Unit 3: Multimedia

The Development Process

What is Multimedia?• An interactive piece of software using several

types of media:– Text– Graphics (photographs or illustrations)– Audio (synthesised or digitised)– Video– Animation

• Multimedia Applications can be:– Linear or non-linear– Simple or extremely complex– For example:

• PowerPoint presentation• Sophisticated and basic web pages• Multimedia games

The Development Process/Cycle

Maintenance

Design may change if application does not work as expected

Analysis

Design

Implementation

Testing

Documentation

Evaluation

Analysis Stage

• This stage is make it absolutely clear what the project is supposed to do.– The aims of the application– Who will be using it?– What will be in it?– How will it be distributed?– How much money can be spent?– How long have you got?– Input/output?

• At the end of the stage a requirements specification will be produced.

Design Stage

• Navigation structure?• The HCI (Human Computer Interface)• What does each screen look like?• What media elements will be

included?

Storyboards may beproduced for this.

Implementation Stage• Make it:

– Create and combine all the media elements using the pre-decided authoring software.

Testing Stage• Does each screen and link work as

expected?– If not can it be fixed or does it have to

have the design altered.

Documentation Stage

• Write the documentation:

– The technical guide• What are the hardware requirements

– The user guide• Advice on how to use the software and

provide users with any other help.

Evaluation Stage• Does it meet the specifications made

at the analysis stage?

Maintenance Stage• Fixing any bugs that have been

found after its released.• Adapting and updating the

application to suit clients needs.

Unit 3: Multimedia

The Development Process

The Development Process Mnemonic

Maintenance

Analysis

Design

Implementation

Testing

Documentation

Evaluation

A

Dance

In

The

Dark

Every

Monday

Text editor: • Application is created using plain text

– e.g. Creating simple web pages using HTML.

WYSIWYG editors: • Previewing applications under

development to check that What You See Is What You Get.– Eg PowerPoint to create a presentation

Methodologies used in creation of multimedia applications

WYSIWYG

Text Editor

WYSIWYG Vs Text Editors

Advantages Disadvantages

Text Editor Simple and places less demands on system.

Provides greater control over the application

Difficult to Visualise output

Dependant on programming or text-based commands knowledge

WYSIWYG Easy creation and editing of application

Ideal for beginners

Complex software that puts higher demands on system.

Software tends to be expensive

Authoring Software • Application can be customised using:

– Program code or scripting– Icon based setting up of properties (without the

need to learn programming code)

Presentation Software• Enables the creation of a sequence of slides• Allows hyper linking to different slides or

files

Methodologies used in creation of multimedia applications

• Who makes authoring software?– Macromedia

•Flash, Dreamweaver and Director

– Microsoft•FrontPage

– Adobe•GoLive

– Others•Mediator, HyperStudio, etc

Methodologies used in creation of multimedia applications

• Who makes presentation software?– Microsoft

•PowerPoint (Most common)

– Others•LiquidMedia•Cre8•Many others exist but not common

Methodologies used in creation of multimedia applications

Authoring Vs Presentation

Advantages Disadvantages

Authoring Advanced features give developer more control over final application

Difficult to learn, special training generally required

Can be difficult to debug complex application

Presentation Simple commands

Easy to learn

Limited features

Unit 3: Multimedia

The Development Process

Displaying Multimedia Data

Distribution Technologies

• Web Pages• Embedded into Web pages

– ActiveX Object– Visual Basic Script– Java Applet– JavaScript Program

Displaying Multimedia Data

Distribution Technologies (cntd)

• Stand alone Program (executable)• Multimedia file using player

software– Macromedia Flash or Shockwave– PowerPoint– QuickTime

Distribution Medium

• Web pages on the Internet• Web pages on an Intranet• CD-ROM• DVD• Digital Broadcast System

Displaying Multimedia Data

Embedded Data• Applications include files for sound, video etc• These are combined (embedded) into the

actual program file itself

Advantages DisadvantagesFile management is easier as there is only one file

Easier to implement security

File could be very large

Entire file must be downloaded before it can be played

Individual data items cannot be updated separately

Displaying Multimedia Data

Displaying Multimedia Data

Streamed data

• Data broadcast over a network– radio stations broadcast over the Internet– View film clips

• Played as it is received• No need to download entire file before

listening/viewing it• Requires a plug in e.g. Real Player

Codecs & Container Files

Codecs (Compressor/Decompressor)

• Main purpose is to reduce the file size while keeping as much quality as possible

• Enables faster downloads

• Often built into programs but sometimes require downloaded as a add-in

Codecs & Container Files

Container File

• Contains several compressed files.

• This can be transmitted over a network and the individual files regenerated at the receiving end

• Much more convenient than sending multiple files

• A ZIP file is an example of a container file