Transcript Multimedia – An Introduction Lecture-1

Chapter One
Multimedia
Introduction
Dr. Abbas Fadhil Mohammed
Ali AL-Juboori
[email protected]
2011
All rights reserved
Learning to make digital multimedia on a computer is a bit
like learning a language.
Not a computer language like Visual Basic or C++ but
languages like English or German.
This is because multimedia is more about communication
between human beings than about technology.
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Multimedia Definition
We define digital multimedia as any combination of text,
graphics (still and animated), sound, and motion video
delivered to you by a computer. The computer is an
intrinsic part of multimedia. All these elements text,
graphics, sound, and video are either computer generated,
or transmitted through a computer.
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The word multimedia is a combination derived from
multiple and media. The word medium (the singular of
media) means a transmission channel. For example, sound is
transmitted through the medium of air, or electricity is
transmitted through the medium of wires. Similarly, poetry
could be considered a medium for transmitting our thoughts.
Or for that matter, a painting is a medium for conveying
what we observe. Similarly, a Hollywood director uses the
medium of movies to tell a story. Multimedia is also a
medium .
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The most important difference between traditional
multiple media such as radio and television and digital
multimedia is the notion of interactivity. The power of
computers allows users to interact with the programs.
Since interactivity is such a powerful concept, many
experts in the
field of multimedia consider interactivity to be an
integral part of multimedia. We will also follow this
convention. Thus, whenever we say the word multimedia,
you should understand that we are referring to digital,
interactive multimedia.
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ELEMENTS OF MULTIMEDIA
The first element of multimedia we consider is audio. The
word audio is slightly different from sound. Audio
consists of the sounds we can hear. This may seem
contradictory, but it is well known that humans do not
hear all possible sounds. For example, the sound emitted
by the dog-whistle is recognized by dogs but not by
humans. Audio is one of the most appealing elements of
any successful multimedia presentation.
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The audio that appears in a multimedia presentation is of
two types. It is either computer generated, or recorded
and converted into a digital format.
Perhaps the most important element of multimedia is the
graphic element. Multimedia presentations are
predominantly graphics based. Information
communicated through pictures is easier to understand
and retain.
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Graphic elements in a multimedia system could be still
pictures (like photographs) converted to digital format
with the help of scanners, or generated on the computer.
They may be flat (or two-dimensional), such as
photographs and paintings, or they may appear solid (or
three-dimensional), like sculptures and objects around us.
They may be either static graphic elements or animated.
Further, animations may be two-dimensional, as in old
cartoon films, or three-dimensional.
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Computer-generated text is another element of
multimedia. A few words appearing in a predominantly
graphic multimedia system can have a powerful effect. On
the Internet, text is used much more than on stand-alone
multimedia products, so it takes on an added importance.
Also, text and art can be mixed together in interesting
ways to reinforce the message being transmitted. Text can
also be animated in interesting ways.
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Finally, we mention that video is another element of
multimedia. Obviously, video and audio are closely
related, and together they are the most effective means of
communication that can be a part of the multimedia
system.
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MASS MEDIA VERSUS MULTIMEDIA
DIGITAL AND ANALOG DATA
the computer is an intrinsic part of multimedia. Thus all the
elements of multimedia have to be in digital format. In
contrast, other multiple media such as TV programs and films
are analog in nature. It is important to understand the
difference between the two formats.
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The difference between discrete and continuous.
Consider a line segment
connecting two points. There are an infinite number of
points on any line segment. However, when we wish to
write a program to draw a line segment on the screen
connecting two points, we will not be able to draw an
infinite number of points. This is because the number of
pixels on the screen is finite, and only a finite number of
pixels have to be colored black (on a white screen) to
draw a line segment.
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In other words, we can say that the line segment (as
defined in geometry books) is continuous and the line
made on the computer screen is discrete.
However, since the pixels on the screen are very close to
each other, our eyes cannot tell the difference, and we
perceive a continuous line.
we can say that analog is continuous data, and digital is
discrete. The plants and trees that we see around us are
continuous, but their digital pictures are forced to be
discrete.
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Nevertheless, we have seen that if we include enough data
in our digital representation, our eyes cannot tell the
difference. One advantage of working with digitally stored
media is the comparative ease of editing media files. This is
the primary reason why even analog media studios employ
computers in their work. For example, the 2-D and 3-D
animations that you see these days on television
and in movies are almost all done by using computers.
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One consequence of requiring all multimedia elements to be in
a digital format is that we need special hardware and software
to convert from analog to digital format. For example, we
may shoot a video to incorporate in our multimedia project,
but we need some special software and hardware to convert
it into a digital format, aside from the software to edit it.
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Moreover, multimedia files usually take up a lot of space
on the disk, so we usually use different techniques to
reduce the file size of (or compress) the data. We may also
need to find special programs to view or play the files.
For example, to compress music files using a technique
called MP3 compression, we use an MP3 encoder. To play
the music files, we need (aside from the usual multimedia
computer)
software that can play the music in this format an MP3
Player.
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Multimedia is Multidisciplinary
Computer
networks,
operating system
Image, audio,
speech processing
Multimedia
computing
Human computer
interaction
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Computer vision,
pattern recognition
Computer
graphics
Multimedia- Applications
Multimedia plays major role in following areas
 Instruction
 Business
 Advertisements
 Training materials
 Presentations
 Customer support services
 Entertainment
 Interactive Games
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Multimedia- Applications
 Enabling Technology
 Accessibility to web based materials
 Teaching-learning disabled children & adults
 Fine Arts & Humanities
 Museum tours
 Art exhibitions
 Presentations of literature
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Software Tools
 Categories
 Music Sequencing and Notation
 CackWalk, Cubase,
Macromedia Sound Edit, etc
 Digital Audio
 Cool Edit, Sound Forge, Pro Tools, etc
 Graphics and Image Editing
 Adobe Illustrator, Adobe Photoshop, Macromedia Fireworks, etc
 Video Editing
 Adobe Premiere, Windows Movie Maker, iMovie, etc
 Animation
 3D Studio Max, Maya, etc
 Multimedia Authoring
 Macromedia Flash, Macromedia Director, etc
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Multimedia- Applications
In Medicine
Source:
Cardiac Imaging,
YALE centre for
advanced cardiac
imaging
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Multimedia- Applications
In training
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Multimedia- Applications
Public awareness
campaign
Source
Interactive Multimedia Project
Department of food science&
nutrition, Colorado State Univ
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Reference Book
 Introduction to Multimedia Systems, by Gaurav Bhatnagar ,
Shikha Mehta , Sugata Mitra .2002
 Multimedia Cartography, by William Cartwright
Michael P. Peterson , Georg Gartner . 2007
 MULTIMEDIA IMAGE andVIDEO PROCESSING,
by Ling Guan , Sun-Yuan Kung ,Jan Larsen.2009
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