MSD slides by HASSAN DAR

1. CGMB324:
MULTIMEDIA SYSTEM
DESIGN
Chapter 2: Issues In Multimedia Authoring &
Design

2. Objectives
Upon completing this chapter, you should be
able to:
 Understand the theory and concept of multimedia
authoring
 Differentiate between the Multimedia Authoring
Metaphors
 Address the Content Design Issues
 Understand the Visual Design Issues
 Be aware of the Technical Design Issues
 Foresee the Fundamental Design issues

3. Multimedia Authoring

4. Multimedia Authoring
 MultimediaAuthoring the process of
creating multimedia application.
 During authoring, you might need to
organize or edit the elements of your
multimedia project, create user interface
and designing interactivity.
 This can be achieved through the use of
authoring programs / tools.

5. Why would anyone want to use an
authoring program?
 Why it is more efficient and effective to use an
authoring system:
 Simplify the inherently complex task of
creating interactive multimedia.
 Reduce the time needed to develop the
application
 Increase productivity
 Reusability of the content e.g. graphics,
animations, audio, video clips.

6. Authoring Tools
 Multimedia authoring tools are the central
integrative tools use to combine all the media
resources within a structured framework.
 Important to select an authoring tool that best
suits project needs.
 There are a number of factors that will narrow the
range of choice :
 the hardware available for development and
delivery
 the nature of the multimedia project
 price
 the market penetration of the tool.

7. Authoring & The Metaphor Used
 Authoringmetaphor== autho ring paradig m  for
easier understanding of the methodology
employed to create multimedia applications.
a) Scripting-language metaphor
b) Slide show metaphor
c) Hierarchical metaphor
d) Iconic/Flow-control metaphor
e) Frames metaphor
f) Card/Scripting metaphor
g) Cast/Score metaphor

8. a) Scripting Language Metaphor
 uses a special language to enable interactivity (button,
mouse, etc), and to allow conditionals, jumps, loops,
functions/macros
 e.g., OpenScript in Toolbook by Asymetrix
-- load an MPEG file
extFileName of MediaPlayer “theMpegPath” =
“c:windowsmediamedia.mpg”;
-- play
extPlayCount of MediaPlayer “theMpegPath” =
1;
--if want to start and end at specific
frames
extSelectionStart of MediaPlayer
“theMpegPath” = 103;
Example of OpenScript

9. b) Slide Show Metaphor
 by default a linear presentation
 However, tools exist to perform jumps/hyperlink –
seldom used
 e.g., PowerPoint, ImageQ

10. c) Hierarchical Metaphor
 User-controllable elements are
organized into a tree structure.
 Often used in menu-driven applications

11. d) Iconic/Flow-control Metaphor
 graphical icons are available in a toolbox
 Authoring proceeds by creating flow chart with icons
attached.
 e.g., Authorware by Macromedia

12. e) Frames metaphor
 As in iconic/flow-
control metaphor,
but uses C language
as the programming
language
 rather than
represent the actual
flow of the program,
links between icons
are more conceptual

13. f) Card/Scripting Metaphor
 index-card structure, good for hypertext/hypermedia
 e.g., SuperCard, HyperCard by Apple

14. g) Cast/Score/Scripting Metaphor
 with cast members,
music scores, and
scripting language;
 many synchronous
horizontal "tracks"
simultaneously
shown in vertical
columns;
 e.g., Director by
Macromedia (Uses
Lingo = scripting
language)

15. Content Design Issues

16. Content Design Issues
 "In multimedia, there are five ways to format
and deliver your message.
 You can write it, illustrate it, wiggle it, hear it,
and interact with it." -- D.E. Wolfgram (author
of, ‘Creating Multimedia Presentations’)

17. Scripting
A) Scripting (writing)
Rules forgood writing:
1. Understand your audience and correctly
address them.
2. Keep your writing as simple as possible.
-- e.g., write out the full message(s) first, then
shorten it.
3. Make sure technologies are used to
complement each other.

18. Graphics
B) Graphics (illustrating)
 Make use of pictures to effectively deliver your
messages. – as in the old adage, "A picture is
worth a thousand words."
 Create your own material (draw, scan,
PhotoCD, ...), or keep "copy files" of art works.
 Color Themes -- be consistent with the
contents
 pastels (pale or light colors)
 earth tones
 metallic colors

19. Animation
C) Animation (wiggling)
Types of Animation
 Character Animation -- humanize an object
e.g., a toothbrush, a car, a coke bottle, etc.

20. Animation
 Factors in choosing a character
 Emotion -- Is it happy, sad, funny,
sloppy, ...?
 Movement -- Is it fast, slow, bumpy, ...?
 Visual style -- Is its color/texture
consistent with the rest?
 Copyright -- "Don't use Mickey Mouse
before checking with Disney."
 Adequacy -- e.g., Does it provide various
poses? (can't make a broomstick sit!)

21. Animation (Effects & Transitions)
 Highlights and Sparkles
 e.g., to pop a word in/out of the screen, to sparkle a
logo --> to draw attention
 Moving Text
 e.g., put up one character at a time like a typewriter
OR "pulsing" -- the word grows/shrinks (or changes
color) a few times – the typewriter effect can be used
to create a suspense atmosphere as well of slowly
revealed info.
 Note: Do not slowly move entire line of text, they are
not easily readable. Instead, for example, slide the
bullets in and out.

22. Video
 Video -- live video or digitized video
+Advantages
 more powerful than still images
 often easier to obtain than graphics animation
- Disadvantages
 takes a lot of disk space
 sometimes needs special hardware (depends
on compression used) but more often,
requires a codec to be installed to play the
particular video

23. Audio
D) Audio (hearing)
Types of audio in multimedia applications
 Music -- sets the mood of the presentation,
enhances the emotion, illustrates points
 Sound effects -- to make specific points, e.g.,
squeaky doors, explosions, wind, ...
 Narration -- most direct message, often
effective

24. Interactivity
E) Interactivity (interaction)
 Interactive multimedia systems are important
 Studies have shown that people remember
70% of what they interact with (Edgar Dale –
Cone Of Learning)

25. Interactivity
Some Common Types of Interactive Multimedia
Applications:
Menu-driven programs and presentations
Hypermedia
Simulations/Performance-dependent Simulations
e.g., Games -- SimCity, Flight Simulators
Video-conferencing (NetMeeting, etc.)

26. Visual Design Issues

27. Visual Design Issues
 There are a few issues with regard to visual
design that must be considered :
 Themes/Styles
 Graphic Styles
 Animation Styles
 Pace & Running Length
 Basic Layout/User Interface

28. Themes & Styles
1. Themes & Styles -- A multimedia
presentation should have a consistent
theme/style; it should not be disjointed and
cluttered with multiple themes.
The choice of the theme/style depends on
the styles and emotions of your audience.

29. Various themes can be
used for interface
design
Various themes can be
used for interface
design

30. Themes & Styles (Examples)
Cartoon theme
 interesting/entertaining
 must be consistent with the character's personality
 perhaps suitable for an audience of children
Traditional theme
 straightforward marketing pieces
 simple, often informative
 not as interesting

31. Themes & Styles (Examples)
Hi-Tech theme
 contemporary computer art work (morphing, texture
mapping, metal texture, explosions, ...)
 attractive, easy to animate
Technical theme
 include blueprints, 3D models of the product, ... e.g.,
start with a drawing, then transformed into a rendered
image.
 shows adequate technical information
 gives impression of solid design and construction

32. Graphic Styles
2. Graphic Styles
 Some colorschemes (e.g., natural and floral for
outdoor scenes) and art styles (e.g., oil paints,
watercolours, color pencils, pastels) are best
combined with a certain theme/style.
http://www.pibweb.com/review/giveaway/interface.jpg

33. Graphic Styles
Color Principles and Guidelines
 Do not use too many colors!
 Be consistent with the use of color
 Use colors to separate ideas and signal
changes
Fonts
 Size: e.g., Use large fonts (e.g., 18 to 36
points), no more than 6-8 lines per screen –
depends on the application.
 Style: -- e.g., serif vs. sans serif

34. Animation Styles
3.When to Animate ?
"A leaf doesn't flutter if the wind doesn't blow."
Only animate when it has a specific purpose
oris necessary forthe application

35. Using Animation
 Enhance emotional impact
e.g., dove softly flapping its wings --> peace
e.g., air bag explosion + dummy movements
--> car crash.
 Make a point e.g., show insertion of a memory
chip onto the motherboard (much better than a
diagram)

36. Using Animation
 Improve information delivery
e.g., "pulsing" words (in and out of
screen) adds emphasis
 Indicate passage of time
e.g., clock/hourglass --> program still
running
e.g., animated text --> to prompt for
interaction/response

37. Animation Transitions
 Some transitions
 Wipes -- e.g., L-to-R, T-D, B-U, diagonal,
iris round, centree to edge, etc.
 Dissolve -- the current image distorts into
an unrecognizable form before the next
clear image appears, e.g., boxy dissolve,
cross dissolve, etc.
 Fade -- a metaphor for a complete change
of scene
 Cut -- immediate change to next image,
e.g., for making story points using a close-
up

38. Pace & Running Length
4. Pace and Running length
A few guidelines:
 Allow a block of text to be slowly read
twice.
 Transition time should be taken into
account for the total running time

39. Pace & Running Length
Running length (generally)
 self running presentation: 2-3 minutes
 limited interaction: 5-6 minutes
 complete analytical, hands-on demo: <
15 minutes
 with questions, discussions: > 30
minutes
Youshouldimplement built inbreaks forlongpresentations

40. Basic Layout
5. Basic Layout
 make sure that the information delivery path in
the layout is smooth, not irregular or jumpy
 chronological (what naturally comes first,
should be placed first; e.g. 1980 before 1985)
 use headlines/subtitles, additional shapes,
buttons, fonts, backgrounds and textures to
enhance the visual appearance.

42. Technical Design Issues

43. Technical Design
Tech Issues: Technical parameters that affect the
design and delivery of multimedia applications
NormalVideoMode
Video Mode Resolution Max # Colors
CGA 320 x 200 4
EGA 640 x 350 16
VGA 640 x 480 16
or 320 x 200 256

44. Technical Design
HighColorVideo Mode
Video Mode Resolution Max # Colors
SVGA 640 x 480 16.7 million *
SVGA 800 x 600 16.7 million *
SVGA 1,024 x 768 16.7 million *
SVGA 1,152 x 864 16.7 million *
SVGA 1,280 x 1,024 16.7 million *
SVGA 1,600 x 1,200 16.7 million *

45. Note
* The actual number of colors displayed may be
smaller, it depends on the amount of video
memory on the graphics card.
•8-bit color  256 colors
•16-bit color  65,536 colors
•24-bit color  16.7 million colors

46. Technical Design
1. Video Mode & Computer Platform
PC  Macintosh
There are many "portable", "cross-platform" software
and "run-time modules", but many of them lose
quality/performance during the translation.
2. Memory & Disk Space Requirements
Rapid progress in hardware alleviates the problem,
but software is too "greedy", especially the multimedia
ones.

47. Technical Design
3. Delivery
• Live Presentation
• Delivery by diskette
• Small in size, slow to install
• Delivery by CD-ROM/DVD-ROM
• Largercapacity
• Access time of CD-ROM/DVD-ROM drives is
longerthan hard-diskdrives
• Electronic Delivery (Netshow/Streaming-video, etc.)
• depends on baud rate, network connection, and
monthly bill

48. Overall Design Issues

49. Address The Needs
 To ensure success the MM system must
support multimedia applications that address
the diverse needs of users or clients
 Architecture and design of the overall systems
should cater for these diverse requirements

50. System Design
 Enterprise requirements
 Technology assessment
 Business model & related info
 Examining current architecture and feasibility
 Performance analysis
 Performance analysis and monitoring
 Impact of performance issue on design

51. System Design
 Designing forperformance
 Storage management
 Access management and optimization of storage
distribution
 Maximizing network transportation
 Managing system performance
 Multimedia SystemDesign
 Systems Design Methodology
 Object Oriented Multimedia Systems

52. System Design
 System Extensibility
 Ease of upgrading / add-on / plug-in
 Reusability
 System Maintenance
 Routine jobs to upkeep the operation

53. Networked MM Systems
 Generally, networked multimedia systems
have issues to address, some of which
are:
 Traffic analysis
 Bufferdesign
 Traffic shaping
 Admission and congestion control
 Scheduling
 Standardization