Chapter 1 Introduction to Multimedia Saurabh Gupta, AP-CSE, NIEC
What is Multimedia?
• Multimedia is any combination of
– text,
– graphic art,
– sound,
– animation,
– video,
delivered by computer or electronic
means
Saurabh Gupta, AP-CSE, NIEC
Multimedia takes may forms
• Greeting Cards
• Conferencing
• Movies
• Photo albums
• Image catalogs
Saurabh Gupta, AP-CSE, NIEC
Producing a Multimedia Project
• Requires
a) creative skill
b) technology tools
c) organizational and business talent
d) knowledge of ownership and
copyright rules
Saurabh Gupta, AP-CSE, NIEC
Where Do You Begin?
• Study each element of Multimedia
• Read trade periodicals
• Visit web sites
Saurabh Gupta, AP-CSE, NIEC
Where Do You Begin?
• Learn tools to create or edit that
element
• Learn to use texts and fonts
effectively
• Learn how to make and edit colorful
images
• Learn how to animate images into
movies
• Learn how to record and edit sound
Saurabh Gupta, AP-CSE, NIEC
Types of Multimedia
• Interactive multimedia
• Hyperactive multimedia
• Linear multimedia
Saurabh Gupta, AP-CSE, NIEC
Interactive Multimedia
• Allows the user to control
– what and
– when the elements are delivered
Saurabh Gupta, AP-CSE, NIEC
Hypermedia
• Interactive Multimedia which
provides a structure of linked
elements through which the user
can navigate
Saurabh Gupta, AP-CSE, NIEC
Multimedia Project
• Software vehicle, messages and
content presented on a computer or
TV screen
– Multimedia title - if sold or shipped to
users with or without instructions
– Web page if on the www and composed
of HTML or DHTML ( Dynamic Hypertext
Markup Language)
Saurabh Gupta, AP-CSE, NIEC
Multimedia Project
• Linear - users watch from beginning
to end
• Non-linear and interactive - users are
given navigational control and can
wonder through the content
Saurabh Gupta, AP-CSE, NIEC
Authoring Tools
• Multimedia elements are “sewn”
together using tools like Authorware
– to provide facilities for creating and
editing text and images
– have extensions to drive videodisc
players and other peripherals
– playback the sound and movie elements
created with other tools
Saurabh Gupta, AP-CSE, NIEC
Requirements
• Multimedia requires:
– large amounts of digital memory and
network bandwidth;
– GUI (“gooey”) - a graphical user interface
– CD-Rom or DVD technology for storage
In the future these may be replaced by
“connected” fiber, and radio/cellular
technology
– DVD – Digital Versatile Disc
Saurabh Gupta, AP-CSE, NIEC
Delivering and Using Multimedia
• Multimedia demands bandwidth
• CD-ROMs hold 650-700 MB (80
minutes of full screen video)
• DVD-ROMs hold 4.7-18 GB
• Multimedia can be delivered on line
Saurabh Gupta, AP-CSE, NIEC
Why Multimedia?
• Multimedia enhances learning,
memory and retention
– audio stimulation - 20% retention rate
– audio/visual - up to 30% retention rate
– interactive multimedia - up to 60%
retention rate
Saurabh Gupta, AP-CSE, NIEC
Delivering and Using Multimedia
• Online uses include:
– Books and Magazines
– Movies
– News and Weather
– Education
– Maps
– Entertainment
Saurabh Gupta, AP-CSE, NIEC
Appropriate uses
• Business
• Schools
• Homes
• Public Places
– 1995 Al Gore - White House Challenge
to connect every classroom, clinic,
hospital to Information Superhighway
by 2000
Saurabh Gupta, AP-CSE, NIEC
New Technologies
• VR- Virtual Reality
– Goggles, helmets, gloves, etc. place
users “inside” a life-like experience
– View changes as user moves forward,
left/right, etc.
– Composed of thousands of geometric
to be realistic
– Will require new standards (VRML) for
transmitting virtual worlds on the web
Saurabh Gupta, AP-CSE, NIEC
Results
• Multimedia will cause radical
changes in teaching and learning
• “Teachers will become mentors and
guides along a learning path that is
student centered…” (See pp. 12-13)
• Education will shift from the
“SAGE on the STAGE to the
GUIDE at the SIDE” of each student.
Saurabh Gupta, AP-CSE, NIEC
Stages of a Project
• Planning and costing-begin with an
idea
– plan text, graphics,music, video
– develop graphic layout (“look and feel”)
– develop a structure and navigation
system
– estimate time needed to complete
– prepare budget ( if necessary)
– work up a prototype
Saurabh Gupta, AP-CSE, NIEC
Stages of a Project
• Plan Develop an idea
Identify objectives
Identify skills and resources
Develop a prototype
Estimate time and cost
Saurabh Gupta, AP-CSE, NIEC
Stages of a Project
• Designing and Producing - perform
each planned task
• Testing - test to be sure project
meets objectives and needs of client
• Delivering- package and deliver to
end user
– create CD-ROM, labels, etc.
– prepare user manual
Saurabh Gupta, AP-CSE, NIEC
Hardware
• The Macintosh as well as Windows PC
offers a combination of affordability, and
software and hardware availability.
• The Macintosh platform is better suited for
multimedia production than the Windows
platform.
• The hardware platforms provided by Apple
are better equipped to manage both,
sound and video editing.
Saurabh Gupta, AP-CSE, NIEC
Software
• Multimedia software provides
specific instructions to the hardware
for performing tasks.
• Software tools are divided into
production tools and authoring tools.
Saurabh Gupta, AP-CSE, NIEC
Creativity and
Organizational Skills
• In a multimedia project, being
creative implies knowledge of
hardware and software.
• It is essential to develop an
organized outline detailing the skills,
time, budget, tools and resources
needed for the project.
Saurabh Gupta, AP-CSE, NIEC
Developing Multimedia
• To make multimedia, you need
hardware, software, good ideas.
• To make GOOD multimedia you also
need talent and skill, organization,
time, money and the help of others.
• Teamwork is essential
Saurabh Gupta, AP-CSE, NIEC
Summary
• The basic stages of a multimedia project
are planning and costing, design and
production, testing and delivery.
• Knowledge of hardware and software, as
well as creativity and organizational skills
are essential for creating a high-quality
multimedia project.
Saurabh Gupta, AP-CSE, NIEC
Sample Project
• You will create a multimedia
demonstration of your company‟s new
product, the Staplechase 3000 (a really
nice stapler). The demonstration will
highlight three key features of the product.
End users will view the demonstration on
the company‟s Web site. On paper,
develop a basic plan for the project. The plan should include:
Saurabh Gupta, AP-CSE, NIEC
Project:
• The plan should include:
A flow chart or timeline showing the
basic flow of the project
A list of hardware and software
resources that will be required
A list of skills that will be required
A time estimate for project completion
Saurabh Gupta, AP-CSE, NIEC
Skills and Background
• 1. What are some of the skills needed
to develop good multimedia ?
• 2. What is the responsibility of each
member of the software team?
• 3. What background/training/skill is
required of each?
Saurabh Gupta, AP-CSE, NIEC
Multimedia Development Team
• Project Manager
• Multimedia Designer
• Interface Designer
• Writers
• Video Specialist
• Audio Specialist
• Multimedia Programmer
• Multimedia Producer for the Web
Saurabh Gupta, AP-CSE, NIEC
Project Manager
• Responsibilities
– Overall project
– Day to day operations and budget
– Put together good core team
– Maintain the “big picture” – the vision
• Background/skills
– Understand hardware & software
– Communication skills
– Good “people” skills- a good listener
Saurabh Gupta, AP-CSE, NIEC
Multimedia Designer
• Responsibilties:
– Overall content and structure
– Prepares blueprint for project: content, media,
interaction
– Sometime overlaps with Interface Designer
– Coordinates team
• A) Graphic Designers
• B) Instructional Designers
• C) Information Designers
Saurabh Gupta, AP-CSE, NIEC
Multimedia Designer
• Background/skills – Ability to analyze content structurally and
match it with effective presentation
– Expert with different media types
– Ability to look at information from different points of view
– Interpersonal skills
– Understand resources- both technological and human
– Solid organizational skills, attention to detail
Saurabh Gupta, AP-CSE, NIEC
Multimedia Designer
• A) Graphic designer – deals with
visuals • Illustrators ( Freehand)
• Animators ( Flash)
• Image processing specialists ( Photoshop)
Saurabh Gupta, AP-CSE, NIEC
Multimedia Designer
• Instructional Designers – deal with
subject matter
– Clear and proper presentation
– Knowledge of content
Saurabh Gupta, AP-CSE, NIEC
Multimedia Designer
• Information Designers – deal with
contents and navigation
– Structure content
– Determine user feedback and pathways
Saurabh Gupta, AP-CSE, NIEC
Interface Designer
• Responsibilities:
– Provides access to media and control to people
who use it
– Makes interface “transparent” to users (
effective use of windows, icons, backgrounds,
controls, etc.)
• Background/skills
– Familiar with different multimedia interfaces
– Knows authoring system, user testing
– Basic drawing skills
Saurabh Gupta, AP-CSE, NIEC
Writers
• Responsibilities:
– Create character, action, point of view, interactivity
– Write proposals, script actor‟s narration, write text screen( content writers)
• Background/skills:
– Background in marketing
– Ability to work within tight deadlines
Saurabh Gupta, AP-CSE, NIEC
Video Specialist
• Responsibilities:
– Coordinate videographers, sound technicians, lighting designers, set designers, script supervisors, production assistants, actors
• Background/skills:
– Skilled with QuickTime or MS Video for editing
– Macromedia Premiere for special effects
Saurabh Gupta, AP-CSE, NIEC
Audio Specialist
• Responsibilities:
– Locating and selecting suitable music and
talent
– Scheduling recording sessions
– Digitizing, editing recorded materials
• Background/skills:
– Skilled in studio recording
– Fluency in MIDI
– Experience with sequencing software
Saurabh Gupta, AP-CSE, NIEC
Multimedia Programmer • Responsibilities:
– Integrates multimedia elements into “seamless” whole using programming language or authoring system (Authorware)
– Coding displays to controlling devices
• Background/skills:
– Multimedia languages (C++, Java, Lingo)
– HTML, VRML, XML
– Ability to quickly learn new systems
Saurabh Gupta, AP-CSE, NIEC
Multimedia Producer for the Web
• Responsibilities:
– Coordinates set of pages for the web
• Background/skills:
– Knowledge of HTML, CGI scripts,
Photoshop, etc.
Saurabh Gupta, AP-CSE, NIEC
Good Multimedia
• Many multimedia systems are too passive- users click and watch
• For fully interactive systems, designers need clear picture of what happens as user interacts
• Adaptive systems modify themselves based on user input ( intelligent tutors)
Saurabh Gupta, AP-CSE, NIEC
Overview
• Importance of text in a multimedia presentation.
• Understanding fonts and typefaces.
• Using text elements in a multimedia presentation.
• Computers and text.
• Font editing and design tools.
• Multimedia and hypertext.
Saurabh Gupta, AP-CSE, NIEC
Revolution in Communication
• Using symbols for communication
relatively recent - 6,0000 years old
• 15th Century- Johann Gutenburg
printing press revolutionized
information
• Recently - another revolution - the
World Wide Web and its native
language - HTML
Saurabh Gupta, AP-CSE, NIEC
The Power of Meaning and the
Importance of Text
Titles
Menus
Navigational aids
•Words must be chosen carefully
•Words appear in:
•Test the words you plan to use
•Keep a thesaurus handy
Saurabh Gupta, AP-CSE, NIEC
Using Text in Multimedia Type terminology
•Typeface
Arial Courier
Times
•Fonts
•Points
•Styles
•Leading
•Kerning
Saurabh Gupta, AP-CSE, NIEC
Fonts and Faces
• A typeface is a family of graphic characters that includes many type sizes and styles (such as Times, Arial, Helvetica)
• A font is a collection of characters of a single size and style belonging to a typeface family (such as bold, italic)
• Font sizes are in points 1 point = 1/72 inch (measured from top to bottom of descenders in capital letter)
• X-height is the height of the lower case letter x
Saurabh Gupta, AP-CSE, NIEC
Factors affecting legibility of text
– Size.
– Background and foreground color.
– Style.
– Leading (pronounced “ledding”).
Saurabh Gupta, AP-CSE, NIEC
Styles
• Examples of styles are boldface and italic
Italic
Bold
Underlined
Saurabh Gupta, AP-CSE, NIEC
Leading and Kerning
Computers can
• adjust the line spacing (called
leading)
leading
and
• the space between pairs of letters,
called kerning
Saurabh Gupta, AP-CSE, NIEC
Fonts and Faces
• PostScript, TrueType and Master
fonts can be altered
• Bitmapped fonts cannot be altered
• The computer draws or rasterizes a
letter on the screen with pixels or
dots.
Saurabh Gupta, AP-CSE, NIEC
Cases
• When type was set by hand, the type
for a font was kept in a drawer or case,
• The upper drawer held the capital
letters, and the lower drawer held the
smaller letters
• From this we get the terms uppercase
and lowercase
Saurabh Gupta, AP-CSE, NIEC
Case Sensitive
• Password, and paths in a URL are case
sensitive ( that is “home” is different from
“HOME”)
• It is easier to read words that have a
mixture of upper and lower case letters
rather than all upper case
• Computer terms use an intercap for
readability as in PageMaker, or LastName
Saurabh Gupta, AP-CSE, NIEC
Serif and Sans Serif
• Type either has a little decoration at
the end of the letter - called a serif
• or it doesn‟t - sans serif ( “sans”
from the French meaning without)
• Examples ( Times - serif “T” )
( Arial - sans serif “T”)
• Use what is appropriate to convey
your message
Saurabh Gupta, AP-CSE, NIEC
Using Text In Multimedia
• WYSIWYG - What you see is what you get!
• Aim for a balance between too much text and too little
• Make web pages no more than
1 to 2 screenfuls of text
• Bring the user to the destination with as few actions as possible
Saurabh Gupta, AP-CSE, NIEC
Text Font Design Tips • Use the most legible font available
• Use as few different faces as possible ( too
many called “ransom-note” typography
• Use bold and italics to convey meaning
• Adjust line spacing ( leading)
• Adjust the spacing between letters in
headings to remove gaps
• Use colors and background to make type
stand out
• Use meaningful word for links and menus
Saurabh Gupta, AP-CSE, NIEC
More Text Font Design Tips
• Anti-aliasing or dithering blends colors
along the edges of letters to create gentle
effect.
• Experiment with shadows
• Surround headlines with white space
• Try attention grabbing effect with color,
word art or large drop letters at the
beginning of text
Saurabh Gupta, AP-CSE, NIEC
Menus For Navigation
• A Multimedia project or web site
should include:
– content or information
– navigation tools such as menus, mouse
clicks, key presses or touch screen
– some indication or map of where the
user is in the presentation
Saurabh Gupta, AP-CSE, NIEC
Buttons for Interaction
• Buttons are objects that make things
happen when they are clicked
• Use common button shapes and
sizes
• Label them clearly
• BE SURE THEY WORK!
Saurabh Gupta, AP-CSE, NIEC
Fields for Reading
• Reading from a computer screen is
slower than from a book
• People blink 3-5 times/minute, using
a computer and 20-25 times/minute
reading a book
• This reduced eye movement causes
fatigue, dryness
• Try to present only a few paragraphs
per page
Saurabh Gupta, AP-CSE, NIEC
Portrait vs. Landscape
• Monitor use wider-than-tall aspect
ratios called landscape
• Most books use taller-than- wide
orientation, called portrait
• Don‟t try to shrink a full page onto a
monitor
portrait
landscape
Saurabh Gupta, AP-CSE, NIEC
HTML Documents • Standard document format on the web is
called Hypertext Markup Language ( HTML)
• Originally designed for text not multimedia - now being redesigned as Dynamic HTML ( DHTML), which uses CSS (Cascading Style sheets) and permits defining text choices.
• Specify typefaces, sizes colors and properties by “marking up” the text with tags (such as <B>, </B>)
Saurabh Gupta, AP-CSE, NIEC
HTML Documents
• The Font tag is used to specify the font to be displayed (if present)
• <font face = “Verdana, Arial, Times”>
• If those fonts are not on the system, the default is used ( see p. 55-57 for common fonts)
Saurabh Gupta, AP-CSE, NIEC
Symbols and Icons
• Symbols act like “visual words” to convey meaning, (called icons)
– MAC - trash can
– Windows - hourglass
• Icons and sound are more easily remembered than words
• It is useful to label icons for clarity
• See “smileys” in textbook (p. 61)
Saurabh Gupta, AP-CSE, NIEC
Animating Text
• To grab a viewer‟s attention:
– let text “fly” onto screen
– rotate or spin text, etc.
• Use special effects sparingly or they
become boring
Saurabh Gupta, AP-CSE, NIEC
Computers and Text
• Mac standard - 72 pixels/ inch
• PC - VGA - 96 pixels/inch
• Screen ( 640 pixels across x 480
down, called 640 x480 resolution)
• Today much higher resolution
possible
Saurabh Gupta, AP-CSE, NIEC
Fonts “Wars”
• Apple - Adobe PostScript page description
font language
– describes an image in terms of
mathematical constructs (Bezier curves)
– Can be scaled larger or smaller
– Currently > 6,000 typefaces available
• Apple & Microsoft created TrueType
Saurabh Gupta, AP-CSE, NIEC
Computers and Text
Allow text to be drawn at any size without
“jaggies”, by anti-aliasing the edges of the
characters
Saurabh Gupta, AP-CSE, NIEC
Fonts and Characters
• Fonts smaller than 12 point are not
very legible on a monitor
• Never assume the fonts installed on your
computer are on all computers
• Stay with TrueType fonts ordinarily
• ASCII character set - most common
• Extended Character set - used for HTML
• UNICODE –supports characters for all
known languages
Saurabh Gupta, AP-CSE, NIEC
Unicode
• Developed in 1989 for multilingual text
• Contains 65,000 characters form all known
languages and alphabets
• Where several languages share a set of
symbols, they are grouped into a
collection called scripts ( eg. Latin,
Arabic, Cyrillic, Greek, Tibetan, etc.)
• Shared symbols are unified into
collections called scripts
Saurabh Gupta, AP-CSE, NIEC
Unicode
• Numbers
• Mathematical symbols
• Punctuation
• Arrows, blocks and drawing shapes
• Technical symbols
Saurabh Gupta, AP-CSE, NIEC
Mapping Text Across Platforms
• Viewing a presentation on either
MAC and PC reveals differences
• Fonts must be mapped from one
machine to another
• If same font doesn‟t exist on the
other machine, one is substituted
( called font substitution)
• To avoid this, convert to bitmaps
Saurabh Gupta, AP-CSE, NIEC
Representing Languages
• Some contain different symbols
• Others represent an entire concept
with a single symbol (as in some
Asian languages)
• Translating into another language is
called localization
Saurabh Gupta, AP-CSE, NIEC
Font Editing and Design Tools
• Allow you to create your own fonts
– ResEdit for MAC
– Fontographer (from Macromedia) caan
be used to create Postscript, TrueType
and bitmapped fonts for MAC, PB, SUN
includes a freehand drawing tool
– 3D programs, such as COOL 3D and
HotTEXT, create special effects
– See text for descriptions
Saurabh Gupta, AP-CSE, NIEC
Hypermedia and Hypertext
• Hyper media provides a structure of links
• Hypertext words are linked to other
elements
• Hypertext is usually searchable by
software robots
Saurabh Gupta, AP-CSE, NIEC
Hypermedia and Hypertext
• Multimedia - combines text, graphics
and audio
• Interactive multimedia - gives user
control over what and when content
is viewed (non-linear)
• Hypermedia -provides a structure of
linked elements through which user
navigates and interacts
Saurabh Gupta, AP-CSE, NIEC
Hypermedia Structures
Hypermedia elements are called
nodes
Nodes are connected using links
A linked point is called an anchor
Saurabh Gupta, AP-CSE, NIEC
Hypermedia Structures
• Link - connections between
conceptual elements (navigation
pathways and menus)
• Node - contains text, graphics sounds
• Anchor - the reference from one
document to another document,
image, sound or file on the web
• Link anchor - where you came from
Saurabh Gupta, AP-CSE, NIEC
Hypermedia and Hypertext • Doug Englebart - inventor of mouse
• 1965 Ted Nelson coined the word
“hypertext”
• Computer-based hypertext systems
will fundamentally alter the way
humans think, approach literature
and the expression of ideas
• Hotlinks - lead user from one
reference to another
Saurabh Gupta, AP-CSE, NIEC
Using Hypertext
• Searching for words
– boolean search using AND, OR, NOT
– truncation - using only part of word,
such as geo might yield result with
geology, geography, George, etc.
• Search engines employ “robots” to
visit web pages and create indexes.
Saurabh Gupta, AP-CSE, NIEC
Hypertext Tools
• Building or authoring
– builder creates links, identifies nodes,
generates an index of words
• Reading
– both linear and increasingly non-linear
• Becoming more comfortable with
non-linear hypertext systems will
change the way we think….
Saurabh Gupta, AP-CSE, NIEC
Overview
• Introduction to sound.
• Multimedia system sound.
• Digital audio.
• MIDI audio.
• Audio file formats.
Saurabh Gupta, AP-CSE, NIEC
Overview
• MIDI versus digital audio.
• Adding sound to multimedia project.
• Professional sound.
• Production tips.
Saurabh Gupta, AP-CSE, NIEC
Power of Sound
• Vibrations in the air create waves of pressure that are perceived as sound.
• Sound waves vary in sound pressure level (amplitude) and in frequency or pitch.
• „Acoustics‟ is the branch of physics that studies sound.
• Sound pressure levels (loudness or volume) are measured in decibels (dB).
• Humans hear sound over a very broad range (see p. 91)
Saurabh Gupta, AP-CSE, NIEC
Sound
• Sound is energy, caused by molecules vibrating
• Too much volume can permanently damage your ears and hearing
• The perception of loudness depend on the frequency or pitch
• Harmonics cause the same note played on a cello to sound different from one played on a piano.
Saurabh Gupta, AP-CSE, NIEC
Using Sound in Multimedia
• You need to know
– How to make sounds
– How to record and edit sounds on the
computer
– How to incorporate sounds into your
multimedia project
Saurabh Gupta, AP-CSE, NIEC
Multimedia System Sounds
• System sounds are assigned to various system events such as startup and warnings, among others.
• Macintosh provides several system sound options such as glass, indigo, laugh.
• In Windows, available system sounds include start.wav, chimes.wav, and chord.wav.
• Multimedia sound is either digitally recorded audio or MIDI (Musical Instrumental Digital Interface) music.
Saurabh Gupta, AP-CSE, NIEC
Multimedia System Sounds
• Mac and Windows have built in
sound recorders
Saurabh Gupta, AP-CSE, NIEC
Multimedia System Sounds
• Windows system sounds are .WAV
files in the Windows\Media directory
• MS Office includes additional sounds
• You can add your own sounds by
including them in the Windows\Media
directory and selecting them from
the Sound Control Panel
Saurabh Gupta, AP-CSE, NIEC
MIDI vs. Digital Audio
• MIDI ( Musical Instrument Digital
Interface) is a communications
standard developed in the 1980‟s for
electronic instruments and
computers.
• It allows instruments from different
manufacturers to communicate.
Saurabh Gupta, AP-CSE, NIEC
MIDI vs. Digital Audio
• MIDI data is NOT digitized sound- it is music stored in numeric format
• Digital audio is a recording, which depend on your sound system
• MIDI is a score and depends on both the quality of the instruments and the sound system
• Quality depends on end user‟s device rather than on the MIDI device and is device dependent.
Saurabh Gupta, AP-CSE, NIEC
Making MIDI Audio
• Creating a MIDI score requires:
– Knowledge of music and some talent
– Ability to play a musical instrument
– Sequencer software
– Sound synthesizer • Built into PC board
• Add-on for MAC
• MIDI can synthesize over 100 instruments
Saurabh Gupta, AP-CSE, NIEC
Making MIDI Audio
You will need:
• Sequencer Software (Smart Score)
• A Sound synthesizer ( built into PC
sound board, an add on for MAC)
• MIDI keyboard or device
• Ability to play the piano and music
theory background
• or a hired “expert”
Saurabh Gupta, AP-CSE, NIEC
MIDI
• A MIDI file is a list of commands that
are recordings of musical actions,
that when sent to a MIDI player
results in sound
• MIDI data is device dependent
• MIDI represents musical instruments
and is not easily used to playback
spoken dialog
Saurabh Gupta, AP-CSE, NIEC
MIDI Audio
• MIDI is a shorthand representation of music stored in numeric form.
• Since they are small, MIDI files embedded in web pages load and play promptly.
• Length of a MIDI file can be changed without affecting the pitch of the music or degrading audio quality.
• Working with MIDI requires knowledge of music theory.
Saurabh Gupta, AP-CSE, NIEC
Digital Audio
• Digital audio is a representation
of the original sound
• Sampling rate is measured in
kilohertz (kHz)
Click to play
Saurabh Gupta, AP-CSE, NIEC
Digital Audio
• Digital audio represents a sound
stored in thousands of numbers or
samples.
• Digital data represents the loudness
at discrete slices of time.
• It is NOT device dependent and
should sound the same each time it
is played
• It is used for music CD‟s
Saurabh Gupta, AP-CSE, NIEC
Digital Audio
• The three sampling frequencies most often used in multimedia are CD-quality 44.1 kHz, 22.05 kHz and 11.025 kHz.
• The number of bits used to describe the amplitude of sound wave when sampled, determines the sample size.
• Digital audio is device independent.
• The value of each sample is rounded off to the nearest integer (quantization).
Saurabh Gupta, AP-CSE, NIEC
Preparing Digital Audio
• Balance file size versus
quality
• Set recording levels
• Edit the recording
Saurabh Gupta, AP-CSE, NIEC
Preparing Digital Audio
• Balance file size versus quality
To calculate file size in bytes:
Mono: sampling rate duration of recording
in seconds (bit resolution 8) 1
Stereo: sampling rate duration of recording
in seconds (bit resolution 8) 2
Saurabh Gupta, AP-CSE, NIEC
Digital Audio Editing
• Once a recording had been completed, it
almost always needs to be edited.
• Basic sound editing operations include:
trimming, splicing and assembly, volume
adjustments and working on multiple
tracks.
Saurabh Gupta, AP-CSE, NIEC
Digital Audio Editing
Additional available sound editing
operations include format conversion,
resampling or downsampling, fade-ins and
fade-outs, equalization, time stretching,
digital signal processing, and reversing
sounds.
Saurabh Gupta, AP-CSE, NIEC
MIDI vs. Digital Audio
• MIDI data and digital audio are like
vector and bitmapped graphics:
• Digital audio like bitmapped image –
samples original to create a copy
• MIDI – like vector graphic- stores
numeric data to recreate sound
Saurabh Gupta, AP-CSE, NIEC
MIDI vs. Digital Audio
• MIDI data is device dependent; digital
audio is not
• MIDI sounds (like vector graphics)
are different on different devices;
• Digital sounds are identical even on
different computers or devices.
Saurabh Gupta, AP-CSE, NIEC
MIDI Advantages
• MIDI file are much more compact and take up less memory and system resources
• MIDI files embedded in web pages load and play much faster than digital
• You can change the length of a MIDI file by varying its tempo
• With high quality MIDI devices, MIDI files may actually sound better than digital
Saurabh Gupta, AP-CSE, NIEC
MIDI Disadvantages
• MIDI represents musical instruments
not sounds and will be accurate only
if your playback device is identical
to the production device
• MIDI sound is inconsistent
• MIDI cannot be easily used to
reproduce speech
Saurabh Gupta, AP-CSE, NIEC
Digital Audio Advantages
• Digital audio sound is consistent and
device independent
• A wide selection of software support
is available for both MAC and PC
• A knowledge of music theory is not
required for creating digital audio,
but usually is needed for MIDI
production
Saurabh Gupta, AP-CSE, NIEC
Choose MIDI data
• If you don‟t have enough RAM
memory, or bandwidth for digital
audio
• If you have a high quality sound
source
• If you have complete control over the
playback hardware
• If you don‟t need spoken dialog
Saurabh Gupta, AP-CSE, NIEC
Choose Digital Audio
• If you don‟t have control over the
playback hardware
• If you have the computing resources
and bandwidth to handle the larger
digital files
• If you need spoken dialog
Saurabh Gupta, AP-CSE, NIEC
Digital Audio
• You can digitize sound from a
microphone, synthesizer, tape
recording TV broadcast, or CD‟s.
• Digitized sound is sampled every nth
of a second. The more often you take
the sample, the better the sound.
• Sample sizes are either 8 or 16 bits
and common frequencies are11.025,
22.05, and 44.1 kHz (See pp. 209- 211)
Saurabh Gupta, AP-CSE, NIEC
Digital Audio
• To prepare digital audio from analog
media, record it from a device, like a
tape recorder, into your computer
using digitizing software.
• Balance the sound quality with your
available RAM
• Set proper recording levels for a
good clear recording
Saurabh Gupta, AP-CSE, NIEC
File Size vs. Quality
• Audio resolution determines the
accuracy with which a sound is
digitized. (More bits in the sample
size produces better quality and
larger files)
• Stereo recordings are more realistic
and require twice as much storage
space and playback time.
• Mono files tend to sound “flat”
Saurabh Gupta, AP-CSE, NIEC
Editing Digital Recordings
• Apple‟s QuickTime Player Pro provides for primitive playback and editing
• Sonic Foundry‟s Sound Forge is a more serious sound editor
• These can be used to trim, splice, volume adjustment and format conversion as well as special effects
Saurabh Gupta, AP-CSE, NIEC
Audio File Formats
• A sound file‟s format is a recognized methodology for organizing data bits of digitized sound into a data file.
• On the Macintosh, digitized sounds may be stored as data files, resources, or applications such as AIFF or AIFC.
• In Windows, digitized sounds are usually stored as WAV files.
• Both can use MIDI files (.mid)
Saurabh Gupta, AP-CSE, NIEC
Audio File Formats
• CD-ROM/XA (Extended Architecture)
format enabled several recording
sessions to be placed on a single
CD-R (recordable) disc.
• Linear Pulse Code Modulation is
used for Red Book Audio data files
on consumer-grade music CDs.
Saurabh Gupta, AP-CSE, NIEC
Sound for the World Wide Web
• To play MIDI sound on the web
– wait for the entire file to download and
play it with a helper application
– stream the file, storing it in the buffer and
playing it while it downloads
• Streaming is dependent on the
connection speed
• FLASH allows sound to be integrated
in a multimedia presentation,
controlled by buttons and saved as
.mp3 Saurabh Gupta, AP-CSE, NIEC
Adding Sound to a
Multimedia Project
• Decide what sounds you will need and
include them in the story board or cue
sheet.
• Decide whether to use MIDI or digital
audio
• Acquire source material (record/buy)
• Edit the sounds
• Test the sounds to be sure they are
timed properly
Saurabh Gupta, AP-CSE, NIEC
Adding sound to Multimedia
• CD- quality audio
Standard is ISO 10149, a.k.a. the “Red Book Standard”
Sample size is 16-bit
Sample rate is 44.1 kHz
11 seconds of audio uses 1.94 MB of space
Saurabh Gupta, AP-CSE, NIEC
Professional Sound
• The Red Book Standard- ISO 10149
– ( 16 bits at 44.1 kHz) allows accurate
reproduction of all sounds humans can
hear
– Software such as Toast and CD-Creator
can translate digital files from CD‟s
directly into a digital sound editing file
or decompress.mp3 files into CD-Audio
Saurabh Gupta, AP-CSE, NIEC
Professional Sound
• Compression techniques reduce space but
reliability suffers.
• Space can be conserved by downsampling
or reducing the number of sample slices
taken per second.
• File size of digital recording (in bytes) =
sampling rate X duration of recording (in
secs) X (bit resolution/8) X number of
tracks.
Saurabh Gupta, AP-CSE, NIEC
Advanced Sound Management
• Scripting Languages such as Open
Script (Toolbook), LINGO(Director),
or Action Script ( FLASH) provide
better control over audio playback
• Requires some programming
knowledge
Saurabh Gupta, AP-CSE, NIEC
Production Tips
• Vaughn‟s Law of Minimums - there is
an acceptable level of adequacy that
will satisfy the audience;
• If your handheld microphone is good
enough to satisfy you and your
audience, conserve your money and
energy.
Saurabh Gupta, AP-CSE, NIEC
Production Tips
• Recording on inexpensive media
rather than directly to disk
prevents the hard disk from being
overloaded with unnecessary data.
• The equipment and standards
used for the project must be in
accordance with the requirements.
• Sound and image synchronization
must be tested at regular intervals
Saurabh Gupta, AP-CSE, NIEC
Production Tips
• Audio recording - use CD‟s, or VCR
tapes, or DAT ( digital audio tape)
tapes
• Create a good database to organize
your sounds, noting the counter and
content
• Testing and Evaluating- (delaying a
fast machine if needed to sync with
animation)
Saurabh Gupta, AP-CSE, NIEC
Production Tips
• Copyright Issues
• Securing permission for the use of
sounds and music is the same as for
images
• Can buy royalty-free digitized sound
clips
• DO NOT use someone‟s original
work without permission!
Saurabh Gupta, AP-CSE, NIEC
Summary
• Vibrations in air create waves of pressure
that are perceived as sound.
• Multimedia system sound is digitally
recorded audio or MIDI (Musical
Instrumental Digital Interface) music.
• Digital audio data is the actual
representation of a sound, stored in the
form of samples.
Saurabh Gupta, AP-CSE, NIEC
Summary
• MIDI is a shorthand representation of music stored in numeric form.
• Digital audio provides consistent playback quality.
• MIDI files are much smaller than digitized audio.
• MIDI is device dependent digital audio is not
• MIDI files sound better than digital audio files when played on high-quality MIDI device.
Saurabh Gupta, AP-CSE, NIEC
Overview
• Creation of multimedia images.
• Creation of still images.
• Colors and palettes in multimedia.
• Image file types used in multimedia.
Saurabh Gupta, AP-CSE, NIEC
Before You Start to Create:
• Plan your approach using flowcharts and storyboards
• Organize your tools ( text, buttons, sounds, etc.)
• Use multiple monitors (especially for a program like Director where changes in one window are visible in the presentation window)
Saurabh Gupta, AP-CSE, NIEC
Making Still Images
• Bitmaps ( or paint graphics) – used for
photo-realistic images and detailed
drawings
• Vector graphics – used for lines, polygons
and other mathematical objects
• Saved as GIF,JPEG,PNG files with
compression
Saurabh Gupta, AP-CSE, NIEC
Making Still Images
• Stills are drawn in one of two
ways and are usually compressed
Bitmaps
Vector-drawn graphics
Saurabh Gupta, AP-CSE, NIEC
Bitmaps
• Bitmap is derived from the words
„bit‟, which means the simplest
element in which only two digits are
used, and „map‟, which is a two-
dimensional matrix of these bits.
• A bitmap is a data matrix describing
the individual dots of an image.
Saurabh Gupta, AP-CSE, NIEC
BITMAPS
• A simple information matrix describing the dots or pixels which make up the image
• Make it with paint or drawing program
• Grab it and (save it) then paste it into you application
• Scan or digitize an image
Saurabh Gupta, AP-CSE, NIEC
Bitmaps
Bitmaps are an image format suited for
creation of:
– Photo-realistic images.
– Complex drawings.
– Images that require fine detail.
Saurabh Gupta, AP-CSE, NIEC
Bitmaps
• Bitmapped images are known as
paint graphics.
• A bitmap is made up of individual
dots or picture elements known as
pixels or pels.
• Bitmapped images can have varying
bit and color depths.
Saurabh Gupta, AP-CSE, NIEC
Bitmaps
Bitmaps can be inserted by:
– Using clip art galleries.
– Using bitmap software.
– Capturing and editing images.
– Scanning images.
Saurabh Gupta, AP-CSE, NIEC
Clip Art
• Available from many sources on the
web or on CD ( such as PHOTODISC)
• Often included with packages such
as Corel Draw, Office, etc.
• Can manipulate some properties
such as brightness, color, size
• Can paste it into an application
Saurabh Gupta, AP-CSE, NIEC
Clip Art Galleries
• A clip art gallery is an assortment of graphics, photographs, sound, and video.
• Clip arts are a popular alternative for users who do not want to create their own images.
• Clip arts are available on CD-ROMs and on the Internet.
Saurabh Gupta, AP-CSE, NIEC
Using Bitmap Software
The industry standard for bitmap
painting and editing programs are:
• Adobe's Photoshop and Illustrator.
• Macromedia's Fireworks.
• Corel's Painter.
• CorelDraw.
• Quark Express.
Saurabh Gupta, AP-CSE, NIEC
Bitmap Software
• Primitive Paint programs included with
windows and MAC
• Director included a powerful image editor
with advanced tools such as onion-skin
and image filtering
• Adobe Photoshop and Fractal Design‟s
Painter are more sophisticated painting
and editing tools
Saurabh Gupta, AP-CSE, NIEC
Tip
• Use paint program for cartoon, text,
icons, symbols, buttons, or graphics.
• For photo-realistic images first scan
a picture, then use a paint or image
editing program to refine or modify
them
Saurabh Gupta, AP-CSE, NIEC
Capturing and Editing Images
• Capturing and storing images directly
from the screen is another way to
assemble images for multimedia.
• The PRINT SCREEN button in Windows
and COMMAND-CONTROL-SHIFT-4
keystroke on the Macintosh copies the
screen image to the clipboard.
• From there you can insert it into a paint
program or other application.
Saurabh Gupta, AP-CSE, NIEC
Advanced Image Editing
• Image editing programs allow you to
insert and remove images from
photos
• Enable you to alter and distort
images, add and delete elements
• Morphing blends two images so that
one seems to “melt” into the other
Saurabh Gupta, AP-CSE, NIEC
Scanning Images
• Everyday objects can be scanned
and manipulated using tools such as
Photoshop
• Traditional artwork created with pen
and ink or watercolors can be
created and scanned
Saurabh Gupta, AP-CSE, NIEC
Vector Drawings
• Vector graphics are defined using
formulas
– RECT 0,0,200,200,RED,BLUE
Saurabh Gupta, AP-CSE, NIEC
Vector Drawing
• Used for lines, rectangles, geometric objects- stored mathematically
• CAD ( computed aided design) programs created complex and geometric renderings needed by architects and engineers
• Graphic artists use vector graphics to eliminate the “jaggies”
• Programs for 3-D animation use vector graphics for rotation,spinning and shading
Saurabh Gupta, AP-CSE, NIEC
How Vector Drawing Works
• Vector drawn object are drawn to the computer screen using a fraction of the memory space required by a bitmap.
• A vector is a line described by its endpoints, and sometimes direction
• A rectangle might be described as: – RECT, 0, 0,200, 200
– Starts at 0,0 and extends 200 pixels horizontally and 200 pixels downward from the corner ( a square)
– RECT, 0, 0,200, 200, red, blue
– This is the same square with a red border filled with blue
Saurabh Gupta, AP-CSE, NIEC
Vector- Drawn vs. Bitmaps
• Colored square as a vector contains < 30 bytes of data
• The same square as a bitmapped image would take 5,000 bytes to describe ( 200x200)/8) and using 256 colors would require 40K as a bitmap
((200x 200) / 8 X 8)
• Vector objects are easily scalable
• Sometimes a single bitmap gives better performance than many vector images required to make the same image
Saurabh Gupta, AP-CSE, NIEC
Converting Between
Bitmaps and Vectors
• Most drawing programs offer several file formats for saving and converting images.
• Converting bitmaps to drawn object is more difficult and is called autotracing
• It computes the bounds of an object and its colors and derives the polygon that most nearly describes it
• It is available in some programs such as Adobe Streamline
Saurabh Gupta, AP-CSE, NIEC
Vectors vs. Bitmaps
–Vector drawings are easily
scaled
–Vector files are usually smaller
–Calculation time can draw
resources
–Bitmaps cannot easily be
converted to vector
–Vector drawings require plug-ins
Saurabh Gupta, AP-CSE, NIEC
3-D Drawing and Rendering
• Drawing in 3-D on 2 2-D surface or screen
takes practice and skill
• Software helps to render ( or represent)
the image in visual form- but these
programs have a steep learning curve.
• Object in 3-D space carry many properties,
shape color, texture, location… and a
scene often contains many objects
Saurabh Gupta, AP-CSE, NIEC
3-D Drawing
• 3-D software usually offers:
Directional lighting
Motion
Different perspectives
Saurabh Gupta, AP-CSE, NIEC
3-D Drawing
• 3-D creation tools include:
Ray Dream Designer
Caligari True Space 2
Specular Infini-D
form*Z
Saurabh Gupta, AP-CSE, NIEC
Modeling 3-D objects
• Start with a shape ( block, cylinder,
sphere, …)
• You can draw a 2-D object and extrude or
lathe it into the third dimension
• Extrude – extends the shape
perpendicular to the shapes outline
• A lathed shape is rotated around a defined
axis to create the 3-D object.
Saurabh Gupta, AP-CSE, NIEC
Modeling 3-D objects
• Once a 3-D object has been created, you can apply color and texture to make it look realistic
• To model a scene, place all the objects into 3-D space and set up lighting effects and shadows.
• Objects will reflect or flare where light is most intense.
Saurabh Gupta, AP-CSE, NIEC
Modeling 3-D objects
• Add a background or set a camera view from which you will view the scene
• Shading can be applied in many ways ( See p. 304)
• Finally, the scene must be rendered- using the algorithms to apply the effects you have specified on the objects
• Rendering requires great computer power and can often take hours for a single image
Saurabh Gupta, AP-CSE, NIEC
Modeling 3-D objects
A scene can use different types of shading
Ray
tracing
Phong
shading
Gourand
shading Flat
shading
Saurabh Gupta, AP-CSE, NIEC
Color
• Natural Light and Color
– Quantum Theory of Light (Max Planck 19th Century and 20th Century Niels Bohr – photons)
Atoms produce unique colors as light passes
through
Light travels in the form of photons, or quanta
Saurabh Gupta, AP-CSE, NIEC
Color
• Natural Light and Color
– Quantum Theory of Light
– Color is the frequency of visible light
– ROY G. BIV ( increasing frequencies)
– Infrared | Visible Light | Ultraviolet
– White light is a mixture of all the frequencies
Saurabh Gupta, AP-CSE, NIEC
Color • Computerized color
Computers combine red, green, and blue (RGB) light
Bit depth determines the number of possible colors
1-bit
2 colors 4-bit
16 colors
8-bit
256 colors
24-bit
16,777,216 colors
Saurabh Gupta, AP-CSE, NIEC
Color
• Cornea of your eye focuses light rays onto
the retina to stimulate rods and cones
which transmit the patterns of color
information to the brain.
• ( Cones are sensitive to red, green and
blue light.)
• Green, blue, yellow.orange,purple, pink,
brown black, gray and white are most
common colors in all cultures.
Saurabh Gupta, AP-CSE, NIEC
Color
• Color and Culture
– Western culture: Red = anger, danger
Black = death, funerals
– Eastern culture Red = happiness
White = death, funerals
( Eastern Weddings and restaurants most often
use RED )
Internet study (p.142) world‟s favorite color is
blue
Saurabh Gupta, AP-CSE, NIEC
Color • Psychology of Color – how you perceive it
• Computer monitors produce color with red,
green and blue light – the ADDITIVE primary
colors. Tiny red, blue and green dots on the
screen, light up when bombarded by
electrons.
• The reflected light from a printed page is
SUBTRACTIVE primary colors ( cyan,
magenta, yellow and a little black)
Saurabh Gupta, AP-CSE, NIEC
Color
• Computerized Color
• Monitors and Color – most monitors today
are set to display 640 X 480 pixels and 256
colors, can be adjusted for more
• Called VGA ( Video Graphics Array)
• Minimum configuration for Windows and
MAC
• More colors requires more memory
Saurabh Gupta, AP-CSE, NIEC
Color Models • Additive Color: RGB
– Describes colors that emanate from glowing bodies such as lights, TV, and computer monitors
• In additive color models, mixing two colors results in a brighter color
• Overlapping colors from 3 projectors produces new colors: – red+ green -> yellow
– green+ blue -> cyan
– red + blue -> magenta
Saurabh Gupta, AP-CSE, NIEC
Color Models
• Subtractive Color : CMYK
– Most object reflect light
– Mixing two colors creates a darker one
– Similar to pain and printer‟s ink
– Primary colors are cyan, magenta, yellow, which are complements of red, green and blue, respectively
– Where 3 inks overlap, there is black ( gray)
Saurabh Gupta, AP-CSE, NIEC
Color
• Computer Color Models
• Color of a pixel is expressed as the amount of red, green and blue ( RGB)
• HSB ( hue, saturation, brightness) and HSL
( hue, saturation, lightness) models specify color as an angle from 0 –360 degrees on a color wheel and saturation, brightness, and lightness as percentages.
• 100% Lightness = white
• Saturation is the intensity of the color Other color models are used for TV, photos and other media
Saurabh Gupta, AP-CSE, NIEC
Color Palettes • Palettes or color look up tables (CLUT)
are mathematical tables that define the color of a pixel displayed on the screen
• Paint programs provide a palette tools for displaying available colors – not uniform across programs or platforms
• Color graphics adaptors work with 256 shades of each color producing over 16 million colors (256 x 256x 256)
Saurabh Gupta, AP-CSE, NIEC
Color Harmony
• Certain combinations of colors tend
to be pleasing. They arise from the
color harmony schemes:
– Monochromatic
– Complementary
– Analogous
– Triadic
Saurabh Gupta, AP-CSE, NIEC
Color Harmony Schemes
• Primary colors: red, yellow and blue
• Secondary colors: obtained by mixing two primary colors - orange violet, green
• Tertiary colors: obtained by mixing equal amounts of a primary and secondary color - red-violet, blue-violet, blue-green, yellow-green, yellow-orange, red-orange
• Warm (yellow, orange, red) or cool ( blue, green) colors
Saurabh Gupta, AP-CSE, NIEC
Color Harmony Schemes
• Monochromatic
– all colors have hues that are the same
or within a few degrees of one another
– colors vary in saturation or brightness,
but hue is consistent
– enhances cohesiveness to overall
layout of web page
Saurabh Gupta, AP-CSE, NIEC
Color Harmony Schemes
• Complementary
– uses a pair of complementary hues,
which appear opposite one another on a
color wheel
– one color is dominant, the other is an
accent
– use the dominant hue to fill the large
areas
Saurabh Gupta, AP-CSE, NIEC
Color Schemes
• Analogous
– two colors which lie close together on a color wheel
– often echo the colors found in nature
– pleasing combinations ( such as orange, yellow, green)
– more interesting if the colors do not have the same brightness and saturation
Saurabh Gupta, AP-CSE, NIEC
Color Schemes
• Triadic
– Any 3 colors, spaced equally around a color
wheel
– Color hues form a triad
– Offers wide variety of choice and can create
excitement
– Can be overpowering unless colors chosen
vary in brightness and saturation, or the
number of text and background are limited
Saurabh Gupta, AP-CSE, NIEC
Color in Text and Background
• Text should be legible
• Contrast between text and background is important
• Dark text on light background is best or one with high brightness and low saturation
• Avoid combinations that differ only in their blue component ( yellow on white)
• Avoid red-green, red-blue, magenta-green combinations which cause vibration and eye fatigue.
Saurabh Gupta, AP-CSE, NIEC
Palette Flashing Problem
• Palette Flashing occurs when you use a
series of images each with its own color
palette. When the new image replaces the
older one a flash occurs on the screen - a
serious problem in multimedia
• Solution
– use a single palette for all project images or
– fade each image to white or black before
showing the next image since white and black
are present in most palettes
Saurabh Gupta, AP-CSE, NIEC
Dithering
• Dithering is a process where the color
value of each pixel is changes to the
closest matching color value in the target
palette, using a mathematical algorithm
• It “averages” the color over an area and is
usually close to the original color
• Dithering software is usually built into
image editing and multimedia programs
Saurabh Gupta, AP-CSE, NIEC
Image File Formats
• MAC has a single standard format PICT
• Windows uses device independent bitmaps DIBs written as .bmp files, which is a windows bitmap file
• TIFF ( tagged interchange file formats) are universal bitmap files – used in desktop publishing
• Adobe creates .psd files for photoshop
• See pp. 150-151 for other formats
Saurabh Gupta, AP-CSE, NIEC
Image File Formats
• Be sure that your program can
import the files that you create or
save.
• Most common bitmap formats for the
web are GIF and JPEG, since all
browsers can display them
Saurabh Gupta, AP-CSE, NIEC
The Power of Animation
• Animation grabs attention
• Transitions are simple forms
of animation
Wipe
Zoom
Dissolve
Saurabh Gupta, AP-CSE, NIEC
Principles of animation
• How Animation Works
Persistence of vision
Still images are flashed in sequence
Frame rate measures the speed of
change
Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
• Persistence of Vision -biological
phenomenon - an object seen by the
human eye remains mapped on the
retina for a brief time after viewing.
• Causes the visual illusion of
movement, when images change
slightly and rapidly
Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
• Television video creates 30 frames per
second
• Movies are shot at a rate of 24 frames
per second and replayed at 48 frames
per second
• Both are used to create motion and
animation
Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
• Cel Animation
Keyframes identify the start and end of
action
The process of filling in the action is
called tweening
Saurabh Gupta, AP-CSE, NIEC
Animation Techniques
• Cel Animation
– The technique made famous by Disney
– Progressively different graphics on each frame of movie film
– Clear celluloid sheets were used to draw each frame
– ( 24 frames/sec. * 60 sec/min) = 1440 separate frames needed to produce one minute of a movie
Saurabh Gupta, AP-CSE, NIEC
Animation Techniques
• Cel Animation
– Begins with keyframes (first and last frames of an action)
– Tweening – the series of frames drawn in between the first and last
– Originally hand drawn and “flipped” through to check the “motion”
– Now replaced by computer generated graphics
Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
• Computer Animation
Kinematics is the study of motion of
jointed structures
Saurabh Gupta, AP-CSE, NIEC
Computer Animation
• Based on the same model as cel
animation
– Uses layers, keyframes, and tweening
techniques
– Inks special methods for computing RGB pixel
values, providing edge detection and layering
so that images can blend or produce
transparencies, inversions and effects
– Speed of the animation depends on computer;
– If it is display is greater than 1/15 sec,
animation may seem slow and jerky
Saurabh Gupta, AP-CSE, NIEC
Kinematics • Study of movement and motion of
structures that have joints, (such as a person or a walking dog)
• Complex- need to calculate position, velocity, rotation and acceleration of all joint and body parts involved
• Inverse kinematics – process of linking objects together and define their relationships and limits and then drag the parts and let the computer calculate the result ( for example, connect hands and arms and bent the elbow in various directions)
• Fractal Design‟s Poser – a 3-D modeling program Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
Morphing is the process of
transitioning from one image to
another
Saurabh Gupta, AP-CSE, NIEC
Morphing
• A special effect in which one image
transforms into another
• Process involves connecting a series
of key points, which are mapped
from the start image to the end image
to make a smooth transition
• ( See p.328)
Saurabh Gupta, AP-CSE, NIEC
Principles of Animation
• Animation file formats
Windows Media – .AVI, .ASF, or .WMV
Apple QuickTime – .QT or .MOV
Motion Video – .MPG or .MPEG
Flash – .SWF
Shockwave – .DCR
Animated GIF – .GIF
Saurabh Gupta, AP-CSE, NIEC
Animation File Formats
• Director (dir) compressed into a Shockwave animation file (dcr) for the web
• Windows Audio Video Interleaved Format (avi)
• Macintosh ( quicktime, mov)
• Motion Video ( mpeg, mpg)
• Compuserv ( gif)
• Shockwave (dcr)
• Compression for Director is 75%+ turning a 100k file into a 25k file
Saurabh Gupta, AP-CSE, NIEC
Making Animations that Work
• Use animations carefully so your
screens don‟t become too “busy”
• Animation tools
– Director
– Adobe GOLive
– GIF animators
Saurabh Gupta, AP-CSE, NIEC
Creating Animation • Software helps create objects
such as:
A rolling ball
Saurabh Gupta, AP-CSE, NIEC
Creating Animation • Software helps create objects
such as:
A rolling ball
A bouncing ball
s=1/2gt2
Saurabh Gupta, AP-CSE, NIEC
Bouncing Ball
• Requires a series of rotations
• A knowledge of physics (s= 1/2gt2)
• Ball will uniformly accelerate and
decelerate by squares 1,4,9,16,….
(as Galileo discovered)
(See examples, pp.329-334)
Saurabh Gupta, AP-CSE, NIEC
Creating Animation • Software helps create objects
such as:
A rolling ball
A bouncing ball
•An animated scene
Saurabh Gupta, AP-CSE, NIEC
Overview
• Using video.
• How video works?
• Broadcast video standards.
• Analog video.
• Digital video.
• Video recording and tape formats.
• Shooting and editing video.
• Optimizing video files for CD-ROM.
Saurabh Gupta, AP-CSE, NIEC
Video
• Video is the most recent addition to the
elements of multimedia
• It places the greatest demands on the
computer and memory (using about
108 GB per hour for full motion)
• Often requires additional hardware
(video compression board, audio
board, RAID - Redundant Array of
Independent Disks- for high speed data
transfer) Saurabh Gupta, AP-CSE, NIEC
Using Video
• Carefully planned video can enhance
a presentation (eg. film clip of JFK,
better than an text box of same
message)
• Before adding video to a project, it is
essential to understand the medium,
how to integrate it, its limitations,
and its costs
Saurabh Gupta, AP-CSE, NIEC
Using Digital Video
• Digital video has replaced analog as
the method of choice for making and
delivering video for multimedia.
• Digital video device produces
excellent finished products at a
fraction of the cost of analog.
Saurabh Gupta, AP-CSE, NIEC
Using Digital Video
• Digital video eliminates the image-
degrading analog-to-digital
conversion.
• Many digital video sources exist, but
getting the rights can be difficult,
time-consuming, and expensive.
Saurabh Gupta, AP-CSE, NIEC
Video Clips
• Ways to obtain video
– shoot new film clips with a digital
camcorder
– convert you own video clips to digital
format
– acquire video from an archive - often
very expensive, difficult to obtain
permissions or licensing rights
• Be sure to obtain permission from
anyone you film or for any audio you
use!
Saurabh Gupta, AP-CSE, NIEC
How Video Works
• Light passes from an object through the video camera lens and is converted into an electrical signal by a CCD (charge-coupled device).
• High quality cameras have 3 CCD
• Signal contains 3 channels of color information (red, green, blue) and a synchronization pulse.
Saurabh Gupta, AP-CSE, NIEC
How Video Works
• If each channel of a color signal is
separate it is called RGB ( preferred)
• A single composite of the colors and
sync signal is less precise
• A typical video tape has separate
tracks for audio, video, and control
Saurabh Gupta, AP-CSE, NIEC
How Video Works
• The video signal is magnetically
written to tape by a spinning
recording head following a helical
path
• Audio is recorded on a separate
straight track
• The control track regulates the speed
and keeps the tracks aligned as the
tape plays/records.
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
• NTSC
• PAL
• SECAM
• HDTV
Six different formats
Aspect ratio is 16:9
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
National Television Standards
Committee (NTSC):
– These standards define a method for
encoding information into electronic
signal that creates a television picture.
– It has screen resolution of 525
horizontal scan lines and a scan rate of
30 frames per second.
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
• NTSC- National Television Standards Committee - 1952, (“never the same color”)
• 1 frame = 525 horizontal lines every 1/30 second
• 2 passes - odd/even lines, 60/second
(60 Hz)
• interlacing - to reduce flicker
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
Phase Alternate Line (PAL) and Sequential Color
and Memory (SECAM):
• PAL has a screen resolution of 625 horizontal lines
and a scan rate of 25 frames per second.
• SECAM has a screen resolution of 625 horizontal
lines and is a 50 Hz system.
• SECAM differs from NTSC and PAL color systems in
its basic technology and broadcast method.
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
Advanced Television Systems Committee
(ATSC) Digital Television (DTV):
• This digital standard provides TV stations
with sufficient bandwidth to present four or
five Standard Television (STV) signals or
one High Definition TV (HDTV) signal.
• This standard allows for transmission of
data to computers and for new Advanced
TV (ATV) interactive services.
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards
• Several incompatible standards:
• NTSC (US, Japan, many other
countries)
• PAL - (United Kingdom, parts of
Europe, Australia, South Africa)
• SECAM - (France Russia, few others)
• HDTV - ( US ) - newest technology
Saurabh Gupta, AP-CSE, NIEC
Broadcast Video Standards • HDTV- High Definition Television
now available, allow viewing of
Cinemascope and Panavision movies
with aspect ratio 16:9 ( wider than
high) (See p. 184)
• Twice the resolution, interlaced
format
• Digitized then compressed for
transmission
Saurabh Gupta, AP-CSE, NIEC
Integrating Computers and
Television
• Television video is based on analog
technology and international
broadcast standards
• Computer video is based on digital
technology and other image display
standards
• DVD and HDTV merges the two
Saurabh Gupta, AP-CSE, NIEC
Analog Video – Analog television sets remain the most widely
installed platforms for delivering and viewing video.
– Television sets use composite input. Hence
colors are less pure and less accurate than
computers using RGB component.
– NTSC television uses a limited color palette and
restricted luminance (brightness) levels and
black levels.
Saurabh Gupta, AP-CSE, NIEC
Analog Video
– Some colors generated by a computer that
display fine on a RGB monitor may be
illegal for display on a NTSC TV.
– While producing a multimedia project,
consider whether it will be played on a RGB
monitor or a conventional television set.
Saurabh Gupta, AP-CSE, NIEC
Video Overlay System
• To display analog video (TV) images
on a computer monitor, the signal
must be converted from analog to
digital form ( Where else does this
conversion commonly take place?)
• A special digitizing video overly
board is required for the conversion
• Produces excellent quality, full
screen, full motion video, but costly.
Saurabh Gupta, AP-CSE, NIEC
Video Overlay System
• Many companies use computer based
training (CBT) systems
• These require a computer and monitor
cabled to a TV and video disc player.
• Overlay boards allow the video disc to be
controlled by the computer and display
the images on the computer screen.
Saurabh Gupta, AP-CSE, NIEC
Video Capture Boards
• Video overlay boards can capture or
digitize video frames and play them
back as QuickTime MPEG and AVI
movies.
• Some also include audio input and
sound management to interleave
sound and images
• Some also offer compression and
accelerate digitizing, or support
NTSC video. Saurabh Gupta, AP-CSE, NIEC
Differences Between Computer
and TV Video
• Computer scan refresh rate = 480
lines/sec
• Computer scan is progressive ( non-
interlaced) at 66.67 HZ or higher
• TV scans at 525 (or 625) lines/sec,
with interlacing at a frame rate of 60
Hz
Saurabh Gupta, AP-CSE, NIEC
Interlacing Effects
• The TV electron beam actually
“draws all the odd line, then all the
even lines, interlacing them
• On a computer (RGB) monitor, lines
are painted one pixel thick and are
not interlaced. Displayed on a TV
they “flicker” because they appear in
every other field. To avoid this avoid
very thin lines and elaborate serifs.
Saurabh Gupta, AP-CSE, NIEC
Differences Between Computer
and TV Video
• TV broadcasts an image larger than
the screen so that the “edge” of the
image is against the edge of the
screen. This is called overscan
• Computer images are smaller than
the screen area (called underscan)
and there is a border around the
image
Saurabh Gupta, AP-CSE, NIEC
Differences Between Computer
and TV Video
• When a computer screen is
converted to video the outer edges
do not fit on the TV screen only about
360-480 lines of the computer image
are visible.
• Avoid using the outer 15% of the
screen for graphics, or titles for use
on TV
• Use the safe title area ( See p. 184)
Saurabh Gupta, AP-CSE, NIEC
Video Color
• Color reproduction and display are
also different in TV and computers
monitors
• Computers use RBG component
video and produce more pure color
• NTSC TV uses a limited color palette
and restricted luminance
(brightness) and black levels
Saurabh Gupta, AP-CSE, NIEC
Working with Text and Titles for
Video Productions • Use plain, bold, easily read fonts
• Use light color text on a dark
background
• Avoid color combinations like
yellow/violet, blue/orange which
“vibrate”
• Avoid black or colored text on white
background
Saurabh Gupta, AP-CSE, NIEC
Working with Text and Titles for
Video Productions
• Make lines and graphics at least two pixels wide
• Use parallel lines and boxes sparingly and draw them with thick lines
• Avoid “hot” colors
• Keep graphics and titles in the safe screen area
Saurabh Gupta, AP-CSE, NIEC
Working with Text and Titles for
Video Productions
• Bring titles on slowly and let them
remain on the screen sufficiently
long, fade out
• Avoid “busy” screens- use additional
pages instead
Saurabh Gupta, AP-CSE, NIEC
Digital Video
• Digital video architecture.
• Digital video compression.
Saurabh Gupta, AP-CSE, NIEC
Digital Video Architecture
• Digital video architecture consists of
a format for encoding and playing
back video files by a computer.
• Architecture includes a player that
can recognize and play files created
for that format.
Saurabh Gupta, AP-CSE, NIEC
Digital Video Compression
• Digital video compression schemes or “codecs” ( coder/decoder) is the algorithm used to compress (code) a video for delivery.
• The codec then decodes the compressed video in real-time for fast playback.
• Streaming audio and video starts playback as soon as enough data has transferred to the user‟s computer to sustain this playback.
Saurabh Gupta, AP-CSE, NIEC
Video Compression • To store even a 10 second movie clip
requires the transfer of an enormous
amount of data in a very short time
• 30 seconds of video will fill a 1 GB
hard drive
• Typical hard drives transfer about
1MB/second and CD- ROMs about
600K/second
Saurabh Gupta, AP-CSE, NIEC
Video Compression
• Full motion video requires the
computer to deliver the data at 30
MB/second more than today‟s PCs
and MACs can handle
• Solution- use video compression
algorithms or codecs
• Codecs compress the video for
delivery and then decode it for
playback at rates from 50:1 to 200:1
Saurabh Gupta, AP-CSE, NIEC
Video Compression & Streaming
• Codecs ( such as MPEG, JPEG) use
lossy compression schemes
• Streaming technologies are also
used to provide reasonable quality ,
low-bandwidth on the WEB
• Playback starts as soon as enough
data have been transferred to the
user‟s computer instead of waiting
for the whole file to download
• ( RealAudio and RealVideo software) Saurabh Gupta, AP-CSE, NIEC
MPEG
• Standard developed by the Moving
PIcturesExperts Group for digital
representation of moving pictures
and associated audio
• http://mpeg.org
Saurabh Gupta, AP-CSE, NIEC
Digital Video Compression
• MPEG is a real-time video compression
algorithm. (Moving Picture Experts Group)
• MPEG-4 (1998-1999) includes numerous
multimedia capabilities and is a preferred
standard.
• MPEG-7 (2002) (or Multimedia Content
Description Interface) integrates
information about motion video elements
with their use.
• MPEG –21 under development
Saurabh Gupta, AP-CSE, NIEC
Digital Video
• Video clips can be shot or converted
to digital format and stored on the
hard drive.
• They can be played back without
overlay boards, second monitors or
videodiscs using QuickTime or
Active Movie for Windows
• Analog video can be converted to
digital or now created in digital form
Saurabh Gupta, AP-CSE, NIEC
Video Recording and Tape
Formats
• Composite analog video.
• Component analog video.
• Composite digital.
• Component digital.
• ATSC digital TV.
Saurabh Gupta, AP-CSE, NIEC
Composite Analog Video
• Composite video combines the luminance
and chroma information from the video
signal.
• Composite video produces lowest quality
video and is most susceptible to
generation loss.
• Generation loss is the loss of quality that
occurs while moving from original footage
to editing master to copy.
Saurabh Gupta, AP-CSE, NIEC
Component Analog Video
• Component video separates the luminance and chroma information.
• It improves the quality of the video and decreases generation loss.
• In S-video, color and luminance information are kept on two separate tracks (Y/C) to improve the picture quality.
• Betacam is a new portable professional video format which lays the signal on the tape in three component channels.
Saurabh Gupta, AP-CSE, NIEC
Composite Digital
• Composite digital recording formats
combine the luminance and chroma
information.
• They sample the incoming waveforms and
encode the information in binary (0/1)
digital code.
• It improves color and image resolution
and eliminates generation loss.
Saurabh Gupta, AP-CSE, NIEC
Component Digital
• Component digital formats add the advantages of component signals to digital recording.
• D-1 component digital format is an uncompressed format which has a very high quality image.
• It uses a 19 mm (3/4-inch) tape in order to save data.
• Several other digital component formats are DCT, Digital Betacam, DV format, DVCPRO, and DVCAM formats.
Saurabh Gupta, AP-CSE, NIEC
ATSC Digital TV
• These standards provide for digital
STV and HDTV recordings that can
be broadcast by digital TV
transmitters to digital TV receivers.
• ATSC standards also provide for
enhanced TV bringing the
interactivity of multimedia and the
Web to broadcast television.
Saurabh Gupta, AP-CSE, NIEC
Vaughn’s Law of Multimedia
Minimums
• Your goal is to produce multimedia
that is adequate and does it‟s job but
doesn‟t throw you into bankruptcy.
• Experiment with various levels of
consumer grade equipment
• Professional sound and video
equipment is very expensive
Saurabh Gupta, AP-CSE, NIEC
Recording Formats
• S-VHS and Hi-8 consumer quality
• Component (YUV) - Sony BetacamSP the professional standard for broadcast quality
• Component Digital- a digital version of the Betacam- best format for
graphics > $900,000 and produces 15 minutes of video
• Composite Digital most common >$110,000
Saurabh Gupta, AP-CSE, NIEC
Shooting and Editing Video
• Shooting platform
– use a steady tripod
– or a camera with an electronic image
stabilization feature to avoid “shaky
hand effect”
– or use camera moves and moving
subjects to disguise your lack of
steadiness
Saurabh Gupta, AP-CSE, NIEC
Shooting and Editing Video
• Lighting performance is the main
difference between professional and
consumer camcorders
• Use a simple floodlight kit or natural
daylight to improve the image
• Onboard flood lights can be used as
fill light to illumine faces
Saurabh Gupta, AP-CSE, NIEC
Shooting and Editing Video
• Chroma Key or Blue Screen - popular
technique for making multimedia without
the use of expensive backgrounds
• In shooting against a blue screen, be sure
that the lighting is perfectly even and that
actors are not too close to the screen so
that color “spills” over on them
Saurabh Gupta, AP-CSE, NIEC
Shooting and Editing Video
• Composition
– Avoid wide panoramic shots
– Use close-ups, head and shoulders
– Remember the more a scene changes
the slower the playback will be
– Keep the camera still, let the subject
add the motion by walking, turning...
Saurabh Gupta, AP-CSE, NIEC
Using Video Tapes
• Fast forward new tapes and rewind
them so that the tension is even
(called “packing”)
• Black-stripe the tape by running it
through the recorder with the lens
cap on -eliminates “snowy noise”
• Do not reuse tapes after editing
• Remove break off tab to avoid
overwriting
Saurabh Gupta, AP-CSE, NIEC
Video Hardware Resolution
• Horizontal resolution -the number of lines
of detail the camera can reproduce
• Different from the vertical scan lines on TV
• The lens, and number, size and quality of
the CCDs determine the resolution
• Poor resolution = poor image
Saurabh Gupta, AP-CSE, NIEC
Consumer Grade Equipment
• Mass production at low cost; easier
to use
• Cameras and camcorders that use
HI-8 and S-VHS formats are superior
to 8 mm and VHS systems
• HI-8 is most widely available tape
format and best consumer grade
Saurabh Gupta, AP-CSE, NIEC
Making Tape Copies
• For demo or promo tapes use at least
Super VHS ( HI-8 is best and allow
unlimited copies to be made without
degradation)
• Copying ( dubbing) depends on the
tape format and the quality of the
equipment being used
• Copy in SP mode- faster writing
produces better images
Saurabh Gupta, AP-CSE, NIEC
Video Window Size
• Shrinking a digitized image improves
it perceived sharpness
• ( Also happens when you switch
from 19” to 13” TV)
• The image is crisper because the
scan lines are closer together
Saurabh Gupta, AP-CSE, NIEC
Editing with Consumer VCRs
• Editing with 2 VCRs causes
problems because the two machines
are not in sync
• Editing software, such as Premier, or
After Effects, has become more
commonly used in multimedia
Saurabh Gupta, AP-CSE, NIEC
P*64
• Video telephone conferencing
standard for compressing audio and
motion video images
• Encodes audio and video for
transmission over copper or fiber
optic lines
• Other compression systems are
currently being developed by Kodak,
Sony, etc.
Saurabh Gupta, AP-CSE, NIEC
Optimizing Video files
for CD-ROMs
• CD- ROMs are an excellent
distribution media for multimedia:
inexpensive, store great quantities of
information, with adequate video
transfer rates
• Suitable for QuickTime and AVI file
formats as well as those produced by
Director, etc.
Saurabh Gupta, AP-CSE, NIEC
Optimizing Video files
for CD-ROMs • Limit the synchronization between
video and audio
– AVI interleaves them
– QuickTime files must be “flattened” - to interleave the audio and video
• Use regularly spaced key frames (10 to 15 frames apart)
• Limit the size of the video window- the more data the slower the playback
Saurabh Gupta, AP-CSE, NIEC
Optimizing Video files
for CD-ROMs
• Choose the software compression algorithm carefully
– Sorenson codec is optimized for CD-ROM playback
– Cinepack algorithm, available with AVI and QuickTime, is also optimized for CD-ROM playback
– Use Norton speed Disk to defragment your files before burning the master
Saurabh Gupta, AP-CSE, NIEC
Overview
• Macintosh versus Windows platform.
• Networking Macintosh and Windows
computers.
• Connections.
• Memory.
• Storage devices.
• Input and output devices.
• Communication devices.
Saurabh Gupta, AP-CSE, NIEC
Which Platform Mac or PC?
• Select platform based on
– Personal preference
– Budget constraints
– Project delivery requirements
– Type and content of project materials
– Availability to target audience
Saurabh Gupta, AP-CSE, NIEC
Mac versus Windows
The Macintosh platform:
– Was launched by Apple in 1984.
– Has a good built-in audio and high-quality graphics capability.
– Includes hardware and software for digitizing and editing video and producing DVD discs.
– Makes multimedia project development easier and smoother.
Saurabh Gupta, AP-CSE, NIEC
Mac versus Windows
The Windows platform:
– Is a collection of different vendor-neutral
components that are tied together by the
requirements of the Windows operating
system.
– Initially focused on business computing and
was not suitable for multimedia. However, it is
now easier to find multimedia hardware and
software for Windows as compared to the
Macintosh.
Saurabh Gupta, AP-CSE, NIEC
MAC vs. PC
• Macintosh
• Since 1984 has
been multimedia
• Good built-in
audio
• Easy to learn GUI
PC
• Intended for business
• System beeps and tiny, tinny speaker
• DOS screen- command driven
• Since late 1980‟s provides multimedia
capabilities
Saurabh Gupta, AP-CSE, NIEC
Macintosh Platform
• All Macs can play sound
– Latest include hardware for digitizing
sound
• 8/16/24 bit graphics available
• Can digitize both sound and video
• Requires a mouse
Saurabh Gupta, AP-CSE, NIEC
Macintosh Platform
• Power Mac
– 1994 (RISC) – reduced instruction set computing ( IBM/Motorola)
– 1997 G3 series – clock speeds > 233MHz • Higher performance than existing Pentium
based windows machines
– 2003 G4 series – clock speeds > GHz • Dual processor
• Performance 20 times better than G3
Saurabh Gupta, AP-CSE, NIEC
Windows Multimedia PCs
• MPC Standard- manufacturers
guarantee that software written to
the MPC standard (labeled MPC
compliant) will play on their
machines.
• Three levels of minimum
requirements: MPC1, MPC2, MPC3
Saurabh Gupta, AP-CSE, NIEC
Windows Multimedia PCs
• 1990- Level 1 ( MPC1)
– 16 MHz, 386SX, 2MB RAM, 30 MB drive
– CD-ROM, VGA video ( 16 colors)
– 8 bit audio board, speakers/headphones
– MS Windows with Multimedia Extensions
package
• Not powerful enough to develop Multimedia
• Hardly powerful enough to play it
Saurabh Gupta, AP-CSE, NIEC
Windows Multimedia PCs
• 1993- Level 2 ( MPC2)
– 25 MHz, 486SX, 4MB RAM, 160 MB drive
– 2xCD-ROM, VGA/SVGA video
– 16 bit audio board,
speakers/headphones, microphone
Saurabh Gupta, AP-CSE, NIEC
Windows Multimedia PCs
• 1995- Level 3 (MPC3)
– 75 MHz, Pentium, 8 MB RAM, 540 MB
drive
– 4xCD- ROM, MPG support
– MPEG1 video playback
– Full motion video ( in small window)
with TV quality
– CD quality sound
Saurabh Gupta, AP-CSE, NIEC
Networking
• LANs- local area
networks
• Located within short
distances ( such as a
campus, or building)
• Allow sharing of
resources such as
printers
• Ethernet for cross-
platform development
• WANs- wide area
networks
• Used for long
distances
• More expensive to
install and maintain
• ISPs like AOL, MSN
make it available and
affordable
Saurabh Gupta, AP-CSE, NIEC
Networking Mac and Windows
• Networking is essential for direct
communication and sharing of
resources across platforms.
• Local area network (LAN), wide area
network (WAN), and Internet
connections provide connectivity
and networking capabilities.
Saurabh Gupta, AP-CSE, NIEC
Networking
• In a LAN, workstations are located within a short distance. They are relatively less expensive.
• In a WAN, communication systems span great distances and are typically set up and managed by large corporations. They are expensive to install and maintain.
• A dial-up connection to the Internet through an Internet Service Provider (ISP) also enables communication.
Saurabh Gupta, AP-CSE, NIEC
Networking
• To establish communication between a Macintosh and Windows PC, install Ethernet system and client-server software.
• Ethernet is a method of wiring up computers.
• Client/server software is required for communication and transfer of files.
• Macintosh computers have built-in Ethernet networking, while Windows PCs require an additional Ethernet card.
Saurabh Gupta, AP-CSE, NIEC
Networking
• MACs
• Have ethernet built
in
• Usually run
Appletalk
• Need DAVE to
communicate with
PC
• PCs
• Need ethernet
cards
• Usually run TCP/IP
• Need MACLAN to
communicate with
MAC
Client/server software enables computers to
communicate through an ISP
Saurabh Gupta, AP-CSE, NIEC
Connections
• SCSI ( “scuzzy”) – Small Computer System Interface – lets you add peripherals ( up to 8)
• IDE- connect internal devices
• USB- universal serial bus- “plug and play” and “hot swappable”
• Firewire (IEEE 1394)- supports high bandwidth serial data transfer among multiple computers
Saurabh Gupta, AP-CSE, NIEC
Memory
• Sufficient memory must be allocated for storing and archiving files.
• Memory requirements of a multimedia project depend on the project's content and scope.
• The two types of memory are random access memory (RAM) and read only memory (ROM).
Saurabh Gupta, AP-CSE, NIEC
Memory and Storage Devices
• RAM
• ROM
• Floppy and Hard Disks
• Zip, Jaz and Syquest – Zip – 100MB
– Jaz – 1 GB
• Optical Storage CD, CD-R, etc.)
• DVD (Digital Versatile Disk) upto 1GB – DVD-video
– DVD-ROM
Saurabh Gupta, AP-CSE, NIEC
Input Devices • Keyboards
• Mice and Trackballs
• Touchscreens
• Magnetic Card Encoders and Readers
• Graphic Tablets
• Scanners
• Optical Code Recognition (OCR)Devices
• Infrared remotes
• Voice Recognition Systems
• Digital Cameras
• Lightpens
Saurabh Gupta, AP-CSE, NIEC
Output Hardware
• Audio Devices
• Amplifiers and Speakers
• Monitors
• Video Devices
• Projectors • CRT – cathode ray tube
• LCD – liquid crystal display
• Printers – Injet
– laser
Saurabh Gupta, AP-CSE, NIEC
Communication Devices
• Modems ( Hayes Compatible) v.90
• ISDN – Integrated Services Digital
Network
• DSL-Digital Subscriber Line
• Cable Modems
Saurabh Gupta, AP-CSE, NIEC
Modems
• Modems modulate and de-modulate analog signals.
• They provide connectivity through standard phone lines.
• Modems can be internal or external.
• Modem speed is measured in baud, and the standard modem speed should be at least 56 Kbps.
Saurabh Gupta, AP-CSE, NIEC
ISDN
• ISDN stands for Integrated Services Digital Network.
• It is used for higher transmission speeds by telephone.
• They transfer data at the rate of 128 Kbps.
• ISDN lines are used for networking, Internet access, and audio-video conferencing.
• They are more expensive than the conventional analog lines.
Saurabh Gupta, AP-CSE, NIEC
Cable Modems
• They provide Internet access at
speeds 100 to 1,000 times faster than
a telephone modem, over the same
cable network that supplies the
television signal.
• However, due to noise in the system,
sending rates may be much slower
than receiving rates.
Saurabh Gupta, AP-CSE, NIEC
Summary
• Macintosh and Windows are the two most
common hardware platforms used in
multimedia.
• LANs, WANs, Ethernet, and client-server
software facilitate communication and
connectivity among computers.
• Storage devices include floppy disks, hard
disks, Zip drives, Jaz drives, MO drives,
DVDs, and CD-ROMs.
Saurabh Gupta, AP-CSE, NIEC
Summary
• Input devices include keyboards, mice, trackballs, touchscreens, graphic tablets, scanners, OCR devices, infrared remotes, voice recognition software, and digital cameras.
• Output devices include audio devices, speakers, amplifiers, monitors, video devices, projectors, and printers.
• Communication devices include modems, ISDN lines, and cable modems.
Saurabh Gupta, AP-CSE, NIEC
Basic Tools - Overview
• Authoring system ( Authorware)
• Text Editing, Word Processing Tools ( Word)
• Painting and Drawing Tools
• 2D,3D Modeling and Animation Tools
• Image Editing Tools
• Sound Editing Tools
• Animation, Video, and Digital Movie Tools
• Utilities useful for multimedia
Saurabh Gupta, AP-CSE, NIEC
Text Editing and
Word Processing
• “Each new tool has a learning curve”
• Word Processor ( WORD ) – for basic typing, also allows embedded multimedia elements
• OCR ( optical character recognition) – software which turns bitmapped characters into electronically recognizable text – can be used with scanners – Can be imported into Word document
– BE CAREFUL of COPYRIGHT LAWS!!!!
Saurabh Gupta, AP-CSE, NIEC
Text-based tools
Word processors: – Are powerful applications that include spell
checkers, table formatters, thesaurus, and
pre-built templates for commonly used documents.
– Are used for creating project letters, invoices, and storyboards.
– Allow embedded multimedia elements.
– Microsoft Word and WordPerfect are Word processors.
– Often come bundled in an "Office Suite."
Saurabh Gupta, AP-CSE, NIEC
Text-based Tools
Optical Character Recognition (OCR)
software:
– Converts bitmapped characters into
electronically recognizable ASCII text.
– Makes use of probability and expert
system algorithms.
– Is very accurate and saves time and
effort.
Saurabh Gupta, AP-CSE, NIEC
Graphics Tools •Painting and Drawing Tools
•3-D Modeling Tools
•Image Editing Tools
Saurabh Gupta, AP-CSE, NIEC
Painting and Drawing Tools
• Most graphic programs use bitmapped images since they provide the greatest choice.
• Include the Eyedropper tool, Autotrace tool, and anti-aliasing, airbrushing, blending, and masking functionalities.
• PhotoShop, Fireworks, and Painter are painting software.
• CorelDraw, FreeHand, and Illustrator are drawing software.
Saurabh Gupta, AP-CSE, NIEC
Painting and Drawing Tools
• Painting Software (Photoshop) – can
produce bitmapped images
• Drawing software
(Freehand, Corel Draw or Illustrator)
can produce vector- based line art
easily printed to paper
• Some combine the features of both
Saurabh Gupta, AP-CSE, NIEC
Painting and Drawing Tools
Features include:
– An intuitive graphical user interface.
– Scalable dimensions.
– Multiple undo capability.
– Scalable text font support.
– Support for third-party special effect
plug-ins.
– Layering capability.
Saurabh Gupta, AP-CSE, NIEC
Features of Drawing/Painting
Programs
• Graphical interface
• Scalable dimensions to resize, stretch
• Ability to pour color, pattern in areas
• Ability to paint with pattern and clip art
• Customizable pen, brush, eyedropper
• Support for scalable text fonts
• Zooming and multiple undo‟s
• Object layering
Saurabh Gupta, AP-CSE, NIEC
Bitmapped vs. Vector graphics
• A bitmap is a set of pixels or a grid of dots which are displayed on the computer screen to forma an image
• Bitmapped images are more powerful for rendering fine detail and effects
• Vector images are stored as mathematical equations or algorithms that define the curves, lines and shapes in a picture
• Vector-graphics produced by programs such as FLASH load quickly
Saurabh Gupta, AP-CSE, NIEC
Bitmap vs. Vector Graphics
• Vector images have advantages over
bitmaps:
– Vector images are scalable ( size can be
changed without loss of quality
– Smaller file size usually results in faster
internet downloads
Saurabh Gupta, AP-CSE, NIEC
3-D Modeling Tools
Features include:
– Good color and palette management.
– Multiple dimension windows and
unlimited cameras.
– Lathe and extrude features.
– Ability to drag and drop primitive
shapes, sculpt organic objects.
– Color and texture mapping.
Saurabh Gupta, AP-CSE, NIEC
2D, 3D Modeling and Animation
• MiniCAD can translate 2D into 3D
• Good 3D modeling tools include: – Multiple windows to view from the “camera‟s
perspective”
– Ability to drag and drop into a scene
– Ability to create objects
– Color and texture mapping
– Ability to add realistic effects (fog, shadow..)
– Ability to add special lighting effects
– Ability to draw spline- based paths for animation
Saurabh Gupta, AP-CSE, NIEC
Image-Editing Tools
• Are specialized and powerful tools for enhancing and retouching existing bitmapped images.
• Features include conversion of image-data types and file formats, masking features, employment of virtual memory scheme, etc.
• Support third-party plug-ins.
Saurabh Gupta, AP-CSE, NIEC
Image Editing Tools
• Specialized tools for enhancing and
retouching existing bitmapped images
• Some provide tools of drawing and
painting packages
• Some can create images from scratched
as well as import images from digital
cameras, scanners. Original artwork or
files made with drawing/painting packages
Saurabh Gupta, AP-CSE, NIEC
Features of Image Editing Tools
(Example- Photoshop) –See pp. 95-96 for complete list of features
• Multiple windows
• Conversion of major image formats
• Direct input from scanner, video sources
• Good selection tools for editing
• Good masking tools
• Multiple levels of undo‟s
• Color mapping controls
• Tools to retouch, blur, sharpen, lighten…
• Geometric transformations….
Saurabh Gupta, AP-CSE, NIEC
Common Computer
Graphics Formats
• .bmp - Windows bitmap
• .pic – PC Paint graphics format
• .mac – Macintosh MacPaint format
• .gif ( Graphics Interchange Format) –
common for graphics on the world wide web
• .jpg – JPEG image (Joint Photographic
Experts Group) – platform independent –
used for photos
• .pcd – Kodak‟s Photo CD format
Saurabh Gupta, AP-CSE, NIEC
Common Computer
Graphics Formats
• .pict – Macintosh standard image format
• .png - Portable Network Graphics Format –
approved by W3C to replace the GIF
format for the web
• .tga – targa video capture board format
• .tif ( Tagged image file format (TIFF)
• .wpg – Word Perfect graphics format
Saurabh Gupta, AP-CSE, NIEC
Other Graphics
• Clip Art – extensive clip art libraries
exist on the internet; many have
general categories such as nature,
icons, backgrounds, etc.
• Digitized Pictures – captured from
cameras, videos, etc.
Saurabh Gupta, AP-CSE, NIEC
Sound Editing Tools
• Enables the user to “see” music as well as hear sound.
• This is done by drawing a representation of sound in fine increments.
• Enable the user to create custom system beeps.
• System beeps are pre-packaged sounds that indicate an error, warning or special user activity.
Saurabh Gupta, AP-CSE, NIEC
Sound Editing
• Sound editing for digitized and MIDI sound
let you “see” sound ( as a score or wave
form) as well as hear it.
• Allows you to create sound and special
effects
• Creative Labs Wave Studio often comes
with PC sound boards; Mac users need to
get Sound Edit16 or similar tools
Saurabh Gupta, AP-CSE, NIEC
Sound Objects
• Waveform Audio
• MIDI soundtracks
• Compact disc ( CD) audio
• MP3 files
Saurabh Gupta, AP-CSE, NIEC
Waveform Audio
• Similar to digital images, sounds can
be digitized
• The waveform describes its
frequency, amplitude and harmonics
• Digitized by sampling wave many
times a second and stored as data in
a .wav file
Saurabh Gupta, AP-CSE, NIEC
MIDI
• Stands for
Musical Instrument Digital Interface
• MIDI stores the performance information needed for your sound card to play the music : notes on/off, duration, loud/soft/ timbre/tone and other special effects
• Stored as .mid file
Saurabh Gupta, AP-CSE, NIEC
Audio CD
• Stores up to 75 minutes of high
quality sound
• Sampled at a rate of 44,100 /second
• Samples are 16 bits, with a range of
98dB ( from a quiet whisper to a loud
scream)
Saurabh Gupta, AP-CSE, NIEC
MP3 Format
• Stands for MPEG Audio Layer 3
• Audio file format that uses a code to encode (compress) and decode
(decompress) recorded music into smaller files to transmit across the internet
• Software which creates MP3 files from an audio CD is called a ripper
Saurabh Gupta, AP-CSE, NIEC
Animation, Video, and Digital
Movie Tools
• Animation is a sequence of bitmapped graphic scenes or frames, rapidly played back.
• Animations can be made within some authoring systems by moving objects or sprites to simulate motion.
• Moviemaking tools take advantage of QuickTime and AVI formats to create, edit, and present digitized motion video segments.
Saurabh Gupta, AP-CSE, NIEC
Animation, Video, and Digital
Movie Tools
• Digital video editing and playback require
a large amount of free disk space.
• When working with digital video, it is
necessary to defragment and optimize the
disk before recording and playing back
movie files.
• It is necessary to compress movie files
before delivery.
Saurabh Gupta, AP-CSE, NIEC
Animation, Video, and Digital
Movie Tools
• Compression ratio is the size of the
original image divided by the size of the
compressed image.
• Compression can by lossy or lossless.
• Lossy schemes ignore picture information
the viewer may not miss.
• Lossless schemes preserve the original
data precisely.
Saurabh Gupta, AP-CSE, NIEC
Animation
• Frame Animation
• Vector animation
• Computational animation
• Morphing
Saurabh Gupta, AP-CSE, NIEC
Animation, Video and Digital
Movie Tools
• Animations are often sequences of
bitmapped graphics( frames), which are played back rapidly ( frame –oriented)
• Authoring systems can create animation by rapidly changing the location of objects or sprites (object-oriented or vector animation.)
Saurabh Gupta, AP-CSE, NIEC
Animation
• Vector animation varies the
beginning, length and direction
parameters for the lines that define
an image, such as in FLASH
• Computational animation allows you
to move object across the screen by
changing their x,y coordinates
Saurabh Gupta, AP-CSE, NIEC
Morphing
• An animation technique that allows
you to blend two still images creating
a sequence of in-between images
that show one image
metamorphosing into the other ( for
example a race car changing into a
running tiger…)
Saurabh Gupta, AP-CSE, NIEC
Animation, Video and Digital
Movie Tools
• Special hardware (video capture boards)
are often needed to convert analog signal
(camera) to digital (computer) – more
recently digital cameras and camcorders
have become available
• (Adobe Premiere ) allows you to edit video
clips assembled from camera videotape,
scanned images, digitized audio or MIDI
files
Saurabh Gupta, AP-CSE, NIEC
Video Formats
QuickTime:
– Is a software-based architecture for integrating
sound, text, animation, and video on Macintosh
and Windows platform.
– Is an extensible system for multimedia delivery.
– Can deliver 3-D animations, virtual reality, and
streaming audio-video on the Web.
– The three QuickTime elements are Movie file
format, Media Abstraction Layer, and Media
services.
Saurabh Gupta, AP-CSE, NIEC
Video Formats
QuickTime (continued):
– Includes built-in support for ten
different media types.
– Offers a comprehensive set of services.
– Allows embedded commands in HTML
documents.
Saurabh Gupta, AP-CSE, NIEC
Video Formats
Audio Video Interleaved (AVI):
– Is a Microsoft-developed format for playing full-motion interleaved video and audio sequences in Windows.
– Does not require specialized hardware.
– Is an inextensible, open environment.
– Lacks serious video editing features.
– The OpenDML format was developed to make AVI more functional.
Saurabh Gupta, AP-CSE, NIEC
Video Formats
• QuickTime and Audio Video Interleaved
(AVI) formats support special algorithms,
provide a methodology for interleaving,
and allow organized streaming of data
from disk into memory.
• Digital Versatile Disc (DVD) is a hardware
format that uses laser light to store and
read digital information.
Saurabh Gupta, AP-CSE, NIEC
Common Video Formats
• QuickTime from Apple for both Mac and
PC
• AVI – MS Audio Video Interleaved for
Windows
• Both blend (interleave) audio and video
• Neither is currently capable of producing
full screen images at 30 frames/second
(TV standard)
Saurabh Gupta, AP-CSE, NIEC
QuickTime • Multitrack recorder with almost
unlimited range of tracks.
• Supports digitized video and sound,
computer animations, MIDI data, and
external devices ( CD-ROM players,
videodisks, etc.)
• Provides imbedded support and
services for 10 media types ( p.101)
• Provides embedded HTML
commands
Saurabh Gupta, AP-CSE, NIEC
QuickTime
• Integrates sound, text, animation and
video
• Can be used on the internet to
deliver multimedia through plug-ins
• Provides the foundation for the new
MPEG-4 Multimedia format for the
web
Saurabh Gupta, AP-CSE, NIEC
QuickTime
• Movie file format- provides a standard method for storing audio, video, text
• Media Abstraction Layer – describes how your computer should access the media
• Media Services- includes built-in support for different media types and offers services for: timing, synchronization, data compression, format conversion, audio mixing, special effects, media capture,
movie controllers, etc. ( See p.114-115)
Saurabh Gupta, AP-CSE, NIEC
Some QuickTime Embedded
Commands for HTML
• Powerful commands for controlling a QuickTime file can be embedded right in the HTML code: – AUTOPLAY- starts movie automatically
– BGCOLOR – sets background color for movie
– HEIGHT and WIDTH specifies size of movie in
web page
– LOOP- plays movie in continuous loop
– VOLUME- sets default playback volume
– HIDDEN – plays sound only
Saurabh Gupta, AP-CSE, NIEC
Windows Video
• Media Control Interface ( MCI) provides a
uniform command interface for managing
audio and video that interleaves them
together in the file called AVI – (audio
video interleaved).
• AVI plays about 15 frames/second in a
small window
• Lacks features needed for serious
video/sound editing
Saurabh Gupta, AP-CSE, NIEC
Windows Video Features
• Playback from hard disk or CD-ROM
• Uses limited amount of memory
• Quick loading and playing
• Video compression available
• Some tools VidCap and VidEdit to
capture and edit video ( see p. 116)
Saurabh Gupta, AP-CSE, NIEC
Movie Editors
• With desktop editing software and video digitizing boards you can digitize video clips, edit the clip, add special effects and titles, mix sound tracks and save the finished product on magnetic or optical media
• Reuires an enormous of hard drive space
• Software : Adobe Premiere
• Digitizing Boards: Targa, Creative Labs
• ( see p. 117)
Saurabh Gupta, AP-CSE, NIEC
Movie Compression
• Image compression algorithms are essential to deliver motion video and audio
• Massive amounts of data are needed to display a new screen image every 1/30 second
• Compression ratio of at least 5:1 needed to transmit over phone lines
Saurabh Gupta, AP-CSE, NIEC
Movie Compression
• Compression ratio- size of the
original image divided by the size of the compressed image; usually only the part of the image that changes form image to image ( delta), The higher the ratio, the lower the image quality
• Image quality – Lossy- ignores picture information that the
viewer may not miss
– Lostless- preserves the original data precisely
• Compression/decompression speed – ideally as fast as possible
Saurabh Gupta, AP-CSE, NIEC
Utilities Useful For Multimedia
• Screen grabber- allows you to grab all or
part of a screen display and put it into an
authoring system or image editor. (Can
use the clipboard)
• Format converters – for converting source
materials form UNIX, MAC, etc.
• GIF animator – to create animated GIFs,
available on the web, ( public-domain)
Saurabh Gupta, AP-CSE, NIEC
Summary
• Word processors and OCR software are
used to handle text in multimedia.
• Painting and drawing tools, 3-D modeling
tools, and image editing tools manipulate
the graphical content of the project.
• QuickTime for Macintosh and AVI for
Windows are the two most widely used
video formats.
Saurabh Gupta, AP-CSE, NIEC