15-2 ELEMENTS OF MULTIMEDIA
If we break the word multimedia into its component parts ,we get multi -meaning
more than one ,and media-meaning form of communication.Those types of media
. Audio Sound
. Static Graphics Images
. Full-Motion Video
Let's look at each of these components in more detail.
Whether or not they have used a computer ,most people are familiar with text. Text is the basis for word processing programs and is still the fundamental information used in many multimedia programs.
In fact ,many multimedia applications are based on the conversion of a book
to a computerized form.This conversion gives the user immediate access to the
text and lets him or her display pop-up windows , which give definitions of
certain words.Multimedia applications also enable the user to instantly display
information related to a certain topic that is being viewed.Most powerfully
,the computerized form of a book allows the user to look up information quickly
(without referring to the index or table of contents).
The Windows operating environment gives the user an almost infinite range of
expressing text.As a multimedia programmer ,you can choose what font to display
text in ,how big (or small) it should be ,and what color it should be displayed
in .By displaying text in more than one format ,the message a multimedia application
is trying to portray can be made more understandable.
One type of application ,which many people use every day ,is the Windows Help
Engine.This application is a text-based information viewer that makes accessing
information related to a certain topic easy.
2. Audio Sound
The integration of audio sound into a multimedia application can provide the user with information not possible through any other method of communication .Some types of information can't be conveyed effectively without using sound.It is nearly impossible ,for example ,to provide an accurate textual description of the bear of a heart or the sound of the ocean.
Audio sound can also reinforce the user's understanding of information presented
in another type of media.For example ,a narration might describe what is being
seen in an animation clip.This can enhance the understanding of what the application
is all about and lead to better comprehension.Experts in learning have found
that presenting information using more than one sense aids in later retention
of the information.Most importantly ,it can also make the information more interesting
to the user.
Audio sound is available in several different formats.Today ,maybe the most
common type of audio is red book audio.This is the standard specification used
to refer to consumer audio compact discs.It is an international standard and
is officially known as IEC 908.This specification is called red book audio because
of the color of the cover of the publication that describes its formats.red
book audio sound can also be used in multimedia applications ,and it forms the
basis of the highest quality sound available.
Another audio sound format is the Windows wave file ,which can be played only
on PCs running the Windows operating environment.A wave file contains the actual
digital data used to play back the sound as well as a header that provides additional
information about the resolution and playback rate.Wave files can store any
type of sound that can be recorded by a microphone.
The final type of audio sound that may be used is known as the Musical Instrument
Digital Interface ,or MIDI for short.The MIDI format is actually a specification
invented by musical instrument manufacturers.Rather than being a digitized form
of the sound ,the MIDI specification is actually a set of messages that describes
what musical note is being played.The MIDI specification cannot store anything
except in the form of musical notes.MIDI music can be created with a sequencer.
3. Static Graphics lmages
When you imagine graphics images you probably think of "still" images-that is ,images such as those in a photograph or drawing.There is no movement in these types of picture.Static graphics images are an important part of multimedia because humans are visually oriented.As the old Chinese proverb goes ,"A picture is worth a thousand words."Windows is also a visual environment.This makes displaying graphics images easier than it would be in a DOS-based environment.
Static graphics images have a number of formats and can be created in a number
of different ways.Just as you can see an unlimited number of photographs or
pictures ,the types of static graphics images that you can include in a multimedia
application are almost unlimited.
Animation refers to moving graphics images.The movement of somebody giving CPR makes it much easier to learn cardiopulmonary resuscitation ,rather than just viewing a static picture.Just as a static graphics image is a powerful form of communication ,such is the case with animation.Animation is especially useful for illustrating concepts that involve movement.
Such concepts as playing a guitar or hitting a golf ball are difficult to illustrate
using a single photograph ,or even a series of photographs ,and even more difficult
to explain using text.Animation makes it easier to portray these aspects of
your multimedia application.
5. Full-Motion Video
Full-motion video ,such as the images portrayed in a television ,can add even more to a multimedia application.Although full-motion video may sound like an ideal way to add a powerful message to a multimedia application ,it is nowhere near the quality you would expect after watching television.Full-motion video is still in its beginning stages on PCs ,and it is limited in resolution and size.Even with advanced methods of data compression ,full-motion video can suck up hard disk space faster than water falls when poured out of a bucket.
Right now ,there are two major methods of incorporating full-motion video into
a multimedia application: Microsoft Video for Windows ,and Quick Time for Windows
from Apple Computers.Both products come with tools for getting the video from
an external input (a videocassette recorder or a video camera) and storing it
on your hard disk drive.
6. All of the Above
You can see that multimedia is by on means just one of the preceding technologies.Because of what hardware can and cannot do ,it is often a trade-off between a certain number of static graphics images ,audio sound ,full-motion video and text.As you may guess ,textual information takes the least amount of space to store.
Even if a multimedia machine had unlimited resources ,you would still want
to add a combination of these multimedia technologies.For example ,although
a picture is worth a thousand words ,it would be difficult to portray the work
of William Shakespeare through pictures only.The same goes for audio sound.You
could record the sound of church bells and a narration of the Bible ,but at
times you would rather have the Bible in textual format , which would allow
you to search for certain keywords .