نظام الوسائط المتعددة

1. Multimedia Systems
‫المتعددة‬ ‫الوسائط‬ ‫نظم‬
‫د‬
.
‫بسام‬ ‫مصعب‬

2. • Definition
• Introduction to Multimedia
• Media classification
• Representation of Media
• Main Properties of Multimedia Systems
• Definition of Multimedia Systems
• Multimedia-Related Technologies
• Key properties of a MM system
• Where to Use MM
• MM Hardware & Software

3. • 1-Mult: Latin word "Multus" which mean
"numerous, many", a lot of
• 2-Media: plural form of medium. The word
medium according to dictionary has two
meanings:
1- An intervening substance through which
something is transmitted or carried on
2- A means of mass communication such as
newspaper, magazine, or television

4. 1- Definition
Multimedia--the combination of text, animated
graphics, video, and sound--presents information in a
way that is more interesting and easier to grasp than
text alone.
It has been used for education at all levels, job
training, and games and by the entertainment
industry.
It is becoming more readily available as the price of
personal computers and their accessories declines.
Multimedia as a human-computer interface was
made possible some half-dozen years ago by the rise
of affordable digital technology.

5. Previously, multimedia effects were produced
by computer-controlled analog devices, like
videocassette recorders, projectors, and tape
recorders.
Digital technology's exponential decline in
price and increase in capacity has enabled it to
overtake analog technology.
The Internet is the breeding ground for
multimedia ideas and the delivery vehicle of
multimedia objects to a huge audience.

6. 2- Multimedia--An introduction
Nowadays, multimedia generally indicates a rich
sensory interface between humans and computers
or computer-like devices--an interface that in most
cases gives the user control over the pace and
sequence of the information.
• We all know multimedia when we see and hear it,
yet its precise boundaries elude us. For example,
movies on demand , in which a viewer can select
from a large library of videos and then play, stop, or
reposition the tape or change the speed is generally
considered multimedia.

7. • However, watching the movie on a TV set
attached to a videocassette recorder (VCR)
with the same abilities to manipulate the play
is not considered multimedia. Unfortunately,
we have yet to find a definition that satisfies
all experts.
• Recent multimedia conferences, provide a
good start for identifying the components of
multimedia

8. 3- Media classification
• With computer processing:
– Medium –a means of distribution and
presentation of information: text, graphics,
speech, music……
• Media can be classified with different criteria. We
can classify media according to:
– Perception,
– Representation,
– Presentation,
– Storage,
– Transmission,
– Information exchange

9. Perception medium
Perception media help the humans to sense
their environment; perception mostly occurs
through seeing or hearing the information.
• For the perception through seeing the visual
media such as text, image and video are used.
• For the perception of information through
hearing, auditory media such as music, noise
and speech are relevant.

10. The Representation Medium
Representation media are characterized by internal computer representations
of information. The central question is:
* How is computer information coded? There are various formats used to
represent media information in a computer, For example:
• Text is coded in ASCII code (America Standard Code for Information
Interchange) or EBCDIC (Extended Binary Coded Decimal Interchange Code)
is an 8-bit character encoding used on IBM mainframe.
• Graphics are coded according to CEPT or CAPTAIN videotext standard
(Character And Pattern Telephone Access Information Network , or the
graphics standard GKS(Graphic Kernel System) .
• Audio stream can be represented using a simple PCM (Pulse Code
Modulation) method.
• Image can be coded as a fax or in JPEG format.
• Video sequences can be coded in different TV standard formats (e.g. PAL,
SECAM, NTSC) and can be stored in MPEG format (Motion Picture Experts
Group) standard for video and associated audio

11. The Presentation Medium
• Presentation media refer to tools and devices for the input
and output of information. The central question is: Through
which medium is information delivered by the computer, or
introduced into the computer? The media to deliver
information by computer (output media) includes paper,
screen, speaker, whereas the input media are keyboard,
mouse, camera, and microphone.
The Storage Medium
Storage media refer to a data carrier which enables storage of
information. The central question is: Where will the
information be stored? Examples of storage media are Floppy
disk, Hard disk, CD-ROM, Magnetic Tapes, Removable Disk,
Microfilm and even paper.

12. The Transmission Medium
• The transmission medium characterises different information
carriers that enable continuous data transmission. The central
question is: Over what will the information be transmitted? The
answer is that information is transmitted over networks, which
use wire and cable transmission such as coaxial and fiber optics,
as well as free air space transmission for wireless
transmissions( Radio tower ,satellite.
The Information Exchange Medium
The information exchange medium includes all information
carriers for transmissions, i.e. all storage and transmission media.
The central question is: Which information carrier will be used
for information exchange between different places? Information
can flow through intermediate storage media, where storage
media is transported outside through computer networks to the
destination, through direct transmission using computer
networks, or through combined usage of storage and
transmission media ( e.g. e-mail).

13. 4- Representation of Media
• The media is characterised as
information to be processed in computer
systems. Each medium defines the
following:
1- Representation Values
2- Representation Space
The user will perceive the content through
these representations

14. • 1- Representation Values
Representation values are the actual information
representation of the media. A sentence can be represented
by text, which is a sequence of characters, or by speech,
which is in a waveform. Representation values can be
considered either as a continuum or a sequence of discrete
values.
• 2- Representation Space
Paper or computer monitors are examples of a visual
presentation spaces. Each representation space consists of
one or more representation dimensions. A computer screen
has 2 spatial dimensions; holography and stereophony require
an additional spatial dimension. Time can occur in each
representation space as an additional dimension, as it has
central meaning to multimedia systems.

15. Representation Dimensions
• Media can be divided into two types with respect to time in their
representation space:
• Time-independent (discrete)
• Some media such as text , pictures and graphics, are time-independent.
Information in these media consist exclusively of a sequence of
individual elements or of a continuum without a time
component.(indeed, they may be displayed according to a wide variety
of timing and still remain meaningful).
• Time-dependent (continuous)
Other media, such as sound and motion video(means pure moving
images), change over time. Information is expressed not only on the
individual value but also the time of its occurrence (requires a
continuous playout as a time passes).
• The meaning depend on the level of the relative change of the discrete
values or of the continuum. Representation caused by tactile or
temperature sensors with threshold detectors are also time-dependent
and falls under this category. Processing these media is time critical
because the validity of the data depends on a time condition.

16. As a conclusion the Classification of
Media as follows:
– Perception Medium
• How do humans perceive information in a computer?
– Through seeing - text, images, video
– Through hearing - music, noise, speech
– Representation Medium
• How is the computer information encoded?
– Using formats for representing and information
– ASCII(text), JPEG(image), MPEG(video)
– Presentation Medium
• Through which medium is information delivered by
the computer or introduced into the computer?
– Via I/O tools and devices
– paper, screen, speakers (output media)
– keyboard, mouse, camera, microphone (input media)

17. Classification of Media (cont.)
– Storage Medium
– Where will the information be stored?
– Storage media - floppy disk, hard disk, tape, CD-ROM etc.
– Transmission Medium
– Over what medium will the information be transmitted?
– Using information carriers that enable continuous data transmission
- networks
– wire, coaxial cable, fiber optics
– Information Exchange Medium
– Which information carrier will be used for information exchange
between different places?
– Direct transmission using computer networks
– Combined use of storage and transmission media (e.g. electronic
mail).

18. Media Concepts
• Each medium defines
• Representation values - determine the information
representation of different media
– Continuous representation values (e.g. electro-magnetic
waves)
– Discrete representation values(e.g. text characters in
digital form)
• Representation space determines the surrounding
where the media are presented.
– Visual representation space (e.g. paper, screen)
– Acoustic representation space (e.g. stereo)

19. • Representation dimensions of a
representation space are:
– Spatial dimensions:
• two dimensional (2D graphics)
• three dimensional (holography)
– Temporal dimensions:
• Time independent (document) - Discrete media
– Information consists of a sequence of individual elements
without a time component.
• Time dependent (movie) - Continuous media
– Information is expressed not only by its individual value
but also by its time of occurrence.

20. Multimedia Systems
• Qualitative and quantitative evaluation of
multimedia systems
– Combination of media
• continuous and discrete.
– Levels of media-independence
• some media types (audio/video) may be tightly
coupled, others may not.
– Computer supported integration
• timing, spatial and semantic synchronization
– Communication capability

21. 5- Main Properties of Multimedia Systems
• From our understanding of the different media elements, we
related to multimedia systems in a qualitative manner based
on the important properties below:
• Combination of Media
A multimedia system combines both continuous and discrete
media. A simple text processing program with incorporated
images should not be considered as a multimedia application.
• Independence
An important aspect of different media is their level of
independence from each other. In general, there is a request
for independence of different media, but multimedia may
require several levels of independence.

22. • Computer-supported Integration
The media-independence prerequisite provides the
possibility of combining media in arbitrary forms.
Computers are ideal tool for this purpose. The
system should be capable of computer-controlled
media processing. An integrated multimedia system
is necessary to provide functionality that support all
the different forms of media.
• Communication Systems
Communication has become essential in multimedia
systems. Today's computers are interconnected and
the multimedia functions should be available
beyond the processing of a single computer.

23. 6- Definition of Multimedia Systems
Based on the details above, the following
definition can be used to describe multimedia
systems: “A multimedia system is characterized by
computer-controlled, integrated
production ,manipulation, presentation, storage
and communication of independent information,
which is encoded at least through a continuous
(time-dependent) and a discrete (time
independent)medium.”
A few examples of multimedia systems are: Video
on demand, Electronic book, Interactive cinema,
Internet Bookshop, and Games. so Multimedia
systems are computer-based systems that
support the delivery of multimedia content.

24. 7- Multimedia-Related Technologies
• Multimedia systems is the integration of many components of
different technologies. The development of multimedia
technology is related to the evolution of the following
technologies:
• Computer Technology
With faster processing power, larger memory and storage
capacities, the multimedia capabilities of the computer has
increased significantly in the last decade. This has enabled the
development of multimedia intensive applications in many
areas.
• Telecommunications
Digital networks with higher bandwidths increased the
development of distributed multimedia applications, especially
through the internet.
• Consumer Electronics
Improvements in devices such as display units and optical
storage contributed to new and better multimedia facilities. In
addition, mass production reduced the prices significantly for

25. • Entertainment and Broadcasting
Professional audio and video production has
significantly improved the technical
capabilities and multimedia contents. These
are adapted to multimedia systems for
better quality products.
• Publishing
Many large publishing houses already offer
their publications in electronic form. More
and more multimedia information can be
offered.

26. 8-Key properties of a MM system:
• They must be computer control controlled thus, a
computer must be involved at least in the
presentation to the user
• They are integrated , that is they use .Minimum
number of different devices example :single
computer screen is used to display all type of visual
information
• They must be support media independence ‫اسمع‬
‫موسيقى‬
‫غير‬
‫النص‬
‫غير‬
‫الفلم‬
• They need to handle discrete and continuous media

27. 9-Application Areas Where to Use MM:
• Residential Services
• video-on-demand
• video phone/conferencing systems
• multimedia home shopping (MM catalogs, product
demos and presentation)
• self-paced education
• Business Services
• Corporate training
• Desktop MM conferencing, MM e-mail

28. • Education
• Distance education - MM repository of class videos
• Access to digital MM libraries over high speed
networks
• Science and Technology
• computational visualization and prototyping
• astronomy, environmental science
• Medicine
• Diagnosis and treatment - e.g. MM databases that
provide support for queries on scanned images, X-
rays, assessments, response etc.

29. • MM in Business:
Presentation, Training, Marketing, Advertising, DB, Catalog,
Network communication voice mail, Video conference will be
soon provided on many local and wide area network.
• MM is School :
connect every Class room ,Library ,Clinic and Hospital
• MM at Home :
TV set or monitor with built in interactive user input or use
computer with CD-ROM device , or set top players(Kodak
photo CD player, Philips CD-1, or Panasonic 3DO Player
• MM in public place :
Hotels, Train station, shopping malls,….to provide information
and help.

30. 10 - MM Hardware & Software:
• Digital media device: Keyboard, Scanner, Display driver.
• Analog media device : We can divided into 3 parts :
– Source produce analog signal Video, Camera, microphone
– Sink consumer convert of analog signal : speaker, video
display
– Filter :convert form One analog to another audio mixer,
video overlay device.
• General purpose devices Ex:
• 1- Sorting device CD-ROM, Magnatic disk …
2-network interface
• Interaction ‫تفاعل‬ devices : Mouse, Joystick, electronics pens
,Keyboard