Multimedia development products are complex,

multifaceted, and multidisciplinary, requiring the blending of skills and techniques from many different fields.

• The design of multimedia productions employs many of the same methods as design in other disciplines, in addition to consideration unique to designing for interactivity.

Design• Design is defined as “creative process that

draws upon elements, experience, and knowledge from many different sources” (Tannenbaum, 1998, p 388).

• Blum (cited in Tannenbaum) defines design as a complex human process, subjected to continuing change (which often is controlled artificially), and deeply dependent on experience and knowledge.”

Architectural Design

• Group considerations of objectives and potential solutions by architects, engineers, and clients, and solitary thinking and drawing by an individual architect.

• Have to have flexibility between architect and client and a merging of visions.

Cuff (1991)• Described six problems inherent in architectural

design with may also appear in multimedia design:– design in the balance– countless voices– professional uncertainty– perpetual discovery– surprise endings– a matter of consequence.

Engineering Design...

• Builds much more on past designs than does architecture.

• Concerned more with failure - predicting, identifying, and preventing errors in a design that may have serious consequences.

• Replete with individual decision points and choices.

Graphics and Creative Arts

• A long process entailing many versions of the same work, each slightly altered and improved until the designer is satisfied with the product.

• Cannot be merely the uncritical application of design rules which include those – governing lighting or arranging a scene, organizing or

structuring a paragraph or chapter, or applying or avoiding certain color combinations.

• Must include creativity and occasionally breaking the rules when that produces a better outcome.

Software Engineering Design• The careful creation of objectives and

specifications for the software to be written.

• The choice of algorithms and data structures follows from these specifications, as does the design of the user interface.

• Structures for the design phase can be any or none of the following:– process-oriented, data flow analysis, or data-

oriented.

How it all Begins• Multimedia design begins with a need and an idea.

– Most frequently the idea comes from someone other than the designer.

• The first step in the development involves the definition of the specifications including– clarifying the problem and beginning the iterative

specification process through a number of revisions until a reasonable detailed specification is agreed upon by the stakeholders in the project.

• The specification process defines what is to be accomplished by the multimedia production while the design process defines how it will be accomplished.

• Alternately, the specifications may call for evaluation of the user’s accomplishment of certain instructional objectives as the basis for branching to new material, in which case, the design phase will then involve creating the details of the evaluation exercises an screens.

(Tannenbaum, 1998, 393-394)

Multimedia design

• Shares many characteristics from each of these as well as having some unique to the field.

• Unlike architecture and engineering, multimedia productions are not intended as permanent creations.

• Multimedia designers need to integrate elements from many different disciplines such as – graphic, video, and screen design, human-computer

interface development, instructional and curriculum planning, computer science and software engineering, and many others.

Multimedia as a Medium

Interactivity (Furness and Barfield, 1995, pp. 5-6, cited in Tannenbaum,

1998)

• The interface between the human and the machine can be thought to exist in “direct and “indirect” paths.– Direct paths are those which are physical or

involve the transfer of signals in the form of light, sound or mechanical energy between the human and the machine.

– We usually think of the direct pathways as the information medium.

Interactivity con’t

• The indirect pathways deal with the organization of symbols according to internal models which are shared by the human and the machine. These models cause the data elements conveyed on the display to have meaning or “semantic content.”

• We can think of the indirect pathways as the message that is transmitted through the medium. Our ability to input control actions into the machine makes the medium interactive, in that messages can be sent in two directions.

• In order to achieve smooth, effective interactivity between a user and a multimedia production, many different elements must be considered.

• Multimedia designers must always consider the user first and make the computer do what is necessary to achieve the desired interactivity.

What makes things interactive?

• The four C’s– Control,– Consistency,– Context, and – Corroboration

• can be used to evaluate whether a project is interactive at all and, if so, whether its interactivity design is successful.

Does Communication Occur Between the User and the Computer?

• According to Cathcart and Gumpert (1985) cited in Tannenbaum, 1998, p. 397, human-computer interaction occurs in three ways:– unobtrusive functions,– computer-facilitated functions, and– person-computer interpersonal functions.

The Dyadic Model• The interaction between a person and a

computer can only imitate dyadic interpersonal communication - – a computer prompts the user for input– the computer asks questions and the user responds– People interface with the computer through a

keyboard or other input device– The computer responds via visual displays, error

messages, or simulated speech.

Dyadic Differences• A computer is programmed, therefore,

communication that occurs between the computer and its user is to an extent predetermined, predictable, structured, non-dynamic, and repeatable.

• The degree of control is much less ambiguous between computer and user than person-to-person interactions. The computer discards everything it cannot process or does not need.

Interactivity Interface

• According to Marcus (1993) the user interface must achieve effective communication via the use of – Metaphors,– Mental models,– Navigation of models,– Look, and – Feel.

• A multimedia producer should attempt to achieve communication within the production that is as natural (interpersonal) as possible, but not at the cost of requisite precision.

• Multimedia designer needs to strive for interactivity that is as close as possible to human interactions, within the constraints of budget and cost-effectiveness.

• Interactive interfaces often employ metaphors to help users remember and use various functions.

• Common metaphors include “windows,” desktops,” and “buttons.”

• Interface designers are constantly employing new metaphors.

• A metaphor should be familiar to the user, have a single clear meaning or implication, be naturally and locally related to the function it denotes, and be employed only to facilitate interactivity, not because it is cute or clever.

More on Metaphors

• Icons are a form of metaphor.

• Unless metaphor and icons are clear and understandable, with no distracting implications, users may be mislead by them into “cognitive train wrecks.”

• Research in the fields of educational, gestalt, and applied cognitive psychology has much to contribute to successful design for interactivity.

• Many finding in Gestalt psychology are of consequence for interface design.

• Color associations, connotations, and preferences are important in interface design.

• Educational psychologists have found that people learn more efficiently when more than one modality is employed.

• However the number and choice of modalities must be carefully coordinated with the subject matter and the users involved.

• Learning theories also stress that students should be active learners; multimedia productions are clearly one effective method for providing the most effective reinforcement is positive and intermittent, or irregularly spaced.

• Interface building tools help multimedia design by providing templates and code generators for generic forms of interfaces.

• There is a cognitive model of interface building, the GOMS (Goals, Operators, Methods, and Selection rules) model, that has been used with some success in the analysis of certain human cognitive activities and may provide a basis for certain interactive interface designing.

• It is important for the multimedia interface designer to consider the intended users in terms of their culture and preferred style of interaction.

• The choice of style(s) to be employed should be dictated by the nature of the material and the preferences of the intended users.

• It is often considered good practice for a designer to include two or more styles of interaction simultaneously.

• Absolute, inviolable rules for graphics and screen design are not possible.

• Every situation requires a designer to exercise creativity.

• General principles do exist and are as follows:

General Principles - 1

• The more time spent on comprehensive and detailed planning, the better.

• Develop clean, attractive, informative titles.

• Keep screens simple, conveying one major idea per screen.

• Avoid lengthy textual material, which should be provided in printed format rather than on-screen.

General Principles - 2• Keep screen design uncluttered, using

adequate margins and sufficient white space.• Use images carefully, avoiding distractions

and irrelevant material• Minimize variations in font size and style to

avoid detracting from the message.• Choose type fonts and sizes that are clear and

easy to read, yet direct emphases appropriately

General Principles - 3• Avoid the use of excessive numbers of colors, using

no more than two or three per screen, and normally only for emphasis.

• Use bright colors for the foreground, pale colors for the back ground.

• Avoid clashing colors.• Charts and graphs should be carefully crafted to

display the relevant data and clarify the salient points, avoiding clutter, distractions, and distortions.

Schneiderman (1987)• Eight golden rules of dialog design

– Strive for consistency

– enable frequent users to use shortcuts

– offer informative feedback

– design dialogs to yield closure

– offer simple error handling

– permit easy reversal of actions

– support internal locus of control

– reduce short-term load.– Cited in Tannenbaum, 1998, pp. 430-431

Users and Systems Make Errors• Multimedia designers must plan accordingly,

endeavoring to prevent and avoid errors, if possible, and providing useful error messages and minimally disruptive remedies.

• To the extent possible, a program should be able to recognize different forms of error, so that it can provide helpful suggestions to the user to correct the problem.

• Designers should provide as much useful information and opportunity for error correction as possible for users, such as “help” screens and “undo” commands.

• Error messages should be written clearly, be specific, be constructive in helping suggest appropriate remedies, and always be courteous and not condescending.

Intelligent Interfaces• Four elements are needed for broad-based intelligent

interface– a natural language interface– an inference engine that operates within the context of the

current interaction to access the appropriate portions(s) of – a knowledge base, and– a knowledge-base maintenance tool.

• Such an interface is currently impractical for most multimedia production both in terms of development costs and operating resources.

Hypermedia

• Hypermedia consists of nodes, where content is stored and displayed, and links, which provide connections among the nodes to facilitate a user’s access to the content in his or her chosen sequence.

• The nodes and links for a network navigation of which is accomplished with a program called a “browser.”

• Under different circumstances, using different combinations of hardware and software, and with different objectives for the production, sometimes hypermedia is the best solution for a multimedia program; sometimes it is not.

• Because multimedia productions consist of several different media that need to be displayed for the user simultaneously and because the timing of the various media must be coordinated, synchronization is an important consideration in multimedia development.

• The perception of the synchronization of three elements (temporal, spatial, and content) needs to be flawless, not perfect in fact. (see Tannenbaum, 441)

WWW• Critics have called challenges to multimedia production

a step back because some capabilities that are available for standard multimedia are not available on the Web.

• The basis of the limitations is the bandwidth available on the WWW.

• Design decisions for multimedia on the Web need to be made to maximize the strengths of the Web delivery of material and the interactivity if affords, rather than consideration of absolute fidelity of image or sound reproduction.

• Careful attention is needed to ensure that WWW does not become MMM (multimedia mediocrity).

The End

Control

• First, users should have some level of control ovre an experience - where they are going, how they get there, and how easily they can sopt and start.

Consistency

• Second, the look and feel of behavioral elements - what’s on the screen, and audio or mucis as weel - should be consistent.

Context

• Third the interactivity should have a context. Is it related to the information around it?

Corroborate

• Fourth, the interactivitiy should reflect the nature of the content - that is, it should corroborate the content. – If there’s a video on a Web site or a CD-ROM,

is the video conducive to understand the content?

– Or should that material be in the form of text?

Unobtrusive Functions

• Occur when a computer is present in the interaction but not noticed– use of a telephone,– digital sound recordings,– scanners in grocery and other retail outlets

Computer-facilitated Interaction • Occurs when a person uses a computer to

expedite communication (i.e., people are communicating through or via a computer rather than with a computer– e-mail,– voice-mail,– presentation software

• allow the control of space and time throught the computer and/or a network.

Person-computer Interpersonal Functions

• Treat the computer as partner in the communication act or the person and the computer are thought of as a dyad, communicating with one another. No longer is the person communicating with another by means of the computer, but rather the person is interacting with the computer– ATMs,

– automated telephone operators for directory assistance or credit card calls,

– working with a word processor,

– playing a computer game, or interacting with a multimedia production.

Metaphors

• Fundamental terms, images, and concepts that are easily recognized, understood, and remembered.

Mental Model

• Appropriate organization and representation of data, functions, work tasks/activities, and roles.

Navigation of Model

• Movement among data, functions, work tasks/activities, and roles depicted in the model that provide speedy access and facilitate comprehension.

Look

• Appearance characteristics that efficiently convey information to the user in an appealing manner.

Feel

• Interaction techniques that operate efficiently and provide an appealing perceptual experience.