Multimedia Technology: An introduction, Lecture notes for Media Management
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Multimedia Technology: An introduction, Lecture notes for Media Management

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CHAPTER - 3

MULTIMEDIA TECHNOLOGY: AN INTRODUCTION

The objective of this chapter is to present a detailed account of multimedia

technology. The chapter commences with multimedia technology, its definitions,

genesis, components etc. It provides an overview of multimedia production, and its

application in various fields including libraries and information centers.

Computer technology has revolutionized the production of information

in the second half of the twentieth century. The traditional personal computers

have been text or data oriented until 1980s but after eighties a graphical

environment started. During1990‟s the power of information processing and

handling different media increased enormously and personal computers got

evolved as multimedia machines and the era of multimedia technology

emerged (Ramaiah, 1998). It has been said by computer technology research

reports 1993, that people retain only 20 percent of what they see and 30 percent

of what they hear. But they remember 50 percent of what they see and hear

(Keyas, 1994).

Multimedia technologies enable the users to integrate and manipulate

data from diverse sources such as video, images, graphics, animation, audio

and text on a single hardware platform. Now multimedia has become the latest

cultural phenomena in the information sector. The rapid ascent of multimedia

technology over the last decade has brought about fundamental changes to

computing, entertainment and education.

The exponential growth of multimedia technologies and applications has

presented the computerized society with opportunities and challenges that in

many cases are unprecedented. It is becoming more and more popular because

of the effectiveness of its applications in all aspects of human life. Multimedia

applications have progressed to the point of sparking a fundamental paradigm

shift in the very concept of information transfer and presentation.

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3.1 Multimedia: Definition

The term multimedia constituents of two words, „multi‟ and „medium‟.

Multi refers to many i.e. at least two. Media is the plural of medium. Medium

refers to storage, transmission, communication, representation, presentation,

input interaction and perception, meaning that it can refer to different level of

abstraction. It also refers to a basic information type like text, graphics, images,

audio, animation, video etc. Therefore multimedia is as an integration of many

types of media (i.e. text, graphics, images, audio, animation, video etc) on a

single medium in the same information unit.

The Columbia Encyclopaedia has defined multimedia as “in personal

computing, software and applications that combines text, high quality sound,

two and three dimensional graphics, animation, images, and full motion video.”

(Lagasse, 2000).

According to Vaughan “multimedia is any combination of text, sound,

animation and video delivered by computer or other electronic or digitally

manipulated means. It is a woven combination of digitally manipulated text,

photographs, graphic art, sound, animation, and video elements.” (Vaughan,

2008).

Newton defines multimedia as “the combination of different types of

media in the communication of information between two users and their

computers. The format in which the information for communication exists

differs, but it usually includes voice communication, sound processing and

image processing. Multimedia means that convergence of the technologies

from the different industries into a communication medium that presents the

synthesis of interactive computers, highly fidelity video and sound. Multimedia

is thus the combination of standard data processing with text, graphics,

animation, sound and video” (Newton, 1998).

Dahmer defines the term as “something that combines the capabilities

of technologies that used to be separate - it can combine things like text,

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graphics, sounds and still or motion pictures in a smooth way to present

information. Print, telecommunications, video, broadcasting and computers

have merged and the result is what we now call multimedia” (Dahmer, 1993).

The simultaneous use of two or more different forms of media (text,

graphics, animation, sound and video) for effective information communication

is referred as multimedia. Graphics and sound, digital or analog video,

animations, hypermedia, interactivity, computer games, virtual reality,

electronic books, CD-ROM, HDTV, telecommunications and many others have

all been terms associated with the definition of multimedia at one time or

another (Stubley, 1994). Multimedia is a technology engaging a variety of

media including text, audio, video, graphics and animation either separately or

in combination, using computers to communicate ideas or to disseminate

information.

3.2 Genesis of Multimedia

The genesis of multimedia can be traced back from some notable

inventions. The invention of printing press in 1450 by Gutenberg brought a

revolution in the growth of recorded knowledge. Radio transmission was

invented by G. Marconi in 1885, and he detected radio waves beamed across

the Atlantic in 1901, which is now a major medium for audio broadcasting.

In the area of still pictures, the evolution of microfilm was in 1839 and

negative film in 1841. Photography came into existence in 1851. Moving

pictures i.e. cinematographic film was invented in 1870. Sound recording discs

came into existence in 1877 and magnetic tape-recorder in 1898. Sound tape

was used first time in the year 1899. In 1908, video tape and Television were

invented. Electronic camera was invented in 1934 (Taylor, 1982).

Evolution of microcomputers in 1945 had made revolution in the field

of computer technology. Optical storage system was evolved in 1985, and it is

notable in this regard (Vaughan, 2008). Television was the new media for

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twentieth century, it brought the video and has changed the world of mass

communication.

Origin of multimedia is frequently connected with the emergence of

Memex. Memex is a mechanical device designed by Bush in 1945 for storing,

organizing and retrieving information in the form of text and graphics (Bush,

1945). Doug Englebert, in 1962, designed a system called NLS (oN Line

System) which had interactive multi-user editing and branching of different

files and texts having searching facility (Engelbart, 1993).

In 1965, Theodor Nelson had designed a system named as hypertext in

1965, which was based on the concept of Memex (Nelson, 1965). Hypertext

means a non sequential reading and writing, allowing authors to link

information, create paths through a corpus of related material, annotate existing

text, create notes and points readers to either bibliographical data or the body of

the referenced text. It is text in electronic form that take advantage of the

interactive capabilities (Conklin, 1987). When text is stored in a computer, the

computer‟s powerful processing capabilities can be applied to make the text

more accessible and meaningful. The text can then be called hypertext, because

the words, sections and thoughts are linked. The user can navigate through text

in a nonlinear way, quickly and intuitively.

Hypertext systems are currently used for electronic publishing and

reference works, technical documentation, educational courseware, interactive

kiosks, electronic catalogues, interactive fiction, text and image databases.

Another development in this field is hypermedia. A multimedia program

developed in a hypertext environment is hypermedia. It is simply the extension

of hypertext that incorporates other media elements in addition to text. With

hypermedia systems, author can create linked corps of materials that include

text, static and animated graphics, video, sound, music etc. (Yankelovich,

Haan, Meyrowit & Drucker, 1988). The basic difference between hypermedia

and multimedia is in the organization and the linkages of the information

fragments. The information fragments in the multimedia are organized linearly

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whereas in hypermedia, these are organized non-linearly with links to each

other (Ramaiah, 1992).

Theodor Nelson started another project named as XANDU in 1960s, a

global literary system aimed as instantaneous repository and delivery system

for the published works like text, graphics, audio, video etc., so that any user

may rapidly get any frame or whole work (Nelson, 1980; Gregory, 1983). In

late 1970s, Van Dam designed a File Retrieving and Editing SyStem (FRESS)

by incorporating the best ideas of Engelbart‟s NLS (oN Line System) and

Hypertext Editing System (Van Dam, 1971). This was followed by another

system INTERMEDIA, designed by Meyrowitz at Brown University for

conducting research on use of hypertext in teaching (Yankelovich et al., 1988).

At the start of 1990s multimedia was meant as combination of text with

document images (Andleigh & Thakrar, 2003).

Multimedia technology got revolutionized with the introduction of

Internet. In 1991, Tim Berner Lee developed a global hypertext project known

as World Wide Web designed to allow people to work together by combining

their knowledge in a web of hypertext documents. He is the primary inventor of

the World Wide Web and HTML, the system of text links and multimedia

capabilities that made the Internet accessible to mass audiences (Berner-Lee,

n.d.).

In twenty-first century multimedia is used on internet for various

multimedia applications. Now most of the websites on internet have

multimedia capabilities. Multimedia blogs, audio and video archives, podcasts,

multimedia galleries, webcasts, multimedia in social networking websites etc

are today‟s common applications of multimedia on internet.

3.3 Components of Multimedia

There are five components of multimedia i.e. text, sound, images,

animation and video. These are explained in detail as under (Vaughan, 2008).

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3.3.1 Text

Text or written language is the most common way of communicating

information. It is one of the basic components of multimedia. It was originally

defined by printed media such as books and newspapers that used various

typefaces to display the alphabet, numbers, and special characters. Although

multimedia products include pictures, audio and video, text may be the most

common data type found in multimedia applications. Besides this, text also

provides opportunities to extend the traditional power of text by linking it to

other media, thus making it an interactive medium.

(i) Static Text

In static text, the words are laid out to fit in well with the graphical

surroundings. The words are built into the graphics just like the graphics and

explanation given in the pages of the book, the information is well laid out and

easy to read. The learners are able to look at the pictures and read the textual

information, as they are available on the similar screen (Kindersley, 1996).

(ii) Hypertext

A hypertext system consists of nodes. It contains the text and links

between the nodes, which define the paths the user can follow to access the text

in non-sequential ways. The links represent associations of meaning and can be

thought of as cross-references. This structure is created by the author of the

system, although in more sophisticated hypertext systems the user is able to

define their own paths. The hypertext provides the user with the flexibility and

choice to navigate through the material.Text should be used to convey

imperative information and should be positioned at appropriate place in a

multimedia product. Well-formatted sentences and paragraphs are vital factors,

spacing and punctuation also affects the readability of the text. Fonts and styles

should be used to improve the communication of the message more

appropriately.

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3.3.2 Image

Images are an important component of multimedia. These are generated

by the computer in two ways, as bitmap or raster images and as vector images.

(i) Raster or Bitmap Images

The most common and comprehensive form of storage for images on a

computer is a raster or bitmap image. Bitmap is a simple matrix of the tiny dots

called pixel that forms a raster or bitmap image (Vaughan, 2008). Each pixel

consists of two or more colours. The colour depth is determined by how much

data, in bits is used to determine the number of colours e.g. one bit is two

colours, four bits means sixteen colours, eight bits indicates 256 colours, 16

bits yields 65,536 colours and so on. Depending on the hardware capabilities,

each point can display from two to millions of colours. Comprehensive image

means that an image looks as much as possible like the real word or original

product. This means that the proportion, size, colour, and texture must be as

accurate as possible. Bitmap formats are Windows Bitmap (BMP), Device

Independent Bitmap (DIB), and Windows Run Length Encoded (RLE)

(Hillman, 1998).

(ii) Vector Images

Vector images base on drawing elements or objects such as lines,

rectangles, circles and so forth to create an image. The advantage of vector

image is the relatively small amount of data required to represent the image and

therefore, it does not requires a lot of memory to store. The image consists of a

set of commands that are drawn when needed. A bitmap image requires the

number of pixels to produce appropriate height, width and colour depth, the

vector image is based on a relatively limited number of drawing commands.

The falls drop of vector images is the limited level of detail that can be

presented in an image (Hillman, 1998). Mostly used vector format is Windows

metfile in windows operating system.

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Compression techniques are used to reduce the file size of images that is

useful for storing large number of images and speeding transmission for

networked application. Compression formats used for this purpose are GIF,

TIFF and JPEG.

3.3.3 Animation

Animation consists of still images displayed so quickly that they give

the impression of continuous movement. The screen object is a vector image in

animation. The movement of that image along paths is calculated using

numerical transformations applied to their defining coordinates. To give the

impression of smoothness the frame rate has to be at least 16 frames per

second, and for natural looking motion it should be at least 25 frames per

second. Animations may be two or three dimensional. In two dimensional

animation the visual changes that bring an image alive occur on the flat X and

Y axis of the screen, while in three dimensional animation it occurs along the

entire three axis X, Y and Z showing the image from all the angles. Such

animations are typically rendered frame by high-end three dimensional

animation softwares. Animation tools are very powerful and effective. There

are two basic types of animations, path animation and frame animation.

(i) Path Animation

Path animations involve moving an object on a screen that has a

constant background e.g. a cartoon character may move across the screen

regardless any change in the background or the character.

(ii) Frame Animation

In frame animations, several objects are allowed to move simultaneously

and the objects or the background can also change.

The moving objects are one of the most appropriate tools to enhance

understanding, as they allow the learner to see the demonstration of changes,

processes and procedures (Earnshaw & Vince, 1995). Animation uses very

little memory in comparison to digital video as it consists of drawing and

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moving instructions. Animation is very useful for such multimedia applications

where moving visuals are required, but where digital video may be unsuitable,

unnecessary, or too expensive in terms of disc space or memory.

3.3.4 Sound

Sound is probably the most sensuous element of multimedia. It is

meaningful speech in any language, from a whisper to a scream. It can provide

the listening pleasure of music, the startling accent of special effects, or the

ambience of a mood setting background. It can promote an artist, add interest

to a text site by humanizing the author, or to teach pronouncing words in

another language. Sound pressure level (volume) is measured in decibels,

which is actually the ratio between a chosen reference point on a logarithmic

scale and the level that is actually experienced.

(i) Musical Instrument Digital Identifier (MIDI)

Musical Instrument Digital Identifier (MIDI) is a communication

standard developed in the early 1980s for electronic musical instruments and

computers. It is the short hand representation of music stored in numeric form.

MIDI is the quickest, easiest and most flexible tool for composing original

score in a multimedia project. To make MIDI scores sequencer, software and

sound synthesizer is needed. A MIDI keyboard is also useful for simplifying

the creation of musical scores. Its quality depends upon the quality of musical

instruments and the capabilities of sound system. It is device dependent

(Vaughan, 2008).

(ii) Digital Audio

Digitised sound is sampled sound. The every nth fraction of a second, a

sample of sound is taken and stored as digital information in bits and bytes.

The quality of this digital recording depends upon how often the samples are

taken (sampling rate) and how many numbers are used to represent the value of

each sample (bit depth, sample size, resolution). The more often the sample is

taken and the more data is stored about that sample, the finer the resolution and

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quality of the captured sound when it is played back (Vaughan, 2008). The

quality of digital audio also relies on the quality of the original audio source,

capture devices, supporting software and the capability of playback

environment.

The main benefit of audio is that it provides a channel that is separate

from that of the display (Nielson, 1995). Sound plays a major role in

multimedia applications, but there is a very fine balance between getting it

right and overdoing it (Philips, 1997). Multimedia products benefit from digital

audio as informational content such as a speech or voice-over and as special

effects to indicate that a program is executing various actions such as jumping

to new screens. The three sampling frequencies used in multimedia are CD-

quality 44.1 kHz, 22.05 kHz and 11.025 kHz. Digital audio plays a key role in

digital video.

3.3.5 Video

Video is defined as the display of recorded real events on a television

type screen. The embedding of video in multimedia applications is a powerful

way to convey information. It can incorporate a personal element, which other

media lack. The personality of the presenter can be displayed in a video

(Philips, 1997). The video may be categorised in two types, analog video and

digital video.

(i) Analog Video

Analog video is the video data that is stored in any non-computer media

like videotape, laserdisc, film etc. It is further divided in two types, composite

and component analogue video.

Composite Analog Video has all the video components including

brightness, colour, and synchronization, combined into one signal. Due to the

composition or combining of the video components, the quality of the

composite video is resulted as colour bleeding, low clarity and high

generational loss (Hillman, 1998). Generational loss means the loss of quality

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when the master is copied to edit or for other purpose. This recording format

was used for customer analog video recording tape formats (such as Betamax

and VHS) and was never adequate for most multimedia presentations

(Vaughan, 2008).Composite video is also susceptible to quality loss from one

generation to other.

Component analog video is considered more advanced than composite

video. It takes different components of video such as colour, brightness and

synchronization and breaks them into separate signals (Hillman, 1998). S-VHS

and Hi-8 are examples of this type of analog video in which colour and

brightness, information are stored on two separate tracks. In early 1980s, Sony

has launched a new portable, professional video format „Betacam‟ in which

signals are stored on three separate tracks (Vaughan, 2008).

There are certain analogue broadcast video standards commonly used

round the globe. These are National Television Standard Committee (NTSC),

Phase Alternate Line (PAL), Sequential Colour with Memory (SECAM) and

HDTV. In the United States, Canada, Japan NTSC standard is used, while in

United Kingdom, China, South Africa PAL is used. SECAM is used in France.

A new standard has been developed known as High Definition Television

(HDTV) which bears better image and colour quality in comparison to other

standards.

(ii) Digital Video

It is the most engaging of multimedia venues, and it is a powerful tool

for bringing computer users closer to the real world (Vaughan, 2008). Digital

video is storage intensive. A high quality colour still image on a computer

screen requires one megabyte or more of storage memory. To provide the

appearance of motion, picture should be replaced by at least thirty times per

second and the storage memory required is at least thirty megabyte for one

second of video. The more times the picture is replaced, the better is the quality

of video.

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Video requires high bandwidth to deliver data in networked

environment. This overwhelming technological bottleneck is overcome using

digital video compression schemes. There are video compression standards as

MPEG, JPEG, Cinepak and Sorenson. In addition to compressing video data,

streaming technologies such as Adobe Flash, Microsoft Windows Media,

QuickTime and Real Player are being implemented to provide reasonable

quality low bandwidth video on the web. QuickTime and Real Video are the

most commonly used for wide spread distribution.

Digital video formats can be divided into two categories, composite

video and component video. Composite digital recording formats encode the

information in binary (0‟s and 1‟s) digital code. It retains some of weakness of

analogue composite video like colour and image resolution and the generation

loss when copies are made.

Component digital is the uncompressed format having very high image

quality. It is highly expensive. Some popular formats in this category are

„Digital Bitacam‟ and D-5 developed in 1994 and DVCAM developed in 1996.

There are certain standards for digital display of video i.e. Advanced

Television System Committee (ATSC), Digital Video Broadcasting (DVB),

and Integrated Services Digital Broadcasting (ISBD). ATSC is the digital

television standard for the United States, Canada and South Korea, DVB is

used commonly in Europe and ISBD is used in Japan to allow the radio and

television stations to convert into digital format (Molina & Villamil, 1998).

Video can be used in many applications. Motion pictures enhance

comprehension only if they match the explanation. For example, if we want to

show the dance steps used in different cultures, video is easier and more

effective than to use any graphics or animation (Thibodeau, 1997).

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3.4 Production of Multimedia Resources

3.4.1 Infrastructure

Multimedia resources are based on the ability of the computer to

capture, process, and present text, pictures, audio and video. Selection of

proper hardware, software and file format for developing multimedia product is

based on the budget and type of content in the product and delivery

requirements. Following is a description of infrastructure requirement for

producing multimedia resources.

3.4.1.1 Hardware Requirement

The special hardware requirement can be described in four categories i.

e. Input devices, Output devices, Storage devices and Communication devices.

(i) Input Devices

Input devices usually used for the production of multimedia resources

are as follows.

(a) Keyboard

A keyboard is the most common method of interaction with a computer.

The most common keyboard for PCs is the 101 style, although many styles are

available with more or fewer special keys, LEDs, and other features.

(b) Mouse

A mouse is the standard tool for interacting with a graphic user

interface. The buttons on the mouse provide additional user input, such as

pointing and double-clicking to open a document, or the click and drag

operation, or to move to and select an item on a pull down menu, to access

context sensitive help.

(c) Touch screen

Touch screens are monitors that usually have a textured coating across

the glass face. This coating is sensitive to pressure and registers the location of

the user‟s finger when it touches the screen initiative to pressure and registers

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the location of the user‟s finger when it touches the screen. Touch screens are

excellent for applications in a kiosk, at a trade show or in a museum delivery

system.

(d) Scanner

Scanner is the most useful equipment used in a multimedia project. It

may be flat bed, hand held and drum scanners. The most commonly used

scanner for multimedia application is colour flatbed scanners that provide

resolute of 600 dots per inch (dpi) or better.

(e) Optical Character Recognition Device

After scanning, a document can be converted into a word processing

document on the computer without retyping or rekeying, with the help of OCR

system. OCR system uses a combination of hardware and software to recognise

characters. Some examples of OCRs are omni page from Scansoft, Recore

from Maxsoft-Ocron. The OCR terminal can be of use to a multimedia

developer because it recognizes not only printed characters but also

handwriting. This facility may be beneficial at a kiosk or in general education

environment where user friendliness is a goal, because there are growing

demand for a more personal and less technical interface to data and

information.

(f) Voice Recognition System

Voice Recognition systems can be used for the hands-free interaction

with the computer. These behavioural biometric systems usually provide a

unidirectional cardioid, noise cancelling microphone that automatically filters

out background noise and learn to recognize voice prints. These systems can

trigger common menu events such as save, open, quite, print and other

commands that are more specific to the application.

(g) Digital Camera and Video Camera

Digital cameras capture the still image or video of a given number of

pixels (resolution) and the images are stored in the camera‟s memory to be

uploaded later to a computer. The resolution of digital camera is determined by

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megapixel rating. Video camera is a camera capable of recording live motion

video with audio for later display. Data may be uploaded from the camera‟s

memory using a USB cable connected to the computer.

(ii) Output Devices

Following is a brief description of output devices used in a multimedia

project.

(a) Monitors

The monitors for a multimedia application must be high-end, large

screen graphics monitor and liquid crystal display. Serious multimedia

developers often attach more than one monitor to their computer, using add-on

graphics boards. This is because many authoring systems allow working with

several open windows at a time. So one monitor may be dedicated to view the

work the developer is designing, and editing tasks can be performed in

windows on other monitors that do not block the view of the work.

(b) Audio devices

All the computers are equipped with an internal speaker and a dedicated

sound chip, and they do are capable of audio without additional hardware. To

abate advantages of inbuilt stereo sound external speakers are required. Altec

Lansing‟s three piece amplified speaker system is designed for multimedia

applications.

(c) Video devices

Video display devices, often called graphics adapters, enable the

computer to present information on monitors capable of displaying up to 16

million colours. Television pictures can be displayed on the computer by

installing a video digitizing board.

(d) Projectors

Projector is required to show the presentation to large number of

viewers. Cathode ray tube projectors, liquid crystal display, digital high

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processing projectors, and liquid crystal on silicon projectors may be used for

the multimedia applications.\

(e) Printers

With the advent of reasonably priced colour printers, a hard copy output

has entered the multimedia scene. Many printers are available in the market i.e.

laser printer, solid-ink printer, dye-sublimation printer, liquid inkjet printer and

printers based on toner technology. Laser printers are the best in terms of

quality output.

(iii) Storage Devices

Multimedia data requires very high storage capacity. The storage

devices used are given as follows.

(a) RAM

The Random Access Memory should be very good for graphics, audio

and video production and writing multimedia products. Graphics memory also

called VRAM (Video random access memory) for high resolution colour

display may be used.

(b) Hard Disc

There should be relatively fast hard drive systems for processing

graphics, audio and video. Now fast, less expensive and large capacity HDD

are available in the market. 120GB Hard disc is recommended for multimedia

production.

(c) Magnetic Tapes

It is a plastic ribbon which is usually ½ inch or ¼ inch wide, and 50 to

2400 feet long. Data are recorded on the tape in the form of tiny invisible

magnetised and non-magnetised spots on the coated surface of the tape. The

tape ribbon is itself stored in reels or in small cartridge or cassette. Four mm

digital audio tape is most widely used type of magnetic tape in multimedia

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applications. It uses a tape ribbon of 4mm and 60 or 90 meters long enclosed in

a cartridge.

(d) Magnetic Disc

Magnetic disc is a thin plate made of plastic usually coated on both sides

with a magnetisable recording material. The information written on it can be

erased or reused indefinitely. The information stored can be read many times,

without affecting its quality. Floppy disc and hard disc are examples of

magnetic disc. Most popular magnetic discs used in multimedia application are

Zip disc, Jaz disc, super disc etc.

(e) Optical Disc

Optical discs can store extremely large amount of data in a limited

space. An optical-disc storage system consists of a rotating disc, which is

coated with a thin metal or some other material that is highly reflective. Laser

beam technology is used for recording and reading data on the disc. These are

also called laserdiscs. It is found in the form of CD-R, CD-RW, and DVD. CD-

R is Compact Disc Recordable., CD- RW is Compact Disc Rewritable, and

DVD is Digital Video Disc. There are three types of DVD, DVD-RW, DVD-

Video and DVD-ROM. CDs and DVDs are the best for multimedia storage

because of its huge storage capacity.

(f) Pen Drive and External Hard Disc

The latest development in storage is the evolution of pen-drive and

external hard-disc.

(iv) Communication Devices

Multimedia data file size, especially for graphics, audio and video are

quite large. Therefore the key issue for multimedia communication is

bandwidth. Band width is the amount of information that can be transmitted

across a network of computers within a stipulated period of time. It is measured

in kilobits per second (kbps) or megabits per second (mbps). Communication

systems have created two classes of multimedia products, synchronous or real

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time and asynchronous. Synchronous applications are able to transmit and

receive data in real time allowing the end user to view or hear data as it is being

captured or created. Asynchronous applications use a store and forward method

in which data is transmitted and stored for future. Primary communication

devices for multimedia are as under (Hillman, 1998).

(a) Modem

Modem modulates and de-modulates analog signals. The modem speed

is the most important consideration in communicating multimedia files. These

files contain the graphics, audio and video and usually it is needed to move as

much data as possible in a short time. Today‟s standards dictate at least a 56

kbps modem. Compression saves significant transmission time and cost over

long distance. Fifty six kbps V.90 depends on hardware based compression

algorithm to crunch the data before sending it and decompressing it upon

arrival at the receiving end (Vaughan, 2008).

(b) Network Devices

For higher transmission speed by telephone Integrated Services Digital

Network (ISDN) is recommended for multimedia. ISDN lines offer a 128 kbps

data transfer rate. These are used for internet access, networking and audio and

video conferencing. Now a faster technology known as DSL technology using

a dedicated line has overtaken ISDN in popularity.

As there are so many variables in selecting hardware for a multimedia

platform, a group of companies formed an organization called the Multimedia

PC Marketing Council (MPC) in 1990 to set minimum standards for

multimedia hardware. MPC Level-1 published in 1990 dictated that a system is

considered as Level 1 system with configuration as 16 MHZ 386SX or

compatible microprocessor, 2 MB of RAM, 30 MB Hard disc, 3.5-inch high-

density Discette drive, single speed CD-ROM drive with a 150 KB per second

data transfer rate, 8-bit soundboard, VGA compatible display adapter, Colour

VGA compatible monitor, 101 key keyboard, two-button mouse, standard

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serial and parallel ports, MIDI port, joystick port and support for either

Microsoft Windows version 3.0, with multimedia extensions, or for Windows

version 3.1.

These standards were updated in 1993 with Level-2 specifications, and

again updated in 1995 as MPC-3. The MPC-3 standard delineates the

specifications for multimedia as 75 MHz Pentium Processor, 8 MB RAM, 540

MB Hard disc, 3.5-inch high-density Discette drive, Quad speed CD-ROM

drive with a 600 KB per-second data transfer rate, 16-bit, wave-table, MIDI

sound card, MPEG-1 hardware and software capable of 30 frames per second,

352 by 240 pixels, 15 bits per pixel (Vaughan, 2008). Current machines have

surpassed even this level, with storage space now measured in terabytes

standard on most PCs, RAM in gigabytes, and up to a 200 MHz processor

speed on the Pentium chip.

3.4.1.2 Software Requirement

Multimedia softwares are authoring tools, which provide an important

framework for organizing and editing the elements of multimedia including

graphics, sound, animation and video. Tools for authoring and programming in

multimedia applications include Director, Aurhorware Professional,

CourseBuilder, Flash, Supercard, Hypercard, and Film Maker etc. A brief

description of some of the authoring softwares are as follows.

(i) Adobe Director

It is a software tool for multimedia authoring. The software is used to

create interactive games, interactive learning materials, applications, kiosks,

DVDs, CDs and the web.

(ii) CREATE Together

This is a multimedia environment that integrates creation, collaboration,

communication, problem solving, and publishing in one seamless tool. It can be

used to create animated games, randomly generated puzzles, interactive

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simulations, searchable multimedia databases, hyperlinked presentations,

training materials.

(iii) MediaBlender

It is a multimedia authoring package which allows users to create their

multimedia projects, helping them organize and communicate information and

ideas using a wide variety of media. MediaBlender can be accessed from any

computer with internet access. Also the software can be hosted on any server

for better performance, and load a stand-alone application on computer for use

without an Internet connection in client-server mode.

(iv) MediaWorks 6.2

MediaWorks combines simple-to-use video, sound, animation and paint

editors with a powerful multimedia authoring program. It can easily create

amazingmovie-type productions that are difficult or not possible in other

consumer-level movie and slide show editors, and precisely-timed linear and

interactive presentations without the learning curve and expense of high-end

media editing and authoring tools.

(v) PlayMo

PlayMo is an authoring tool that allows the creation of highly interactive

rich media content from a wide range of source files such as still images, video

clips, audio clips, 3D models, CAD models and more. PlayMo's intuitive

WYSIWYG editing functions make it easy to embed complex interactivity into

models to accurately recreate the functionality of real-world objects, requiring

no coding.

(vi) Multimedia Builder

It is a multimedia authoring system that allows to create autorun CD

menus, multimedia applications on CD-ROM, demos, kiosks, Computer based

training, presentations, MP3 players etc.

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3.4.1.3 File Formats for Multimedia

The following is an outline of current file formats used for the

production and delivery of multimedia.

(i) Text Formats

(a) RTF (Rich Text Format)

RTF is a proprietary document file format with published specification

developed by Microsoft Corporation in 1987 for Microsoft products and for

cross-platform document interchange.

(b) Plain text

Plain text files can be opened, read, and edited with most text editors.

Examples include Notepad (Windows), edit (DOS), ed, emacs, vi, vim, Gedit

or nano (Unix, Linux), SimpleText (Mac OS), or TextEdit (Mac OS X). Other

computer programs are also capable of reading and importing plain text. Plain

text is the original and ever popular method of conveying e-mail. HTML

formatted e-mail messages often include an automatically-generated plain text

copy as well, for compatibility reasons.

(ii) Image Formats

(a) TIFF (Tagged Image File Format)

This format is common in desktop publishing world, and almost all

software packages support it. Recent versions of TIFF allow for image

compression, and the format is handy for moving large files between

computers.

(b) BMP (Bitmap)

This format came into use with Windows 3.1. It is uncompressed and

can be quite large. For this reason, BMP is seldom used for the large or high-

resolution images.

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(c) DIB (Device Independent Bitmap)

This format is similar to BMP, allows files to be displayed on a variety

of devices.

(d) GIF (Graphics Interchange format)

GIF is acompressed image format developed by CompuServe, an online

information service. Most computer colour images and backgrounds are GIF

files. This compact file format is ideal for graphics that use only few colours,

and it was once the most popular format for online colour photos. The GIF

format uses an 8-bit Colour Look Up Table to identify its colour values. This

format is widely supported by several shareware viewers and converters.

(e) JPEG (Joint Photographic Experts Group)

This format was designed for maximum image compression. JPEG uses

loosy compression, which refers to a compression scheme that actually looses

some of the data needed to reconstruct the image. It works well on

photographs, naturalistic artwork, and similar material but does not work well

on lettering, simple cartoons, or live drawings. The rationale behind loosy

compression is that the human eye does not miss the lost information.

(f) TGA (Tagra)

This was the first popular format for high-resolution images. The name

comes from the original Targa board, the first true-colour video board. Most

video-capture boards support TGA, as do most high-end paint programs.

(g) PNG (Portable Network Graphics)

An extensible file format for the loss less, portable, well compressed

storage of raster images. PNG provides a patent free replacement for GIF and

can also replace many common uses of TIFF. PNG is designed to work well in

online viewing applications, such as the worldwide web, so it is fully

streamable with a progressive display option.

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(iii) Digital Audio File Formats

(a) WAV (Waveform Audio File Format)

The most popular audio file format used mainly in windows for storing

uncompressed sound files. It can be converted to other file formats like MP3to

reduce the file size.

(b) MP3 (MPEG Layer-3 Format)

MPEG Layer-3 format is the most popular format downloading and

storing music. The MP3 files are compressed to roughly one-tenth the size of

an equivalent WAV file.

(c) OGG

A free, open source container format that can be compared to MP3 files

in terms of quality.

(d) AU

It is a standard audio file format used by Sun, Unix and Java. The audio

in AU file format can be compressed.

(e) AIFF (Audio Interchange File Format)

A standard audio file format used by Apple which is like a WAV file for

the Mac.

(f) WMA (Windows Media Audio)

It is a popular windows media audio format owned by Microsoft and

designed with Digital Right Management (DRM) abilities for copy protection.

(g) RA (Real Audio Format)

Real Audio format is designed for streaming audio over the Internet.

The digital audio resources are usually stored as a computer file in

computer‟s hard drive or CD-Rom or DVD. There are multitudes of audio file

formats, but the most common formats are wave files (.WAV) and MPEG

Layer-3 files (.MP3), WMA and RA. Following are the commonly used digital

audio file formats (Rajashekharan & Nafala, 2009).

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(iv) Digital Video File Formats

(a) AVI (Audio/Video Interleave)

AVI is the file format used by Video for Windows, one of three video

technologies used on personal computers. In AVI, picture and sound elements

are stored in alternate interleaved chunks in the file.

(b) MPEG (Moving Picture Experts Group)

MPEG is a group of people that meet under the International Standards

Organization (ISO) to generate standards for digital video and audio

compression. Established in 1988, the group has produced MPEG-1, the

standard on which Video CD and MP3 are based, MPEG-2, the standard on

which such products as Digital Television set top boxes and DVD are based,

MPEG-4, the standard for multimedia for the fixed and mobile web and

MPEG-7, the standard for description and search of audio and visual content.

Work on the new standard MPEG-21 "Multimedia Framework" has started in

June2000. Technically speaking MPEG is not a storage format but standards

for digital video and audio compression.

A video file format is a standard for encoding digital video, audio and

some auxiliary information into a file. In contrast to audio and image formats,

most video file formats allow a variety of codecs, both audio and video to be

used (Pathak, 2006).

3.4.2 Steps in Multimedia Production

Multimedia production requires a significant amount of time and careful

planning. Adequate planning assures that the project will proceed smoothly and

follow a reasonably designed schedule for completion and will certainly

communicate the information to the target audience. For the development of

complex multimedia projects, there are following phases (Vaughan, 2008)

(i) Conceptual Analysis and Planning

The process of making multimedia starts with a vision, high site or an

idea, which is the conceptual ignition point. Conceptual analysis involves

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identifying a relevant theme, budget and checking the availability of content on

that particular theme. Other criterion like how amenable is the content to the

multimedia treatment and issues like copyright are also considered in

conceptual analysis. Based on the available budget the theme should be

finalized and a thorough planning should be made.

(ii) Project design

After finalizing the theme, specific goals, objectives and activities are to

be laid down for the multimedia project. Goals are general statements, while

objectives are specific statements of the anticipated project outcomes.

Activities are the actions done in order to implement an objective. Specific

people are responsible for their execution and there is a time frame and cost

binding their development. A very important element that should be defined at

this stage is the potential target audience of that proposed title, which will

determine how the content should be presented. Strengths and weakness of the

project should be stated and the ways should be identified to maximize and

minimize them respectively.

(iii) Pre-production

Depending on the planning and design, it is required to develop the

project. There are following steps in pre-production.

(iv) Budgeting

Money is not an infinite resource, therefore a detailed budget should be

estimated for each step of the production of multimedia title. Typical budgeting

heads are cost of personnel, advisors and consultants, equipments (hardware

etc.), software, audio/video production, royalties, legal expenses,

communication expenses, travel expenses, typing and publishing.

(v) Multimedia Production Team

The production of the fine quality high-end application requires a

specialized team and its best efforts. As developing a multimedia project is a

teamwork, this team consists of a number of members i.e. Production Manager,

Content Specialist, Script writer, Text Editor, Multimedia Architect, Computer

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