Chapter 1

Multimedia Introduction and Evolution

It's as large as life, and twice as natural!
— Lewis Carroll, Through the Looking-Glass

Introduction

Multimedia can have a many definitions these include:

“Multimedia is a combination of various elements, such as text, images, video, sound, and animation.”

“Multimedia means that computer information can be represented through audio, video, and animation in addition to traditional media (i.e., text, graphics/drawings, images).”

“Multimedia is the seamless integration of text, sound, images of all kinds and control software within a single digital information environment.”

Tony Feldman, multimedia consultant

A good general working definition for this module is:

“Multimedia is the field concerned with the computer controlled integration of text, graphics, drawings, still and moving images (Video), animation, audio, and any other media where every type of information can be represented, stored, transmitted and processed digitally.”

Multimedia is one of the most innovative and fast-growing areas of information technology and design, providing exciting career opportunities. Multimedia combines different media – images, film, sound, words and animation – into an interactive package that presents information in a variety of forms, and allows people to use it in a way that best suits them.

Multimedia is more than just an effective combination of two or more media. Multimedia is about using a personal computer (PC) as an effective tool for integrating a rich blend of media types and making it possible to bring these elements together in an interactive and cohesive manner.

Multimedia System

A Multimedia System is a system capable of processing multimedia data and applications. A Multimedia System is characterized by the processing, storage, generation, manipulation and rendition of Multimedia information.

Characteristics of a Multimedia System

Multimedia presentations broadcast may be a live or recorded multimedia presentation. Broadcasts and recordings can be either analog or digital electronic media technology. Digital online multimedia may be downloaded or streamed. Streaming multimedia may be live or on-demand.

Multimedia games and simulations may be used in a physical environment with special effects, with multiple users in an online network, or locally with an offline computer, game system, or simulator.

The various formats of technological or digital multimedia may be intended to enhance the users' experience, for example to make it easier and faster to convey information. Or in entertainment or art, to transcend everyday experience.

Enhanced levels of interactivity are made possible by combining multiple forms of media content. In addition to seeing and hearing, Haptic technology enables virtual objects to be felt. Emerging technology involving illusions of taste and smell may also enhance the multimedia experience.

A Multimedia system has four basic characteristics:

§ Multimedia systems must be computer controlled.

§ Multimedia systems are integrated.

§ The information they handle must be represented digitally.

§ The interface to the final presentation of media is usually interactive.

Desirable Features for a Multimedia System

The following features a desirable for a Multimedia System:

Very High Processing Power — needed to deal with large data processing and real time delivery of media. Special hardware commonplace.
Multimedia Capable File System —needed to deliver real-time media — e.g. Video/Audio Streaming.
Special Hardware/Software needed – e.g RAID technology.
Data Representations — File Formats that support multimedia should be easy to handle yet allow for compression/decompression in real-time.
Efficient and High I/O —input and output to the file subsystem needs to be efficient and fast. Needs to allow for real-time recording as well as playback of data. e.g. Direct to Disk recording systems.
Special Operating System —to allow access to file system and process data efficiently and quickly. Needs to support direct transfers to disk, real-time scheduling, fast interrupt processing, I/O streaming etc.
Storage and Memory — large storage units (of the order of hundreds of Gb if not more) and large memory (several Gb or more). Large Caches also required and high speed buses for efficient management.
Network Support — Client-server systems common as distributed systems common. Software Tools — user friendly tools needed to handle media, design and develop applications, deliver media.

Components of a Multimedia System

Now let us consider the Components (Hardware and Software) required for a multimedia system:

Capture devices — Video Camera, Video Recorder, Audio
Microphone, Keyboards, mice, graphics tablets, 3D input devices, tactile sensors, VR devices. Digitizing Hardware
Storage Devices — Hard disks, CD-ROMs, DVD-ROM, etc
Communication Networks — Local Networks, Intranets, Internet, Multimedia or other special high speed networks.
Computer Systems — Multimedia Desktop machines,
Workstations, MPEG/VIDEO/DSP Hardware
Display Devices — CD-quality speakers, HDTV,SVGA, Hi-Res monitors, Colour printers etc.

Multimedia Application Definition

A Multimedia Application is an application which uses a collection of multiple media sources e.g. text, graphics, images, sound/audio, animation and/or video.

Evolution of Multimedia

The increasing power of electronic circuitry in workstations, personal computers, and consumer electronics, in conjunction with the decreasing cost of high-bandwidth and low-latency communication, have created a large momentum to develop sophisticated multimedia applications as well as to provide new types of services to businesses and homes. These capabilities involve improving user interfaces to many traditional applications as well as creating futuristic applications such as virtual environments and augmented reality.. The basic idea behind the latter types of applications is to immerse a user in an imaginary, computer-generated virtual world or to augment the real world (i.e., via augmentation of human perception by supplying information not ordinarily detectable by human senses) around a user with superimposed computer graphics projected onto the walls or onto a head-mounted display. In another example (referred to as tele-presence), a multitude of stationary cameras mounted at a remote environment are used to acquire both photometric and depth information. A virtual environment is then constructed in real time and redisplayed in accordance with the local participant's head position and orientation. This allows local users to interact with other remote individuals as if they were actually within the same space.

The evolution of multimedia applications can be traced through three major stages.

First, even prior to the deployment of delivery-network infrastructure, stand-alone applications (e.g., video arcade games) and CD-ROM-based applications had successfully integrated multiple media, mostly in the form of games, entertainment, and educational materials.

Next, high expectations of technological breakthroughs to make available lower-cost delivery bandwidth (as needed for sophisticated multimedia applications) created a tremendous excitement in the area of multimedia. The potential for the convergence of multiple services (e.g., TV, movie, and telephone) had stirred up the marketplace. Almost every day, newspaper headlines announced new field trials and potential mergers of corporations.

The focus in multimedia shifted to the creation of large-scale video servers and delivery infrastructure that would be capable of delivering thousands of simultaneous high-quality video streams to homes and businesses. However, the economics of the marketplace has run counter to these high expectations. For example, in movie-on-demand applications, the cost of storage of a large video library and the cost of delivery bandwidth for a two-hour video per customer were found to be prohibitively expensive in comparison with traditional movie rentals.

Categorization of Multimedia

Interactivity relates to communication between the multimedia system and its user; i.e. it requires input from its audience. Interactive media may also be accessed in various sequences by the user, whereas non-interactive multimedia tends to be linear in sequence and involve a ‘passive’ audience (e.g. watching a film is generally a passive occupation and it is shown as a linear medium).

Multimedia may be broadly divided into two categories

Ø Non Interactive multimedia (linear)

Ø Interactive multimedia (non-linear)

Non Interactive (Linear)

Linear active content progresses without any navigation control for the viewer such as a cinema presentation.

Interactive Multimedia (Non-linear)

Non-linear content offers user interactivity to control progress as used with a computer game or used in self-paced computer based training. Non-linear content is also known as hypermedia content. Multimedia presentations can be live or recorded. A recorded presentation may allow interactivity via a navigation system. A live multimedia presentation may allow interactivity via an interaction with the presenter or performer. Some of the common features of interactive multimedia are:

l Multimedia application that accepts input from the users (mouse/keyboard) and performs some action in response

l Allows you to choose the material you want to view, define the order in which it is presented, and obtain feedback on your actions

l Interactive multimedia allows the user to control what and when the elements are delivered (Vaughan, 2001). With the rapid changes in the field of technology, the interactive multimedia has become increasingly popular in education, business, entertainment, and public places. Now multimedia, which has the capability of incorporating various media from text to graphics and from video to sound, is a new way to present information.

Multimedia Objects

A multimedia title begins as notes and sketches that form the foundation of your work. As your work progresses, those notes and sketches evolve into the text and graphics that provide the underlying structure and content of your title.

Text carries the story line and communicates key ideas, while text formatting conveys the contents hierarchy and structure. Text can even link ideas by jumping to other topics when you click on it.

Graphics establish the design of your title-setting your audiences expectations about where to find different types of information in the same way that a magazine or book design does. Graphical elements, such as buttons and icons, help your audience navigate through a title. Graphics also illustrate your content.

Together text and graphics define the look and feel-the interface-of your title and how your audience interacts with it. And these two effects often provide the main content.

The multimedia applications consists of the following objects:

Media types	Common file formats	Description
Text	.TXT .RTF .DOC	Text often shapes the content of a multimedia title, delivering key information and helping people navigate among topics. As a rule, keep text brief and select a font that is easy to read onscreen.
Graphics	.DIB .BMP .TIF .WMF	Graphics shape the design of your title, adding visual appeal and expressing concepts that text alone cannot easily communicate.You can scan graphics or create them on a computer, then save them in the file format you need.
Sound	.WAV .MID	Sound complements your titles with music, sound effects, and voiceovers that create a mood, add emphasis, communicate ideas, or signal interactivity.
Video	.AVI .DVI	Full-motion video offers a level of authenticity similar to television or movies. With video, you can show tasks and events that words and graphics are inadequate to explain. And video quickly and effectively reaches a busy audience.
Animation	.FLC .FLI .MMM	Animation enhances a project by activating graphics - charts that grow, mechanical objects that function- to illustrate your point. You can also use animated effects, such as text or logos flying onto the screen.