Transcript Chapter 1

Chapter 1
Introduction
Multimedia Systems
Key Points
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Digital multimedia is any combination of two
or more media, represented in a digital form,
sufficiently well integrated to be presented via a
single interface, or manipulated by a single
computer program.
Multimedia can be delivered offline (e.g. on CDROM) or online (e.g. on the World Wide Web).
Multimedia has a wide range of application, from
entertainment to education and business.
Key Points
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There are many precedents for the integration of
media, but the addition of interactivity is a
novel contribution of digital multimedia.
Access to multimedia is not universal.
The issues raised by censorship (監察) have a
very long history and have not been
satisfactorily resolved.
The challenge and opportunity of multimedia
remains.
Introduction
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What is Medium (pl. media)
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Something in a middle position.
A substance regarded as the means of
transmission of a force or effect.
An intervening substance though which
something is transmitted or carried on (介
質).
A means of mass communication such as
newspaper,magazine or television (傳媒).
Something gives our senses access to
further form of information.
Introduction
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What is Multimedia (Multiple-Media)
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A combination of text, graphics, images,
video and audio to enrich its content and
enhance communication.
Introduction
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What is digital Multimedia
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Any combination of two or more media,
represented in a digital form, well integrated to be
presented via a single interface, or manipulated by
a single computer program.
Examples
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Forensic (法院的) multimedia
Entertainment and education: Video game
Digital Encyclopedia Britannica (大英百科)
CD titles
Sale presentation and promotions
Scientific visualization.
Introduction
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Delivery of Multimedia
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Multimedia can be delivered
Offline (e.g. on CD-ROM)
 Online (e.g. on the World Wide Web).
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Online delivery provides live multimedia
content such as video conferencing and
broadcast multimedia (compression &
databases).
TV, movies: linear and noninteractive
Multimedia Production
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Making of multimedia requires software
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not only for preparation of individual media
elements
but for their integration into a finished
production
Authoring systems
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programs that allow a designer to
assemble different media in space and
time, and add interactive behavior to them.
Storyboards
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A means of making and communicating
multimedia design
Sequence of still pictures showing
composition of shots at key points in
production
Non-linearity added to storyboard
Terminologies
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Multimedia production and multimedia
applications
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Production: present material in a fixed way
Application: generate multimedia
dynamically
Different sorts of perception such as
reading text, looking at pictures,
listening to sound.
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Cognitive scientists call these different
sorts of perception modalities.
Interactivity
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Control the content and flow of information
Providing choices in computer program is
much easier than providing choices via
hardware such as VCR
User Interfaces
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Fig. 1.1, dialog box
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Text entry areas, pop-up menus, buttons
Disadvantages
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Users who are not already familiar with the interface
convention might find it harder to use than a specially
designed simpler one (Fig. 1.2)
Everything looks the same
Innovative interface
User Interfaces (2)
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Interface elements that have become most
familiar to users
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Menu commands with keyboard shortcuts
Playback controls
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Mimic the operation on VCR and de facto standard
icons (Fig. 1.2)
Additional control
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Strip with a marker that can be pulled through it
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A new interface convention
Social and ethical (倫理) considerations
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Access to multimedia: Consumption
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Depends
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is not universal
Availability of computers
Reliable infrastructure:
power supplies, ubiquitous (到處存在)
telecommunications
Telecommunication charge rate
Computer skill
Physical disability or learning difficulties
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on access to appropriate hardware
on possession of necessary skills
Voice synthesizers
Braille (點字) keyboards
Difficulty in distinguishing between certain colors
Security
Social awareness
Access to Multimedia: Production
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Access right
Write access
 Read access
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Inexpensive tools for constructing Web
sites
Means of production and distribution of
traditional media is tightly restricted.
Recorder music: multinational corporations
 Film: enormous cost
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Control of Multimedia
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Most popular sites on WWW are home sites of
ISP
Web portals
 Search engines
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One-to-many
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Broadcasting, publication and marketing
Few-to-few: WWW
Control of Content
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Control over what people may read, see, hear or do
Rapid growth of Internet
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Mechanisms exist for controlling publication,
exhibition, performance and so
Platform for Internet Content Selection (PICS)
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Censorship (檢查)
Restricts reception, not distribution
Allow user to prevent unacceptable material reaching them
Labels are associated with each Web page.
Undesirable material is rejected by screening software
A standard format for content labelling
Recreational Software Advisory Council (RSAC)
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Crude measures of violence, sex, nudity and language
Control of Content
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PICS allows labels to be attached by
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Page’s author
Third party
You have to trust labelling service
PICS label for searching program
A New Medium
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Very brief history of multimedia
Web pages
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After several years, can support elaborate
layout, typography, animation, video, sound,
and interactivity
SETI
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Search for Extraterrestrial Intelligence
Internet: a collection of connected computers