Programming Question

‫ر‬‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Information Technology
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 2
THE MULTIMEDIA REVOLUTION
Contents
1. Multimedia Defined
2. Forms of Multimedia
3. Multimedia Visionaries
4. Multimedia Today- The Revolution continues
Weekly Learning Outcomes
1. Explain how computing has generated a multimedia
revolution.
2. Define interactive and non-interactive multimedia.
3. Identify the visionaries of multimedia computing and the
effects of their contributions.
Required Reading
Chapter 1: “The Multimedia Revolution”, Savage T., & Vogel, K. (2014). An Introduction to
Digital Multimedia. (2 ed). Burlington: Jones and Barlett Learning. ISBN: 144968839
(print), 9781449688394 (e-text).
Recommended Reading
1. “The Future of Virtual Reality Is Inside Your Smartphone”
https://www.wired.com/2015/03/future-virtual-reality-inside-smartphone/
1. Multimedia Defined
Multimedia Defined
Contemporary Multimedia is the development, integration, and
delivery of any combination of text, graphics, animation, sound or
video through a digital processing device.
2. Forms of Multimedia
Forms of Multimedia
• Non-interactive
• User is a observer of information.
• User has no control over the flow of information.
• Developer establishes the sequence of media elements and how they are
presented.
Examples include:
• Information kiosks
• Digital animations.
Forms of Multimedia
• Interactive
• User is a participant in the flow of information.
• Basic interactivity
• Includes menu and button options to access content.
• Adaptive or Intellimedia
• Adapt the information flow to the needs or interests of the users.
• Immersive
• Draws users into an alternate world.
3. Multimedia Visionaries
FROM ANALOG TO DIGITAL: VISIONS OF THE FUTURE
VANNEVAR BUSH (1890 – 1974)
Memex I -1945
A hypothetical machine to make the work of scientists more effective
and efficient in grasping the “growing mountain of research.” (As We May
Think, 1945)
Memex I Features
• Massive storage capacity.
• Multimedia input devices such as “vocoder” and “cyclops camera.”
• Automatic mathematical calculations and logical reasoning.
• New method to store and access information by associations.
VANNEVAR BUSH (1890 – 1974)
Memex II -1959
Extended the original proposals of Memex I by considering new
technical developments such as Magnetic tape, Transistor & Digital
computer.
Memex II Features
• Professionally maintained associational databases delivered by tape or
facsimile.
• Trails would be color-coded to reflect age and reinforced by repetitive
use.
• Combined with a digital computer, Bush believed the Memex II could
learn from experience and even demonstrate a form of judgment.
ALAN TURING (1912-1954)
• Proposed an abstract machine known as the “Turing Machine.”
• The “machine” was a means of defining an “effective procedure.”
• The imaginary device had three components:
• An infinitely long tape consisting of single row of squares
• A read/write head that moved along the tape one square at a
time
• A set of instructions.
TURING MACHINES
• Single Purpose “Turing Machine.”
• Can carry out a specific set of instructions or “effective procedure.”
• “Universal Turing Machine” (UTM).
• Can accept a description of a single purpose machine and imitate
it’s behavior.
• Implication of the UTM:
If we can think of a way to do something, the computer can do it.
DOUGLAS ENGELBART
• Proposed practical applications of computers beyond the normal
mathematical and sorting functions.
• Developed innovations for human-computer interactivity in the NLS
(oNLineSystem). These included:
• Mouse
• Multiple screen areas for text editing
• Email.
THEODORE NELSON
• Coined terms hypertext and hypermedia.
• Hypertext: interactive text linked to other textual information.
• Hypermedia: extends interactive linking to other media
• Initiated Xanadu Project:
• A dynamic, expanding, hypertext library available to everyone.
• Supported collaborative editing, tracking changes, crediting, and
rewarding contributors.
ALAN KAY
• Proposed a computer design that supported the ways people perceive,
learn, and create.
• Dynabook: designed as a personal computer.
• Tied to the mind and interests of the user.
• A “modeless” multimedia computer.
• Users could move between graphics, sound, text, animation seamlessly.
• Introduced Graphical User Interface (GUI) as an intuitive interface for
the Dynabook.
STEVE JOBS (1955-2011)
• Founded Apple in 1976 with Steve Wozniak.
• Macintosh computer introduced in 1984.
• Graphical desktop and Icons provide user interface.
• First mass produced computer with built in sound support.
• Multimedia computing became the standard for modern
computers.
TIM BERNERS-LEE
• Developed a decentralized information system of “nodes” linked
together for easy access across a network.
• Nodes could be any form of media.
• Anyone could add nodes.
• No centralized control over servers, documents or links.
WWW & MULTIMEDIA COMPUTING
• Basic components of WWW:
• Server computer
• Client computer
• Browser software
• HTML scripting language.
• Solved cross-platform compatibility problem.
• Supported distribution of media beyond the capacity of CD-ROM
storage.
• Allowed instant distribution and inexpensive media creation.
4. Multimedia Today- The Revolution continues
MULTIMEDIA VISIONARIES
• First Generation
• Alan Turing
• Vannevar Bush
• Second Generation
• Douglas Engelbart
• Theodore Nelson
• Alan Kay
• Steve Jobs
• Tim Berners-Lee
• Next Generation
• Current innovators of multimedia
THE REVOLUTION CONTINUES
• Factors influencing the revolution:
• Technical breakthroughs in hardware and software.
• Integration of computers with other devices.
• Digital merger of disparate technologies and industries.
• Further development of wireless communications & mobile
devices.
• Expansion of creative opportunity.
WRAP UP
• Definition of contemporary multimedia.
• Expressions of multimedia.
• Visionaries who contributed to development of digital multimedia.
• Potential of digital media.
• The analog-to-digital revolution.
KEY TERM CHECK UP
Main Reference
1. Chapter 1: “The Multimedia Revolution”, Savage T., &
Vogel, K. (2014). An Introduction to Digital Multimedia. (2
ed). Burlington: Jones and Barlett Learning. ISBN:
144968839 (print), 9781449688394 (e-text).
Thank You
‫ر‬
‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Computer Science
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 2
Digital Data
Contents
1. Elements of digital media
2. Digital codes.
3. Digital files.
4. Digitization process.
5. Compression for digital media.
6. Advantages of digital media.
7. Challenges of digital media.
Weekly Learning Outcomes
1. Explain
the
relationship
among
symbol,
data
and
information.
2. Identify the main differences between analog and digital
video.
Required Reading
Chapter 2 “Digital Data”, Savage T., & Vogel, K. (2014). An Introduction to Digital
Multimedia. (2 ed). Burlington: Jones and Barlett Learning. ISBN: 144968839 (print),
9781449688394 (e-text)
Recommended Reading
1. “The Advantages and Disadvantages of Analogue and Digital Audio”
http://www.planetoftunes.com/digital-audio/pros-and-cons-of-analogue-and-digitalaudio.php
CODING DIGITAL INFORMATION
• Symbols represent something else.
• Organized and understood by a conventional standard.
• Data are the givens of experience.
• Measurements, facts, observations.
• Information is data made useful, interpreted, and applied to produce
understanding.
7
YOU DECIDE: data or information?
People who are 30 years old, pay $30 to run
30 miles in 30 degree weather for a charity
benefit.
Age = 30 yrs.
Temperature = 30 degrees
Distance = 30 mi.
Cost = $30
8
ANALOG vs. DIGITAL DATA
• Analog data varies continuously.
• Digital data consists of separate, discrete units.
Wind mill motion.
Hour glass to tell time.
Numbers
1, 2, 3, 4
YOU DECIDE: Analog or Digital Data?
9
DIGITAL DATA
• Digit = number.
• Binary digit (bit) = 0 or 1.
• Bits are the symbols to encode digital data.
• Digital encoding assigns bits to data items.
Letter A
Number 5
0100 0001
0011 0101
More bits in the code, means more distinct items to encode.
10
BUILDING DIGITAL CODES
• Number of distinct bit combinations that can be produced is given by
n.
the formula 2
• n = number of bits used in the code.
• Adding 1 to the power doubles the number of distinct data items that
can be encoded.
21
22
23
24
2 items
4 items
8 items
16 items
25
26
27
28
Complete the table to identify the number of distinct items
5, 6, 7,
8.
represented by 2 2 2 and 2
11
COMMON CODES
• ASCII, a 7 bit code.
• 128 letters, numbers, and symbols in English language.
• ASCII-8, an 8 bit code.
• 256 letters, numbers, and symbols in English language.
• Unicode, a 16 bit code.
• Over 65,000 different characters.
• 24-bit color.
• Displays the full range a human eye can perceive.
• 16-bit sound.
• Plays the full decibel range the human ear can perceive.
12
DIGITAL FILES
• A container for binary codes.
• File formats define how instructions and data are encoded in the file.
• Sample formats that define data differently:
• Word file format
• Acrobat file format
• Media player file format.
13
ALL ABOUT FILES
• File size
• Measured in units of bytes.
• Kilo Bytes, Mega Bytes, Giga Bytes.
• File extensions
• Series of letters to designate the file format.
• .fla, .exe, .rtf, .jpg
• File compatibility
• Ability to use the file in a different platform of hardware and software.
14
FILE TYPES
• Program files
• Contain executable instructions.
• Data files
• Can hold text, images, sounds, video, animation.
15
DATA FILE COMPATIBILITY
• Cross-platform compatible files.
• Open and use on any computer hardware and software configuration.
• Files that are native or specialized to the application that created the
data file.
• Require source application to open the file.
16
FILE MAINTENANCE
• Data loss and destruction impacts multimedia project completion.
• Effective file maintenance involves:
• Identification
• Categorization
• Preservation.
17
DIGITIZATION
ANALOG TO DIGITAL CONVERSION.
18
SAMPLING ANALOG DATA
Sampling analyzes a small portion of the analog source and converts it
to digital code.
19
SAMPLE QUALITY
• Factors that influence sample quality
• Sample Resolution.
• Number of bits used to represent digital sample.
• Quantization is process of rounding off the value of a sample to the nearest available
digital code.
• Sample Rate.
• Number of samples taken in a given unit of time (sounds) or space (images).
• Spatial resolution describes sample rate in image files.
20
YOU DECIDE … sample resolution
Which image and sound sample will have better quality?
Image
Sound
8 bits / sample
8 bits / sample
24 bits / sample
16 bits / sample
Which image uses fewer bits to describe the color sample?
21
YOU DECIDE … sample rate
Which image and sound sample will have better quality? Why?
Image
Sound
72 pixels / inch
11 kHz
300 pixels / inch
44 kHz
Which image has higher spatial resolution?
50ppi
300ppi
22
DIGITAL ENCODING
• Description-based encoding
• A detailed representation of the discrete elements that comprise the media.
• Command-based encoding
• A set of instructions the computer follows to produce the digital media.
23
MEDIA ENCODING COMPARED
Description
Command
Advantages
Represent natural scenes and
File sizes are small.
sounds.
Supports detailed editing.
Large file sizes.
Lose quality if enlarged.
Scaled without distortion.
Limitations
Not appropriate for detailed photographs
and natural sounds.
Requires knowledge of music and vector
image creation.
24
FILE COMPRESSION
• Process of re-encoding digital data to reduce file size.
• Codec: a program to compress a file into a smaller size and
decompress it into a usable form.
25
MAJOR TYPES OF COMPRESSION
• Lossy
• Number of bits is reduced and some data is lost.
• Lossy strategies include MP3 and JPEG compression.
• Lossless
• Efficient encoding reduces file size without loss of original data.
• Lossless strategies include RLE and GIF compression.
26
YOU DECIDE… Lossy or Lossless
Choose a compression strategy best suited for:
1.
2.
3.
4.
5.
Photograph of sailboat on ocean.
Journal article explaining nanotechnology.
1812 Overture by New York Philharmonic Orchestra.
Database of student names and addresses.
Video of hot air balloon flying over a cornfield.
27
ERROR DETECTION &
CORRECTION
• Digital bits may be lost during transmission or damaged on storage
media.
• CDs get scratched.
• Communication lines have interference.
• Strategies to preserve data vary.
• Parity bits help detect an error during transmission.
• CDs include redundant data to replace data when an error occurs.
28
DIGITAL INFORMATION —
ADVANTAGES
• Reproduction without generation decay.
• Editing and re-editing much easier than with analog
media.
• Integration of media using cut, copy, paste more
efficient.
• Distribution over Internet – nearly everyone can be
reached by anyone else.
29
DIGITAL INFORMATION —
CHALLENGES
• File sizes are large.
• Digital media is processor intensive.
• Absence of media standards renders data files incompatible.
• Some media requires high bandwidth to distribute on networks.
• Concern for longevity and future accessibility of digital data.
30
WRAP UP
• Analog vs. Digital data.
• Symbols and binary code.
• Data vs. Information.
• Files as containers.
• Digitization process.
• Description- vs. Command-based media.
• Compression strategies.
• Error detection & correction.
• Advantages & Challenges of digital data.
31
KEY TERM CHECK UP
Analog data
ASCII
ASCII-8
Bandwidth
Bit
Bitmapped image
Byte
Codec
Command-based
Compression
Convent ion
Data
Data file
Description-based
Digital data
Digital encod ing
Digitization
Effective code
Efficient code
Extended ASCII
File compatibility
File conversion
File extension
File format
Generat ion decay
Gigabyte
Incompatible
Infor mation
Kilobyte
Lossless compression
Lossy co mpression
Megabyte
MP3
Native file format
Parity bit
Platform
Program file
Quant ization
RLE
Sample rate
Sample resolution
Sampled sound
Sampling
Spatial resolution
Symbol
Terabyte
Unicode
Main Reference
1. Chapter 2 “The Multimedia Revolution”, Savage T., &
Vogel, K. (2014). An Introduction to Digital Multimedia. (2
ed). Burlington: Jones and Barlett Learning. ISBN:
144968839 (print), 9781449688394 (e-text)
Thank You
‫ر‬
‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Information Technology
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 3
Computer Hardware
Contents
1. Components of a Computer System
2. Types of a Computer System
3. Computer Platforms
4. Hardware Basics
Weekly Learning Outcomes
1. Identify the components and various types of computer
systems.
2. Explain the functions and components of the central
processing unit (CPU), system board, and hardware interface.
3. Identify the main categories of computer hardware and
explain their function. Summarize the advantages and
disadvantages of the CLV method of data storage.
Required Reading
Chapter 3: “Computer Hardware ”, Savage T., & Vogel, K. (2014). An Introduction to
Digital Multimedia. (2 ed). Burlington: Jones and Barlett Learning. ISBN: 144968839
(print), 9781449688394 (e-text).
Recommended Reading
“What is a CPU and What Does It Do? Technology Explained”
https://www.makeuseof.com/tag/cpu-technology-explained/
1. Components of a Computer System
COMPUTER SYSTEMS
• An integrated set of hardware and software designed to process data
and produce a meaningful result.
• Basic functions:
• Input
• Processing
• Storage
• Output
• Transmission.
1. Types of a Computer System
Types of Computer Systems
• Supercomputer.
• Offers the fastest processing speeds and performs the most
complex calculations.
• Mainframe computer.
• Provides multi-user computing to large organizations for tasks such
as managing extensive databases, financial transactions, and
communications.
• Personal computer.
• Provides computing to a single user performing multiple tasks.
3. Computer Platforms
Computer Platform
• Platform is a combination of hardware and operating system.
• Windows/PC platform.
• Macintosh platform.
• Mobile Computing platform.
• Cross-platform compatibility.
• Ability of an application to run on different hardware and operating
systems.
• Adobe’s Acrobat .pdf files can be opened on Windows or Mac
OS based computers.
• The WWW provides a cross-platform computing experience.
4. Hardware Basics
SYSTEM UNIT
• Contains the components used to electronically process and store
data.
• Central Processing Unit.
• Primary memory.
• Expansion slots.
• System board circuitry.
CENTRAL PROCESSING UNIT (CPU)
• Consists of millions of integrated transistors that execute program
instructions and manipulate data.
• Sets of transistors include:
• Control Unit
• Arithmetic Logic Unit
• Registers
• Cache
• Processing data and instructions is systematically
executed in a machine cycle.
View IT
• Four steps in the cycle: Fetch , Decode , Execute , Store. Intel explains
the future for
transistors on
the CPU.
CPU FEATURES
• Clock speed
• Rate the CPU carries out basic instructions.
• Measured in megahertz (MHz) or gigahertz (GHz).
• Word size
• Number of bits the processor can manipulate in one machine cycle.
• 64 bit processor can execute more data than a 32 bit processor.
• Bus width
• The width of the electronic pathway that moves data and
instructions to the processor.
• A bus 64 bits wide carries more data than a bus 16 bits wide.
CPU FEATURES
• Pipelining
• Method to increase processing speed by launching more than one
instruction in a single machine cycle.
• RISC
• Reduced Instruction Set Computer chips eliminate complex
embedded microcode.
• Multi-processing
• Combination of multiple processors to execute instructions
simultaneously.
APPROCHES TO MULTIPROCESSING
• Multiple processors
• CPU + graphics co-processor.
• Multi-core processors
• Two or more logic cores on a single CPU chip to execute different
tasks.
• Parallel processing
• Linking multiple processors together to operate simultaneously on
the same task.
PRIMARY MEMORY
• Electronic storage locations for data and instructions directly
addressed by the CPU.
• Random Access Memory (RAM)
• Volatile storage area for operating system, software applications,
and user data.
• Capacities are measured in megabytes or gigabytes on personal
computers.
• Read Only Memory (ROM)
• Non-volatile electronic storage for frequently used instructions
such as the computer’s boot sequence.
CACHE MEMORY
• High speed electronic storage to optimize the performance of the CPU.
• Reduces time to fetch data and instructions from RAM storage.
• Level 1 or Primary Cache stores data and instructions on the CPU chip.
• Level 2 Cache positioned between the CPU and RAM.
• Capacities of cache vary.
• Total amounts are not part of RAM capacity.
SYSTEM BOARD
• Electronic circuit board at the base of the system unit.
• Manages flow of electronic bits to:
• CPU
• RAM
• Expansion slots
• Video card
• Analog – Digital converters
• I/O interface ports.
HARDWARE INTERFACE – INTERFACE PORT
• Point of union between the system board and peripheral devices.
Data flows to the system board in
• Parallel transmission or
• Serial transmission
• Ports are external to the system unit.
• Peripherals are plugged into the ports.
• Common ports include:
• VGA or SVGA
• USB
• IEEE 1394 (FireWire)
• Thunderbolt
• Audio input/output
• Network port.
USB, Firewire, & Thunderbolt
• Offers Plug and Play performance.
• Supports a daisy-chain bus of multiple devices.
• Accepted on PCs and Macs.
• Has hot-swappable capability.
• Powered through the interface port.
• No more “wall warts.”
• Thunderbolt advantages:
• Higher transfer rates
• Eliminates need for separate video port
• Increases power to peripheral devices.
PERIPHERAL DEVICES
• Hardware components to input, output, store data and applications
for the processor.
• With the miniaturization of today’s mobile computing devices, the
peripherals may not seem so distant from the system processor.
SECONDARY STORAGE
• Holds data and instructions outside the system unit for long periods of
time.
• Advantages over primary storage:
• Nonvolatile storage
• Expandable
• Portable
• Inexpensive.
•
Options include magnetic, optical, solid-state storage.
SECONDARY STORAGE
• Five Main Uses
• Saving data during edit process.
Storage Devices
• Backup data and applications.
Hard drive
• Distribute data and applications.
Portable hard drive
• Transport data and applications.
• Archive data and applications.
Zip drive
Flash or thumb drive
CD drive
DVD drive
Magnetic tape drive
MAGNETIC STORAGE
• Bits are stored in magnetic form on disk platters or magnetic tape.
• Data stored in addressable tracks and sectors defined by the operating
system.
• Track — circular paths
• Sector — pie shaped logical divisions of the track.
• Hard Drives contain rigid platters mounted on a spindle.
• Motor rotates the platters.
• Access arm with read/write head
moves between the platters.
• Data is stored on top and
bottom of each platter.
HARD DRIVE PERFORMANCE
• Storage capacity
• Measured in gigabytes or terabytes.
• Access time
• Measured in milliseconds, the time to locate data on the platter.
• Transfer rate
• Measured in bytes, the speed of data transfer from the platter to RAM.
MAGNETIC OPTIONS
• Fixed internal hard drive.
• Portable hard drive.
• Cartridge drive.
• RAID drive.
• Magnetic tape drive.
MAGNETIC STORAGE
• Benefits:
• Large storage capacity
• Fast access to data
• Economical.
• Challenges:
• Limited durability
• Easily damaged.
FYI:
The projected cost
of a gigabyte of
magnetic storage in
2016 is .01 cents.
OPTICAL STORAGE – LASER BEAMS
• Compact Disc (CD) first used to replace vinyl records in music industry.
• Stored digital music for permanent, high fidelity recordings.
• Capacity set at 74 minutes of digital audio.
• Laser Beams – Amplified light energy.
• When focused on a shiny surface, the beam reflects
back to a photo detector.
• Disc surface is “stamped” with pits and lands.
• Pits — indentations on surface.
• Land — flat area on surface.
• Digital code is read as variations in the reflection intensity.
FYI:
Disc refers to
optical
storage.
Disk denotes
magnetic
storage.
LASER ADVANTAGES
• High capacity storage.
• Pits = .83 microns long and .5 microns wide.
• Data stored in a continuous spiral from inside to outside edge of disc.
• Durable data.
• Pits and lands are pressed into a platter and coated with lacquer material.
• Data is encoded with error detection/correction to prevent damaged data.
OPTICAL RECORDING
• Data is organized in:
• Tracks — addressing scheme on CD.
• Frame — physical format of the data.
• 58 frames form a sector on CD-ROM or 2048 bytes of data code.
• Sessions — single recorded segment on CD.
• Standard physical size.
• 120 mm, 15mm center hole, 1.2 mm thick.
• Led to rapid development of drives to accept all CD formats.
• CD-DA (Digital Audio format).
• CD-ROM (Read-Only format).
• CD-R (Recordable format).
• CD-RW (Re-Writable format).
OPTICAL DRIVE
• Laser head moves along rails to position the laser lens.
• Light reflects back to a photo detector.
• Motor spins the disc.
• Data is read using:
• CLV — Constant Linear Velocity
• CAV — Constant Angular Velocity.
• Optical storage that uses:
• More precise laser light
• Multi-layer storage
• New video compression methods
• Improved error detection and correction.
DIGITAL VERSATILE DISC (DVD) FEATURES
• Result.
• Higher storage capacity than compact disc
• 650MB on CD (74 minutes of music)
• 17GB on DVD (8 hrs of video).
• More precise laser beam reads smaller pits.
• .40 microns wide vs .83 microns on CD
• Smaller pits = more data capacity.
• Multi layer storage.
• Two reflective layers per side
• Each layer stores 4.7GB data.
FYI: Laser
Wavelength
compared.
CD = 780
nanometers.
DVD = 650
nanometers.
Blu-ray = 405
nanometers
DIGITAL VERSATILE DISC (DVD) FEATURES
• MPEG2 compression.
• Compresses video at 40:1 ratio without compromising video quality.
• Improved error detection/correction.
• CDs use 33% storage for ECC/EDC (error detection and correction).
• DVDs reduce this to 13% of the storage.
• Standards vary by player and data.
• DVD recordable formats:
• DVD-R: compatible with most players & drives
• DVD-RW: playable in many DVD drives and players
• DVD-RAM: Removable storage for computers.
BLUE RAY : NEXT GENERATION
• Optical storage based on blu-ray laser.
• Shorter wavelength (405nm).
• Massive storage capacity.
• Single layer can store 27GB of data.
• Can store 2 hours of high-definition video or
• 13 hours of standard video.
• Dual layer stores 50GB of data.
• Currently used for recording high definition video and PlayStation 3
games.
SOLID-STATE STORAGE
• Computer storage with no moving parts.
• Devices are based on flash memory technology.
• Contains a grid of cells, each with two transistors separated by a thin layer of
insulating oxide.
• The insulating oxide layer preserves information with no need of external
power.
• Benefits:
• Lightweight
• Small
• Low power requirements
• More durable than devices with movable parts.
SOLID-STATE STORAGE
• Disadvantages:
• More expensive than magnetic
storage
• Limited capacity
• Limited life expectancy.
FYI:
Labels for solid state
storage devices
include:
•USB drive
•Flash drive
•Thumb drive
•Memory stick
STORAGE IN THE CLOUD
• The “cloud” is a metaphor for a network server generally accessed via
the Internet.
• Users maintain accounts to store, maintain, and manage data remotely.
• Benefits of networked storage include:
• Portability
• Ubiquitous access.
• Challenges include:
• Security and reliability of the server.
• Access to data is dependent on the performance of a remote server and
network connections.
SECONDARY STORAGE & Future of Digital Data
• Practical issues surrounding the migration of data to secondary
storage include:
• Effective and efficient data management.
• Enduring file formats over the years.
• Ability to access the data on the storage media
• Hardware requirements
• Software dependence.
• Data longevity.
INPUT DEVICES
• Capture and transmit data and instructions to the system using for
processing and storage.
• Categories:
• Keyboard
• Pointing devices
• Scanning devices
• Image capture
• Audio capture.
• Keyboard.
• Capture user text and commands.
INPUT DEVICES
• Pointing device.
• Relies on graphic interface to click or select the input.
• Devices include:
• Fingers
• Mouse
• Pointing stick
• Stylus
• Touch screens
• Touch pads
• Trackball.
FYI:
The Wii Remote is
also a pointing
device for the
popular game
console.
INPUT DEVICES : SCANNER
• Captures text or graphics using a light-sensing device called a ChargeCoupled Device (CCD).
• Types of scanners include:
• Flat bed
• Hand held
• Sheet fed
• Slide.
• Scanner quality depends on:
• Spatial resolution
• Color resolution (bit depth).
SCANNER SETTINGS
• Spatial Resolution (dpi).
• Depends on use of image.
• 72 dpi for computer display.
• 300 dpi for printer output.
• Color resolution (bit depth).
• 8 bit setting confines color range to 256.
• Grayscale setting uses black, white and shades of gray.
• Scaling.
• Set the size larger or smaller before the scan.
• Tonal quality.
• Adjust brightness and contrast based on preview of scan.
OCR
• Optical Character Recognition is a process that converts printed text
into an editable word processed digital file.
• OCR software analyzes the image of a character and translates it to an ASCII
code of the character.
• OCR quality depends on software, quality of printed text, and type of
paper being scanned.
• Extensive editing may be required to remove stray characters or
misinterpreted text.
DIGITAL CAMERA
• Captures images in real time at the source.
• Benefits include:
• Instant review of image
• Re-capture the image if necessary
• High quality spatial and color resolution.
• Image file size depends on capture resolution (6 – 12 megapixel) and
color depth (16 – 24 bit color) can produce large file sizes.
• Images transferred to hard drive via memory card or USB direct
connection.
DIGITAL CAMERA
• Captures images in real time at the source.
• Benefits include:
• Instant review of image
• Re-capture the image if necessary
• High quality spatial and color resolution.
• Image file size depends on capture resolution (6 – 12 megapixel) and
color depth (16 – 24 bit color) can produce large file sizes.
• Images transferred to hard drive via memory card or USB direct
connection.
DIGITAL VIDEO (DV) CAMERA
• Video captured on built-in hard drive, mini-digital tape, or DVD.
Transferred to computer through FireWire interface.
Video editing software enhances digital sequences.
• Method used to capture image.
• Single chip reproduce RGB color.
• 3-chip have separate CCD for Red, Green, Blue.
• Lens quality.
• Zoom quality.
• Optical zoom vs. digital zoom.
• Image stabilization.
• Preprogrammed modes.
• Lighting and weather conditions.
SOUND CAPTURE
• Devices to transform analog waveforms to digital files.
• Microphones
• External vs. internal
• CD & Tape players
• Digital Recorders.
GRAPHICS TABLET
• Flat drawing surface for freehand image creation.
• User draws or traces image with a stylus then enhances the image
using software interface.
OUTPUT AND DISPLAY DEVICES
• Present processed data in a useful form.
• Devices include:
• Screen display
• Audio speakers
• Hard copy.
• Produce an image on a screen through a series of individual pixels.
• Display quality is determined by spatial and color resolution.
• Displays with 1024 X 768 spatial resolution have more addressable pixels than
640 X 480 resolution.
• 24-bit color graphics display has richer colors than 16-bit color.
CRT DISPLAY
• Raster scanning technology generates a display.
• Based on Cathode Ray Tube technology.
• Electronic signal scans
horizontal rows from
top to bottom of screen.
LCD & LED DISPLAY
• Use Thin Film Transistors (TFT)
• Assign a single transistor to each liquid cell to control color and light.
• LCD displays use fluorescent lamp to project through polarized liquid
crystals.
• LED displays use light emitting diodes for brighter backlighting and
more
vibrant colors.
• LED’s are becoming commonplace on
laptop and desktop computers.
• They use less power
• Display brighter, richer colors.
SPEAKER SYSTEMS
• Speakers or headsets are plugged into the soundboard where digital
data is converted to analog waveforms.
• Sound card circuitry performs four processes:
• Converts digital sound data into analog with DAC. (digital to analog converter)
• Records sound in digital form with analog ADC.
• Amplifies signal.
• Creates digital sounds using a synthesizer.
PRINTERS
• Two basic printing technologies:
• Impact, print head makes contact with the paper.
• Dot-matrix printer.
• Used for multi-part forms and low cost output requirements.
• Nonimpact, print head does not contact paper.
• Laser printer
• Ink-jet printer
• Photo printer.
NON-IMPACT PRINTERS
• Ink-jet printer.
• Line printer that delivers high quality color.
• Output quality determined by
• Printer resolution measured in dots/inch
• Paper quality.
• Photo printer.
• Delivers photo-lab-quality output directly from camera or card.
• Use inkjet cartridges or dye sublimation process to print image.
• Laser printer.
• Fuse text and image to paper one page at a time.
• High quality output resolutions of 600 to 2400 dpi.
• Deliver high quality color output using cyan, magenta, yellow,
and black toner.
NON-IMPACT PRINTERS
• Multifunction printer.
• Combines printer, scanning, fax,
and copier technology in one device.
View IT
Learn how laser
printers create
the output.
NETWORKS
• A collection of computers connected through a communication link to
share resources.
• Two main categories:
• WAN
• Covers wide geographic area using communication lines of an external service provider.
• LAN
• Computers and peripherals connected within an organization on privately owned
communication lines.
• A network of networks built on TCP/IP protocols.
• Transfer Control Protocol prepares data in packets to distribute on the
network.
• Internet Protocol assigns an numeric address to each packet of data.
NETWORKS
• Client/Server organization.
• Efficient means to distribute data from the server and rely on processing at the
client (local) computer.
• Commonly used on LANs and WWW.
• Ethernet.
• Protocol to control flow of data on LAN.
• WiFi & Bluetooth.
• Mobile computing network standards.
WWW
• WWW built on revolutionary http protocol.
• Hypertext transfer protocols included:
• Html code that programmed text and images on a web document.
• Hyperlinks to connect related “pages” on local and external servers.
• Uniform Resource Locator (URL) as the path address to create the hyperlink.
• URL includes the protocol, domain name of server, directory location, and the document
to view, often a .htm or .html page.
• Common Internet protocols:
• eMail — smtp
• File transfer — ftp
• Web — http.
http://jbpub.com/cis/new.htm
WRAP UP
• Computer systems
•
•
•
•
Supercomputer
Mainframe
Microcomputer
Mobile devices (iPad, iPhone, Ultrabook)
• System unit
• CPU
• Primary memory
• System board
• Interface ports
• USB
• FireWire
• Thunder Bolt
• Peripherals
•
•
•
Storage devices
Input devices
Output devices
• Networks
•
•
•
WAN
LAN
Internet
KEY TERM CHECK UP
Main Reference
Chapter
3:
“Computer
Systems,
Platforms,
and
Hardware ”, Savage T., & Vogel, K. (2014). An Introduction
to Digital Multimedia. (2 ed). Burlington: Jones and Barlett
Learning. ISBN: 144968839 (print), 9781449688394 (e-text).
Thank You
‫ر‬
‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Computer Science
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 4
Computer Software
Contents
1. Main categories of software
• Operating system
• Application
• Programming
2. Functions of the operating system
3. Types of programming languages
4. Software for multimedia development
Weekly Learning Outcomes
1. Identify the three main categories of software.
2. Analyze the different types of software used to develop
multimedia products.
3. Summarize the main types and uses of programming
languages.
Required Reading
Chapter 4 “Computer Software”, Savage T., & Vogel, K. (2014). An Introduction to Digital
Multimedia. (2 ed). Burlington: Jones and Barlett Learning. ISBN: 144968839 (print),
9781449688394 (e-text)
Recommended Reading
1. “The Programmer’s Price”
https://www.newyorker.com/magazine/2014/11/24/programmers-price
SOFTWARE
• A collection of computer programs that govern the operation of a
computer.
• Program: list of instructions that can be carried out by the computer.
• Three categories of software:
• Operating systems
• Programming languages
• Applications.
7
YOU DECIDE … Software
Label each as an operating system, programming language,
application.
1.
2.
3.
4.
5.
6.
7.
8.
Word
Photoshop
Java
OS X
Visual Basic
Flash
Windows 8
C+
9.
10.
11.
12.
13.
14.
15.
16.
Linux
Open Office
HTML
Javascript
Browser
Director
Unix
Assembly
8
OPERATING SYSTEM
• Collection of programs that:
• Provides a user interface
• Manages computer resources
• Executes application programs.
• User interface: a means to communicate with the programs and
hardware.
• Command line interface
• Graphical user interface (GUI)
• Natural user interface (NUI).
9
OPERATING SYSTEM
• Manages computer resources such as:
• Processor
• Memory
• Peripheral devices
• Networks.
10
MANAGE COMPUTER RESOURCES
• Manage the processor
• Controls how and when programs are executed.
• Control methods:
• Single user, single tasking
• Single user, multi-tasking
• If the processor is sufficiently powerful users are not aware
of sharing the resources.
11
MANAGE COMPUTER RESOURCES
• Manage memory
• Controls how much memory is accessed and used by
application programs.
• Virtual memory: operating system assigns a portion of
the hard disk to simulate RAM.
• Problem: access to files in virtual memory is slowed.
• Solution: install more RAM.
12
MANAGE COMPUTER RESOURCES
• Control peripherals
• Built-in programs control devices such as
monitors, printers, storage drives.
• Additional device drivers can be downloaded or
come with the installation CD.
• Plug and Play
• Operating system senses that a new device is
plugged into the system board and immediately
responds to “play” the device.
13
MANAGE COMPUTER RESOURCES
• Manage access and security of network
computers through:
• Built in protocols to connect to WANs (TCP/IP)
• Built in protocols to connect to LANs (Ethernet)
• Support for WiFi and Bluetooth connectivity
• Network firewall protection.
14
MANAGE COMPUTER RESOURCES
• Utility programs
• Tools to optimize operating system functions such as:
•
•
•
•
•
CD and DVD recording
Screen savers
Speech recognition for basic commands
Text editors
Multimedia utilities.
• Disk management utility
• Partition and format drives.
• Defragment and detect disk errors.
15
MANAGE COMPUTER RESOURCES
• File management.
• Operating systems govern storage and retrieval of files.
• Basic file management includes:
•
•
•
•
Copy
Delete
Rename
Move.
• File extensions identify a file as data or program for the
operating system.
16
FILE MANAGEMENT
• Directories are storage locations for groups of
files.
• Directory path is identified by the operating system.
• Directories (or folders) are created, moved, copied,
deleted using file management utility.
17
PROGRAMMING LANGUAGES
SYNTAX AND SEMANTICS TO WRITE COMPUTER
PROGRAMS.
18
PROGRAMMING LANGUAGES
• Low-Level Languages.
• Programs are written for a specific computer system.
• Machine code — binary code the processor directly executes.
• Assembly code — text abbreviations for binary commands.
• Requires a program (assembler) to convert the abbreviations to binary code.
19
PROGRAMMING LANGUAGES
• High-Level Languages.
• Syntax and semantics are not dependent on a specific computer system.
• More English-like commands.
• Easier to debug errors.
• Two methods to convert to machine code:
• Interpreter converts and executes one line of code at a time.
• Compiler converts entire program to an executable file.
20
Approaches to Programming
• Procedural approach:
• Follows a series of computational steps that focus on a
specific result.
• Divides complex tasks into subroutines, functions that can be reused
within a single program environment.
• Code modules cannot be ported to other applications without
significant modification which leads to inefficiency in programming
tasks.
• Non-procedural:
• Maximizes programmer productivity by recycling modules
from one program into other applications.
21
Two Non-procedural options
• Object-Oriented languages.
• Modular approach reduces time to recode similar object routines.
• Visual programming.
• Use graphical interface to expedite programming process.
• Enables Rapid Application Development.
22
APPLICATION SOFTWARE
SOFTWARE THAT PERFORMS A SPECIFIC TASK.
23
APPLICATION SOFTWARE
• Two main categories for multimedia development.
• Media-specific applications.
• Create and edit specific media content.
• Authoring applications.
• Tools to integrate media components and provide a user interface.
24
MEDIA-SPECIFIC APPLICATIONS
• Text media applications include:
• Word processors
• Text editors
• Portable document generators.
• Graphics media applications include:
• Paint programs
• Draw programs
• 3-D imaging applications.
25
MEDIA-SPECIFIC APPLICATIONS
• Sound media.
• Sound capture applications.
• Synthesized sound applications.
• Video applications combine:
• Source material
• Synchronize clips to sound track
• Add special effects
• Save as a digital video.
26
MEDIA-SPECIFIC APPLICATIONS
• Animation applications.
• Software to create and edit animated sequences.
• Objects are drawn or imported into the software where they are manipulated
in a series of frames.
• Media utilities.
• Add functionality to media-specific applications such as file compression and
file conversion.
27
AUTHORING SOFTWARE
• Programs designed to facilitate the creation
of multimedia products.
• Assemble media elements
• Synchronize content
• Design user interface
• Provide user interactivity.
• Authoring metaphors are:
PowerPoint uses a card metaphor.
• Card based
• Timeline
• Icon.
Flash uses a timeline metaphor.
Authorware uses a icon metaphor.
28
WRAP UP
• Three software categories.
• Functions of operating system.
• Disk and file management practices.
• Levels of programming languages.
• Application software for multimedia.
• Media-specific software.
• Authoring software.
29
KEY TERM CHECK UP
30
Main Reference
1. Chapter 4 “The Multimedia Revolution”, Savage T., &
Vogel, K. (2014). An Introduction to Digital Multimedia. (2
ed). Burlington: Jones and Barlett Learning. ISBN:
144968839 (print), 9781449688394 (e-text)
Thank You
‫ر‬
‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Information Technology
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 5
TEXT
Contents
1. Text tradition
2. Codes for computer text
3. Font technologies
4. Guidelines for use of text in multimedia
Weekly Learning Outcomes
1. Explain the key elements of traditional text, including typeface, font, style,
case, weight, kerning, tracking, leading, and justification.
2. Define the features and uses of multimedia text: editable vs. graphics text,
text and sound (speech recognition and speech synthesis), hypertext and
hypermedia, and multimedia text formats.
3. Summarize the basic guidelines for the use of text.
4. Articulate the major options for adding text to a multimedia application.
Required Reading
Chapter 5: “Text”, Savage T., & Vogel, K. (2014). An Introduction to Digital Multimedia. (2
ed). Burlington: Jones and Barlett Learning. ISBN: 144968839 (print), 9781449688394 (etext).
Recommended Reading
“As It Turns Out, a Picture Is Not Worth a Thousand Words”
https://www.wired.com/2014/03/turns-picture-worth-thousand-words/
1. Text tradition
POWERS OF TEXT
• Multimedia developers value text for:
• Universality
• Clarity
• Efficiency
• Powers of abstraction, engagement, and suggestion.
• Developers can explore new uses for text in a media-rich environment.
• Text properties are grounded in the print tradition.
• Typeface is a family of characters sharing a common design.
• Arial
• Chicago
• New York
• Palatino
TEXT TRADITION
Typefaces are commonly categorized as:
• Serif
• Sans serif
• Script
• Symbols.
• Style: appearance of characters such as:
• Bold
• Italic
• Underline.
• Point size: measure of type size.
• Case
• Upper and lower case.
Aa
Point is approximately 1/72 of an
inch.
Pica is 12 points
6 picas = 1 inch.
TEXT TRADITION
• Font
• Complete set of characters of a particular typeface, style, and size.
• Monospaced fonts: same width assigned to each character.
• Proportional fonts: adjust width based on shape.
• Weight
• Line thickness of the typeface.
• Arial Black has heavier weight.
• Kerning
• Adjusting spacing between specific letters.
• Tracking
• Adjusting spacing between all characters.
TEXT TRADITION
• Condensed/extended text
• Narrow width of text / widen width of text.
• Leading
• Spacing between lines.
• Alignment & Justification
• Alignment positions text relative to document’s margins.
• Justification adjusts line length to produce straight edges on left and right
margins.
2. Codes for computer text
COMPUTER TEST CODES
• Coding schemes assign a group of binary numbers to represent a
digital character.
• ASCII
• 7-bit code = 128 characters.
• Extended ASCII or ASCII-8
= 256 characters.
• All computers understand ASCII.
COMPUTER TEST CODES
• RTF (Rich Text Format)
• Developed by Microsoft for cross platform text files.
• Reproduces the formatting of original file.
• Unicode
• New standard 16 bit code that provides for more than 65,000 characters.
• Goal is to include multilingual text
in a digital coding standard.
FONT TECHNOLOGIES
• Two techniques for displaying text on computer:
• Bitmapped fonts : Pixels that make the letter are described by a binary
code, or a “mapping” of the character.
• Every character is stored as a bitmapped letter, number, or symbol.
• Require large memory and storage capacity.
• Outline fonts.
• Outline Font: Store a description of the character to be displayed.
• Description is a series of commands to create the letter on the computer
display.
• Outline font technology:
• Adobe Postscript
• TrueType.
BITMAPPED FONTS
OUTLINE FONTS
• Advantages
• Advantages
• Precise control over letter
appearance.
• Letters can be edited at pixel level.
• Disadvantages
• Letters can’t be easily scaled.
• Requires separate bitmaps for each
typeface, style, and point size to be
used.
• Requires large storage capacities.
• Limits flexibility in use of text fonts
to those stored on the computer.
• Fonts are easily scaled.
• Requires smaller storage capacity.
• Disadvantages
• Commands can’t be edited to
create unique characters.
• Font families are controlled
through license of Postscript and
TrueType fonts.
JAGGIES and TEXT
• Text is displayed on a monitor as a pattern of pixels.
• Pixels are generally very small squares.
• Squares can display straight lines with smooth edges.
• Squares that display curved or diagonal lines produce a stair-stepped effect
called JAGGIES.
• Jaggies produce an alias of the true character.
• Anti-aliasing creates a smooth edge by blending the color of the text
with the color of the background.
INSTALLED FONT
• ASCII and Unicode are standard.
• Fonts are not standardized across computer platforms.
• If the font is not available on the computer, it will substitute one that is.
• The result may not be acceptable.
• Solution
• Use only widely available fonts.
• Package the unique font with the application.
3. Guidelines for use of text in multimedia
MULTIMEDIA TEXT
• Two main forms:
• Editable: text produced by word processors or text editors.
• Easy to alter content.
• Can search and spell check.
• Graphics: image of text that can be manipulated to produce a wide range of
artistic effects.
• Make original word picture.
• Solves problem of installed fonts.
MULTIMEDIA SOUND
• Speech recognition: software analyzes human speech and converts
words to editable text.
• Requires specialized “intelligent” software.
• Accuracy may depend on training and speaker’s voice.
• Speech synthesis: software analyzes text and reproduces it as spoken
words.
TEXT & INTERACTIVITY
• Hypertext is linked text.
• User interacts with links to trace relationships of words and ideas created by
the author.
• Structure consists of:
• Nodes
• Link anchor
• Link markers
• Hypermedia is an information structure based on linked media.
Hyperlink
text can take
you places.
TEXT FOR THE WWW
• HTML: hypertext markup language.
• Contains “tags” used to specify the structure of the document and format the
text and media.
• Browser interprets the “tags” and displays the “page” on a client computer.
• HTML limitations:
• Limited set of tags to create a page.
• Difficult to precisely define a page appearance.
• Some browsers and client computers may present the html page differently from other
browsers.
CSS & HTML
• Cascading Style Sheets (CSS).
• An addition to HTML
• Separates content of page from formatting commands
• Easier to edit and maintain consistent appearance of a site.
• eXtensible HTML (XHTML)
• A blending of HTML and XML
• XML supports more powerful data manipulation.
• XHTML improves page display on mobile devices.
PORTABLE DOCUMENT FORMAT
• PDF files maintain original formatting of documents across computer
platforms.
• Platform and application independent.
• Support multiple media and user interaction.
• Require a reader program to view the file and an application to convert a
document to pdf format.
• Adobe Acrobat Reader is a free download.
• PDFCreator is a free open source converter.
ADDING TEXT TO MULTIMEDIA APPLICATION
Several methods to incorporate text in an authoring application.
• Direct entry in a text box or text field.
• Copy and paste from existing text source.
• File import for large text files.
• Scan text with OCR application for text that exists only in print media.
• Optical Character Recognition accuracy will vary based on fonts and quality of source
material.
4. Guidelines for use of text in multimedia
GUIDELINES
• Be selective.
• Be brief.
• Make text readable.
• Be consistent.
• Be careful
• Be respectful.
• Combine text with other media.
• Make text interactive.
WRAP UP
• Traditional text features.
• Computer text codes.
• Font technologies.
• Multimedia text.
• Adding text to multimedia applications.
• Guidelines for using text.
KEY TERM CHECK UP
Alignment
Anti-aliasing
ASCII
Bitmapped fonts
Browser
Case
Condensed text
Editable text
Extended text
Font
Font te chnologies
Graphics text
HTML
Hypermedia
Hyperte xt
Jaggies
Justification
Kerning
Leading
Link anchor
Link markers
Monospaced font
Nodes
OCR
Outline fonts
PDF
Point
Proportional font
RTF
Sans ser if
Serif
Speech rec ognition
Speech synthes is
Style
Tracking
Typeface
Unicode
Weight
XHTML
XML
Main Reference
Chapter 5: “Text and Multimedia Application”, Savage T., &
Vogel, K. (2014). An Introduction to Digital Multimedia. (2 ed).
Burlington: Jones and Barlett Learning. ISBN: 144968839
(print), 9781449688394 (e-text).
Thank You
‫ر‬
‫الجامعة السعودية االلكتونية‬
‫‪26/12/2021‬‬
College of Computing and Informatics
Bachelor of Science in Computer Science
IT441
Multimedia System Development
IT441
Multimedia System Development
Week 6
Graphics
Contents
1. Key elements of traditional graphics.
2. Features and uses of computer graphics.
•
Bitmapped images.
•
Vector-drawn images.
•
3-D graphics.
3. Guidelines for using graphics in multimedia.
Weekly Learning Outcomes
1. Identify key elements of traditional print graphics such as
contones, line art, linescreen, and CMYK color.
2. Explain essentials of 3- D graphics such as modeling, surface
definition, scene composition, and rendering.
3. Articulate basic guidelines for the use of graphics in
multimedia applications.
Required Reading
Chapter 6 “Graphics”, Savage T., & Vogel, K. (2014). An Introduction to Digital Multimedia.
(2 ed). Burlington: Jones and Barlett Learning. ISBN: 144968839 (print), 9781449688394
(e-text)
Recommended Reading
1. “9 of the World’s Leading Designers Talk About What Matters Now”
https://www.wired.com/2015/01/what-matters-to-the-worlds-most-importantdesigners/
2. “Why We Need Free Digital Hardware Designs”
https://www.wired.com/2015/03/need-free-digital-hardware-designs/
MULTIMEDIA & GRAPHICS
• Graphics covers wide range of pictorial representations.
• Computers are able to carry out many tasks of a traditional artist or
designer.
• New uses for computer graphics include:
• Buttons
• Charts
• Diagrams
• Animated images.
7
MULTIMEDIA GRAPHICS
• Challenges of computer images include:
• Large file size
• Slow downloads and processing
• Possible inferior quality from original
• File format compatibility
• Images display differently on various monitors and printers.
8
TRADITIONAL GRAPHICS
• Contone image
• Composed of continuously varying shades of color.
• Line art
• Combinations of lines to create images.
• Uses only two colors.
9
TRADITIONAL GRAPHICS
• Black and white image reproduction.
• Images are made with a series of ink dots.
• Linescreen, or lines per inch, designates the size of the dots and quality of
resulting image.
• 150 lpi better quality than 85 lpi.
• Halftones form image by
clustering the ink dots.
• Tight cluster of black and white
dots create dark gray.
• Loose clusters create
lighter tones of gray.
10
TRADITIONAL GRAPHICS
• Color image reproduction.
• Use a series of four-color dots of transparent inks.
• CYMK
• Cyan, magenta, yellow, and a key
color usually black.
• Small dots of color combinations
can reproduce many different colors.
11
COLOR REPRODUCTION
• Color images on printed surface are formed using subtractive process.
• Light is reflected from the printed surface.
• Pigments that form image absorb some of the colors.
• Remaining colors reach the eye to produce image.
• Color images on computer monitor use additive process.
• Varying amounts of Red, Green, and Blue light are added together to create the
color.
• Graphic artists convert from RGB(additive) color models to CMYK
model if image is printed.
12
2-D COMPUTER GRAPHICS
BITMAPPED IMAGES &
VECTOR DRAWN GRAPHICS
13
BITMAPPED GRAPHICS
• Bitmapped graphics
• Created as a pattern of discrete elements.
• Each element is a pixel or “picture element.”
• Pixels
• Small squares.
• Assigned a binary code to define color.
• More bits = more color possibilities
14
BITMAPPED IMAGES
• Categories of bitmapped images are:
• Line art
• Produced using two colors.
• Grayscale
• Produced using shades of gray.
• Color
• Produced with patterns of colored pixels.
15
BITMAPPED IMAGES
• Line art
• Two colors, usually black and white.
Line art is
1-bit color
• Advantages
• Clear, crisp image.
• Small file size.
• Uses include:
• Charts
• Illustrations
• Diagrams.
Line art flow chart
diagram
16
BITMAPPED IMAGES
• Grayscale
• Generally 8-bit images of 256 shades of gray
• For images that require more detail than line art.
• Advantages
• Excellent representation of black and white photos
• Smaller files size than full color
• Lower printing costs than color.
17
BITMAPPED IMAGES
• Color
• Consists of a pattern of colored pixels
• Bit depth: the number of bits used to encode each pixel determines the
amount of color possibilities.
• Photo-realistic color requires 24-bit color.
• Two methods to create color on a computer:
• Identify a table of possible colors for the computer (Color Lookup Table)
• Specify varying amounts of Red, Green, Blue.
18
MAKING COMPUTER COLOR
• 8-bit color presents a specific range of colors in a table.
• PCs and Macs use different tables.
• Web-safe table provides colors that display the same on all platforms.
• 24-bit color combines 8-bit values of red, green, or blue to create the
result.
• 16.7 million color possibilities.
• 48-bit color has 16-bit values
• 281 trillion color possibilities.
19
BITMAPPED IMAGE QUALITY
• Image quality depends on spatial and color resolution.
• Spatial resolution = density of pixels per inch.
• Color resolution = number of colors each pixel can display.
• Spatial resolution measurements.
• Monitor output is measured in ppi (pixels per inch).
• Print output is measured as dpi (dots per inch).
20
SPATIAL RESOLUTION
• Higher spatial resolution
• Captures more detail.
• Pixels are smaller and closely packed.
• Produces sharper, more accurate images.
• Lower spatial resolution
• Captures less detail.
• Pixels are larger.
• Images appear fuzzy.
• High spatial resolutions yield large file sizes but
better image quality.
21
DEVICE-DEPENDENCE
• Dimensions of an image depend on the resolution of the
output device.
• Monitors have low spatial resolution:
72 ppi (Mac) or 96 ppi (PC).
• Printers have higher spatial resolutions:
300 dpi to 2400 dpi.
• Bitmapped images are device-dependent.
• 300 ppi image prints the original size on 300 dpi printer.
• Same image is greatly enlarged on a 72 ppi monitor.
22
COLOR RESOLUTION
• Bit-depth determines color resolution.
• Making the bit-depth choice:
• Simple color images do not require many colors. Low bitdepth yields small file size.
• Complex color images require millions of colors. High bitdepth yields better quality but larger files.
• Low color resolution may cause quantization and color
banding.
• Quantization leads to breaks
in shades of continuous tone images.
23
RESAMPLING BITMAPPED IMAGE
• Process of increasing or decreasing the number of
samples described in a file.
• Often need to control spatial resolution of bitmapped images.
• 72 ppi for web display.
• 300 ppi for laser output.
• Upsampling: adding samples to the file.
• Downsampling: reducing the samples in the image.
24
RESAMPLING BITMAPPED IMAGE
• Upsampling used to enlarge the physical dimensions of
an image on a given device.
• Software creates additional pixels for the image.
• Algorithms interpolate the pixel and color to add.
• Can significantly degrade the original image.
25
RESAMPLING BITMAPPED IMAGE
• Downsampling: reducing the pixels in the file can
produce smaller images that maintain good quality.
• Best Practice:
• Capture at highest possible spatial resolutions when possible
and downsample as needed for various uses of the image.
26
RESIZE without RESAMPLING
• A bitmapped image can be resized without resampling.
• Enlarging a printout may produce acceptable results.
• Caution: excessive enlargement will distort the image with blocky, mottled surface
appearance.
• Reducing the image size without resampling can produce high quality
printouts.
• Pixels are packed more closely together.
27
RESIZE without RESAMPLING
• Excessive enlarging
without resampling
can lead to distorted
images.
28
RESIZE without RESAMPLING
• Resizing without resampling has no effect on monitor
display of image.
Note: pixel dimensions of image remain the same in both dialog boxes.
29
COLOR RESOLUTION
• Indexing
• A specific palette of colors is identified to optimize the
appearance of lower color resolution image.
• Two methods to create the index of colors:
• Adaptive
• Perceptual.
• Dithering
• Combining pixels of different colors to produce another color not
available in the indexed palette.
• Improves image quality without increasing bit depth.
30
BITMAPPED IMAGE SOURCES
• Paint programs
• Specialized software for creating bitmapped images.
• Photoshop
• Paint.
• Digital cameras
• Number of pixels sampled by the camera is the camera’s spatial resolution.
• Measured in megapixels.
31
BITMAPPED IMAGE SOURCES
• Scanner
• Capture existing or original art image
• Capture 3-D objects.
• Clip art
• Royality free
• Licensed usage.
• Screen grab
• Save image on monitor to a bitmapped file
• Spatial resolution is generally low.
32
BITMAPPED FILE FORMATS
• Compression of bitmapped graphics are:
• Lossy
• Lossless.
• Common graphic file formats are:
• PICT
• BMP
• TIFF
• JPEG
• GIF
• PNG.
What form of
compression do
each of these
formats use?
33
VECTOR-DRAWN GRAPHICS
• Vector: a line with length, curvature, and direction.
• Vector graphics: images created from mathematically defined shapes.
• Draw programs: software used to create vector graphics.
• Main advantages:
• Images can be enlarged without distortion
• Small file size.
34
VECTOR-DRAWN GRAPHICS
• Draw programs use tools that resemble those of a draftsman:
• Fixed shapes
• Bezier curves
• Pen.
• Objects are layered on each other and grouped to form complex
images.
• Grouping joins individual shapes.
• Ungrouping restores image
to separate shapes.
35
DEVICE INDEPENDENCE
• Vector graphics can be used with different devices without altering
the image dimension.
• Printers and monitors preserve the original dimension of the image.
36
VECTOR to BITMAPPED
& Back Again
• Autotracing: software analyzes a
bitmapped image for shapes and converts
the image to a vector graphic.
• Rasterizing: samples the vector image and
saves it in bitmapped form.
• Vector graphics displayed on a screen can be
screen grabbed and saved as a bitmapped
graphic.
Bitmapped
Autotraced
37
VECTOR GRAPHIC FILE FORMATS
• Files are saved in native format or general purpose formats.
• Native format: dependent on the application.
• General purpose: can be used in many applications.
• Vector-only:
EPS—Encapsulated Postscript
PDF— Portable Document Format.
• Metafiles:
SVG—Scalable Vector Format.
38
ADVANTAGES
BITMAPPED IMAGES
• Represent complex
contones.
• Full-featured photo
editing.
• Wide range of artistic
effects.
• Precise editing.
VECTOR IMAGES
• Smooth scaling and
reshaping.
• Ease of editing objects in
layers.
• Low file size.
• Device-independent.
39
DISADVANTAGES
BITMAPPED IMAGES
• Large file sizes.
• Loss of precise shapes
when scaled or rotated.
• Device-dependent.
VECTOR IMAGES
• Inaccurate, incomplete
representation of complex
contone images.
• No photo-editing
capability.
• Limited artistic control.
40
3-D COMPUTER GRAPHICS
PRODUCE THE ILLUSION OF DEPTH
ON A FLAT SURFACE.
41
3-D GRAPHICS
• Computer becomes a virtual partner in the creative process.
• Four interconnected steps in creating 3-D images:
• Modeling
• Surface definition
• Scene composition
• Rendering.
42
STEP 1: MODELING
• Process of specifying the shape of the 3-D object.
• Two major approaches to modeling:
• Combine cubes, cones, cylinders and other 3-D shapes
supplied with the graphics program – modeling with
primitives.
• Use a modeler to create shapes directly.
43
3-D MODELING
• Modeling with primitives uses basic shapes to create complex 3-D
images.
• Parametric primitives
• Objects that can be changed by specifying parameters such as radius.
• Primitives can be scaled, rotated, moved, combined.
• Constructive Solid Geometry (CSG)
• Primitives are joined, subtracted from, or intersected with using Boolean operators.
44
View IT
3-D MODELING
Tutorial on
modeling a
hand.
• Four modeling techniques:
• Polygon modeling
• Spline modeling
• Metaball modeling
• Formula modeling.
• Modelers have ability to:
• Extrude: extend a 2-D shape through space to create a 3-D object.
• Lathe: rotate a 2-D line on an axis.
45
POLYGON MODELING
• Object is defined as pattern of straight-edged
polygons.
• Similar to bitmapped graphics in that the object is defined by
fixed number of elements.
• Fixed number of polygons for 3-D.
• Fixed number of pixels for 2-D.
• Advantages:
• High-quality, realistic surfaces,
and precise editing control.
• Disadvantages:
• Large file sizes and scaling distortions.
View IT
Polygon
modeling
demonstration
on YouTube.
Design your own 3D model with Lego Digital Designer.
46
SPLINE MODELING
• Uses curves to create objects. Similar to 2-D vector
graphics.
• NURB approach defines an image using mathematical
formulas that can be adjusted to vary size and shape.
• Advantages:
• Smaller file sizes,more flexible objects,
NURBs are easily scaled.
• Disadvantage:
• Less editing control.
View IT
Spline modeling
of car on
YouTube.
47
METABALL MODELING
• Creates objects as combinations of elements called
blobs.
• Blobs have various shapes and are either positive or
negative.
View IT
Demonstration of
modeling a head
in Blender on
YouTube.
• Positive blobs add to the object.
• Negative blobs subtract from the object.
• Metaball technique is good
for objects with soft edges.
The blobs are smoothed like
lumps of clay.
48
FORMULA MODELING
• Creates objects by specifying mathematical formulas
that are drawn by the computer.
• Requires knowledge of programming and advanced
mathematics.
49
STEP 2: SURFACE DEFINITION
• Surface definition: where textures are applied to
the model’s surface.
• Menu choices of surfaces include wood, glass, metal,
skin.
• Can vary the appearance of surfaces with color, opacity,
reflectivity.
• Custom surfaces include:
• Image maps
• Bumb maps.
50
STEP 3: SCENE COMPOSITION
• Objects are arranged, backgrounds introduced, environmental effects
added, and lighting established.
• Lighting choices in a scene include:
• Omni lights
• Directional lights
• Spot lights
• Volumetric light.
• Adjust lighting with brightness, color, and attenuation.
51
STEP 4: RENDERING
• Computer creates the scenes specified by the artist.
• Two main approaches:
• Pre-rendering
• Used primarily for still graphics, animation, and video with limited interactivity.
• Real-time rendering
• Used for highly interactive 3-D applications such as video games.
52
RENDERING (cont.)
• Forms of rendering to create test scenes in 3-D graphics:
• Wire frame rendering
• A series of lines used to define the shape of an object without defining its surface.
• Useful to test the basic geometry and placement of an object.
53
RENDERING (cont.)
• Surface rendering applies lighting and shaders
to the object.
• Flat shaders, has imperfections but a fast render
process.
• Smooth shaders, better quality surface.
• Ray tracing, traces each ray of light as it interacts
with objects on a scene.
• Radiosity, recreates the changes that result from
interaction of different wavelengths of light.
54
FINAL RENDER
• Final rendering translates 3-D information to a 2-D image.
• Rendering engines apply effects to the finished product such as
shadows, reflections, bumps, transparencies and lighting
considerations.
• Successful rendering requires processing power, time, and artistic
talent.
55
CREATING WORLDS
• 3-D graphics are powerful tools to create reproductions of the world
around us.
• Fantasy worlds come alive with creative artists and software
applications such as Maya, Blender, Zbrush, 3-D StudioMax.
• Check it out at Second Life.
• Education in a virtual world.
56
GUIDELINES FOR USING
GRAPHICS IN MULTIMEDIA
1. Identify purpose of the 5. Preserve image quality.
graphic.
6. Economize.
2. Choose best format for
7. Organize and store
each image.
graphics files for later
3. Match graphic design
use.
to purpose.
4. Locate graphics.
57
WRAP UP
• Traditional graphics characteristics.
• Contones and Line Art.
• Image Reproduction techniques.
• 2-D computer graphics.
• Bitmapped and Vector graphics.
• Features & sources of bitmapped graphics.
• Features of vector graphics.
• 3-D computer graphics.
• Steps to create 3-D images.
58
KEY TERM CHECK UP:
Adaptive indexing
Additive color
Autotrac ing
Bit depth
Bitmap
Bitmapping
BMP
Clip art
CMYK
Color banding
Color indexing
Color palette
Color resolution
Contone
Device-dependent
Device-independent
Dithering
Downsampling
Dpi
Draw program
EPS
Extrusion
Formula modeling
GIF
Graysca le
Halftone
Handles
Inter lacing
JPEG
Lathing
Layers
Line art
Lossless
Lossy
Megapixel
Metaball modeling
Modeler
Modeling
NURB
Paint program
Palette flashing
PDF
Perceptua l indexing
PICT
Pixel
PNG
Polygon modeling
Ppi
Primitives
Quant ization
Raster ize
Render ing
Resampling
Scene co mposition
Screen gr ab
Shader
Spatial resolution
Spline modeling
Subtractive color
Surface def inition
SVG
TIFF
Upsampling
Vector
Vector gr aphics
Web-safe co lor palette
59
Main Reference
1. Chapter 6 “The Multimedia Revolution”, Savage T., &
Vogel, K. (2014). An Introduction to Digital Multimedia. (2
ed). Burlington: Jones and Barlett Learning. ISBN:
144968839 (print), 9781449688394 (e-text)
Thank You
CHAPTER ONE
MULTIMEDIA
REVOLUTION
Chapter Highlights
• Nature of a revolution.
• Definition of modern multimedia.
– Forms of multimedia.
• Origins of multimedia.
• Visionaries of multimedia.
• Potential of digital media.
MULTIMEDIA DEFINED
Contemporary Multimedia is the development,
integration, and delivery of any combination of
text, graphics, animation, sound or video
through a digital processing device.
FORMS OF MULTIMEDIA
• Non-interactive
– User is a observer of information.
• Interactive
– User is a participant in the flow of information.
FORMS OF MULTIMEDIA
• Non-Interactive
– User has no control over the flow of information.
– Developer establishes the sequence of media
elements and how they are presented.
– Examples include:
• Information kiosks
• Digital animations.
INTERACTIVE MULTIMEDIA
• Basic interactivity
– Includes menu and button options to access
content.
• Adaptive or Intellimedia
– Adapt the information flow to the needs or
interests of the users.
• Immersive
– Draws users into an alternate world.
MULTIMEDIA VISIONARIES
FROM ANALOG TO DIGITAL:
VISIONS OF THE FUTURE.
VANNEVAR BUSH (1890 – 1974)
Memex I
1945
A hypothetical machine to make the work
of scientists more effective and efficient in
grasping the “growing mountain of
research.” (As We May Think, 1945)
MEMEX I — FEATURES
• Massive storage capacity.
• Multimedia input devices such as “vocoder”
and “cyclops camera.”
• Automatic mathematical calculations and
logical reasoning.
• New method to store and access information
by associations.
MEMEX II
1959
• Extended the original proposals of Memex I by
considering new technical developments such
as:
– Magnetic tape
– Transistor
– Digital computer.
MEMEX II — FEATURES
• Professionally maintained associational
databases delivered by tape or facsimile.
• Trails would be color-coded to reflect age and
reinforced by repetitive use.
• Combined with a digital computer, Bush
believed the Memex II could learn from
experience and even demonstrate a form of
judgment.
ALAN TURING (1912-1954)
• Proposed an abstract machine known as the
“Turing Machine.”
– The “machine” was a means of defining an
“effective procedure.”
– The imaginary device had three components:
• An infinitely long tape consisting of single row of
squares
• A read/write head that moved along the tape one
square at a time
• A set of instructions.
TURING MACHINES
• Single Purpose “Turing Machine.”
– Can carry out a specific set of instructions or
“effective procedure.”
• “Universal Turing Machine” (UTM).
– Can accept a description of a single purpose
machine and imitate it’s behavior.
– Implication of the UTM:
If we can think of a way to do something, the
computer can do it.
DOUGLAS ENGELBART
• Proposed practical applications of computers
beyond the normal mathematical and sorting
functions.
• Developed innovations for human-computer
interactivity in the NLS (oNLineSystem). These
included:
– Mouse
– Multiple screen areas for text editing
– Email.
THEODORE NELSON
• Coined terms hypertext and hypermedia.
– Hypertext: interactive text linked to other textual
information.
– Hypermedia: extends interactive linking to other
media
• Initiated Xanadu Project:
– A dynamic, expanding, hypertext library available
to everyone.
– Supported collaborative editing, tracking changes,
crediting, and rewarding contributors.
ALAN KAY
• Proposed a computer design that supported
the ways people perceive, learn, and create.
• Dynabook: designed as a personal computer.
– Tied to the mind and interests of the user.
– A “modeless” multimedia computer.
• Users could move between graphics, sound, text,
animation seamlessly.
• Introduced Graphical User Interface (GUI) as
an intuitive interface for the Dynabook.
STEVE JOBS (1955-2011)
• Founded Apple in 1976 with Steve Wozniak.
• Macintosh computer introduced in 1984.
– Graphical desktop and Icons provide user
interface.
– First mass produced computer with built in sound
support.
– Multimedia computing became the standard for
modern computers.
TIM BERNERS-LEE
• Developed a decentralized information system
of “nodes” linked together for easy access
across a network.
– Nodes could be any form of media.
– Anyone could add nodes.
– No centralized control over servers, documents or
links.
WORLD WIDE WEB
• Basic components of WWW:
– Server computer
– Client computer
– Browser software
– HTML scripting language.
WWW & MULTIMEDIA COMPUTING
• Solved cross-platform compatibility problem.
• Supported distribution of media beyond the
capacity of CD-ROM storage.
• Allowed instant distribution and inexpensive
media creation.
MULTIMEDIA VISIONARIES
• First Generation
– Alan Turing
– Vannevar Bush
• Second Generation
–
–
–
–
–
Douglas Engelbart
Theodore Nelson
Alan Kay
Steve Jobs
Tim Berners-Lee
• Next Generation
– Current innovators of multimedia
THE REVOLUTION CONTINUES
• Factors influencing the revolution:
– Technical breakthroughs in hardware and software.
– Integration of computers with other devices.
– Digital merger of disparate technologies and
industries.
– Further development of wireless communications &
mobile devices.
– Expansion of creative opportunity.
WRAP UP
• Definition of contemporary multimedia.
• Expressions of multimedia.
• Visionaries who contributed to development
of digital multimedia.
• Potential of digital media.
• The analog-to-digital revolution.
KEY TERM CHECK UP
CHAPTER TWO
DIGITAL DATA
CHAPTER HIGHLIGHTS
• Elements of digital media.
• Digital codes.
• Digital files.
• Digitization process.
• Compression for digital media.
• Advantages of digital media.
• Challenges of digital media.
26
CODING DIGITAL INFORMATION
• Symbols represent something else.
– Organized and understood by a conventional
standard.
• Data are the givens of experience.
– Measurements, facts, observations.
• Information is data made useful, interpreted,
and applied to produce understanding.
27
YOU DECIDE: data or information?
People who are 30 years old, pay $30
to run 30 miles in 30 degree weather for
a charity benefit.
Age = 30 yrs.
Temperature = 30 degrees
Distance = 30 mi.
Cost = $30
28
ANALOG vs. DIGITAL DATA
• Analog data varies continuously.
• Digital data consists of separate, discrete
units.
Wind mill motion.
Hour glass to tell time.
Numbers
1, 2, 3, 4
YOU DECIDE: Analog or Digital Data?
29
DIGITAL DATA
• Digit = number.
• Binary digit (bit) = 0 or 1.
• Bits are the symbols to encode digital data.
• Digital encoding assigns bits to data items.
Letter A
Number 5
0100 0001
0011 0101
More bits in the code, means more distinct items to encode.
30
BUILDING DIGITAL CODES
• Number of distinct bit combinations that can be
n.
produced is given by the formula 2
– n = number of bits used in the code.
• Adding 1 to the power doubles the number of
distinct data items that can be encoded.
21
22
23
24
2 items
4 items
8 items
16 items
25
26
27
28
Complete the table to identify the number of distinct items
5,
6,
7,
8.
represented by 2 2 2 and 2
31
COMMON CODES
• ASCII, a 7 bit code.
– 128 letters, numbers, and symbols in English language.
• ASCII-8, an 8 bit code.
– 256 letters, numbers, and symbols in English language.
• Unicode, a 16 bit code.
– Over 65,000 different characters.
• 24-bit color.
– Displays the full range a human eye can perceive.
• 16-bit sound.
– Plays the full decibel range the human ear can perceive.
32
DIGITAL FILES
• A container for binary codes.
• File formats define how instructions and data
are encoded in the file.
– Sample formats that define data differently:
• Word file format
• Acrobat file format
• Media player file format.
33
ALL ABOUT FILES
• File size
– Measured in units of bytes.
• Kilo Bytes, Mega Bytes, Giga Bytes.
• File extensions
– Series of letters to designate the file format.
• .fla, .exe, .rtf, .jpg
• File compatibility
– Ability to use the file in a different platform of
hardware and software.
34
FILE TYPES
• Program files
– Contain executable instructions.
• Data files
– Can hold text, images, sounds, video, animation.
35
DATA FILE COMPATIBILITY
• Cross-platform compatible files.
– Open and use on any computer hardware and
software configuration.
• Files that are native or specialized to the
application that created the data file.
– Require source application to open the file.
36
FILE MAINTENANCE
• Data loss and destruction impacts multimedia
project completion.
• Effective file maintenance involves:
– Identification
– Categorization
– Preservation.
37
DIGITIZATION
ANALOG TO DIGITAL CONVERSION.
38
SAMPLING ANALOG DATA
Sampling analyzes a small portion of the analog
source and converts it to digital code.
39
SAMPLE QUALITY
• Factors that influence sample quality
– Sample Resolution.
• Number of bits used to represent digital sample.
• Quantization is process of rounding off the value of a
sample to the nearest available digital code.
– Sample Rate.
• Number of samples taken in a given unit of time
(sounds) or space (images).
• Spatial resolution describes sample rate in image files.
40
YOU DECIDE … sample resolution
Which image and sound sample will have better quality?
Image
Sound
8 bits / sample
8 bits / sample
24 bits / sample
16 bits / sample
Which image uses fewer bits to describe the color sample?
41
YOU DECIDE … sample rate
Which image and sound sample will have better quality? Why?
Image
Sound
72 pixels / inch
11 kHz
300 pixels / inch
44 kHz
Which image has higher spatial resolution?
50ppi
300ppi
42
DIGITAL ENCODING
• Description-based encoding
– A detailed representation of the discrete elements
that comprise the media.
• Command-based encoding
– A set of instructions the computer follows to
produce the digital media.
43
MEDIA ENCODING COMPARED
Description
Command
Advantages
Represent natural scenes and
File sizes are small.
sounds.
Supports detailed editing.
Large file sizes.
Lose quality if enlarged.
Scaled without distortion.
Limitations
Not appropriate for detailed photographs
and natural sounds.
Requires knowledge of music and vector
image creation.
44
FILE COMPRESSION
• Process of re-encoding digital data to reduce
file size.
• Codec: a program to compress a file into a
smaller size and decompress it into a usable
form.
45
MAJOR TYPES OF COMPRESSION
• Lossy
– Number of bits is reduced and some data is lost.
– Lossy strategies include MP3 and JPEG
compression.
• Lossless
– Efficient encoding reduces file size without loss of
original data.
– Lossless strategies include RLE and GIF
compression.
46
YOU DECIDE… Lossy or Lossless
Choose a compression strategy best suited for:
1. Photograph of sailboat on ocean.
2. Journal article explaining nanotechnology.
3. 1812 Overture by New York Philharmonic
Orchestra.
4. Database of student names and addresses.
5. Video of hot air balloon flying over a cornfield.
47
ERROR DETECTION &
CORRECTION
• Digital bits may be lost during transmission or
damaged on storage media.
– CDs get scratched.
– Communication lines have interference.
• Strategies to preserve data vary.
– Parity bits help detect an error during
transmission.
– CDs include redundant data to replace data when
an error occurs.
48
DIGITAL INFORMATION —
ADVANTAGES
• Reproduction without generation decay.
• Editing and re-editing much easier than with
analog media.
• Integration of media using cut, copy, paste
more efficient.
• Distribution over Internet – nearly everyone can
be reached by anyone else.
49
DIGITAL INFORMATION —
CHALLENGES
• File sizes are large.
• Digital media is processor intensive.
• Absence of media standards renders data files
incompatible.
• Some media requires high bandwidth to
distribute on networks.
• Concern for longevity and future accessibility
of digital data.
50
WRAP UP
• Analog vs. Digital data.
•
•
•
•
•
•
•
•
Symbols and binary code.
Data vs. Information.
Files as containers.
Digitization process.
Description- vs. Command-based media.
Compression strategies.
Error detection & correction.
Advantages & Challenges of digital data.
51
KEY TERM CHECK UP
Analog data
ASCII
ASCII-8
Bandwidth
Bit
Bitmapped image
Byte
Codec
Command-based
Compression
Convention
Data
Data file
Description-based
Digital data
Digital encoding
Digitization
Effective code
Efficient code
Extended ASCII
File compatibility
File conversion
File extension
File format
Generation decay
Gigabyte
Incompatible
Information
Kilobyte
Lossless compression
Lossy compression
Megabyte
MP3
Native file format
Parity bit
Platform
Program file
Quantization
RLE
Sample rate
Sample resolution
Sampled sound
Sampling
Spatial resolution
Symbol
Terabyte
Unicode
CHAPTER THREE
COMPUTER
HARDWARE
CHAPTER HIGHLIGHTS
• Components of a Computer System
• Types of Computer Systems
• Computer Platforms
• Hardware Basics
– System Unit
– Peripheral Devices
•
Network Fundamentals
– WAN and LAN
– Internet
54
COMPUTER SYSTEMS
• An integrated set of hardware and software
designed to process data and produce a
meaningful result.
• Basic functions:
– Input
– Processing
– Storage
– Output
– Transmission.
55
TYPES OF COMPUTER SYSTEMS
• Supercomputer.
– Offers the fastest processing speeds and performs the
most complex calculations.
• Mainframe computer.
– Provides multi-user computing to large organizations
for tasks such as managing extensive databases,
financial transactions, and communications.
• Personal computer.
– Provides computing to a single user performing
multiple tasks.
56
COMPUTER PLATFORM
• Platform is a combination of hardware and
operating system.
– Windows/PC platform.
– Macintosh platform.
– Mobile Computing platform.
• Cross-platform compatibility.
– Ability of an application to run on different hardware and
operating systems.
• Adobe’s Acrobat .pdf files can be opened on Windows or Mac
OS based computers.
– The WWW provides a cross-platform computing
experience.
57
COMPUTER HARDWARE BASICS
SYSTEM UNIT and PERIPHERALS at
work.
58
SYSTEM UNIT
• Contains the components used to electronically
process and store data.
– Central Processing Unit.
– Primary memory.
– Expansion slots.
– System board circuitry.
59
CENTRAL PROCESSING UNIT (CPU)
• Consists of millions of integrated transistors that
execute program instructions and manipulate
data.
• Sets of transistors include:
– Control Unit
– Arithmetic Logic Unit
– Registers
– Cache.
View IT
Intel explains
the future for
transistors on
the CPU.
60
CPU AT WORK
• Processing data and instructions is
systematically executed in a machine cycle.
• Four steps in the cycle:
–
Fetch
– Decode
– Execute
– Store.
Figure 3.3
61
CPU FEATURES
• Clock speed
– Rate the CPU carries out basic instructions.
– Measured in megahertz (MHz) or gigahertz (GHz).
• Word size
– Number of bits the processor can manipulate in
one machine cycle.
– 64 bit processor can execute more data than a 32
bit processor.
62
CPU FEATURES
• Bus width
– The width of the electronic pathway that moves
data and instructions to the processor.
– A bus 64 bits wide carries more data than a bus
16 bits wide.
• Pipelining
– Method to increase processing speed by launching
more than one instruction in a single machine
cycle.
63
CPU FEATURES
• RISC
– Reduced Instruction Set Computer chips eliminate
complex embedded microcode.
• Multi-processing
– Combination of multiple processors to execute
instructions simultaneously.
64
APPROACHES TO Multi-Processing
• Multiple processors
– CPU + graphics co-processor.
• Multi-core processors
– Two or more logic cores on a single CPU chip to
execute different tasks.
• Parallel processing
– Linking multiple processors together to operate
simultaneously on the same task.
65
PRIMARY MEMORY
• Electronic storage locations for data and
instructions directly addressed by the CPU.
• Random Access Memory (RAM)
– Volatile storage area for operating system, software
applications, and user data.
– Capacities are measured in megabytes or gigabytes on
personal computers.
• Read Only Memory (ROM)
– Non-volatile electronic storage for frequently used
instructions such as the computer’s boot sequence.
66
CACHE MEMORY
• High speed electronic storage to optimize the
performance of the CPU.
– Reduces time to fetch data and instructions from RAM
storage.
• Level 1 or Primary Cache stores data and
instructions on the CPU chip.
• Level 2 Cache positioned between the CPU and
RAM.
• Capacities of cache vary.
– Total amounts are not part of RAM capacity.
67
SYSTEM BOARD
• Electronic circuit board at the base of the
system unit.
• Manages flow of electronic bits to:
– CPU
– RAM
– Expansion slots
– Video card
– Analog – Digital converters
– I/O interface ports.
68
HARDWARE INTERFACE
• Point of union between the system board and
peripheral devices.
• Data flows to the system board in
– Parallel transmission or
– Serial transmission.
69
INTERFACE PORTS
• Ports are external to the system unit.
– Peripherals are plugged into the ports.
• Common ports include:
– VGA or SVGA
– USB
– IEEE 1394 (FireWire)
– Thunderbolt
– Audio input/output
– Network port.
70
USB, Firewire, & Thunderbolt
• Offers Plug and Play performance.
• Supports a daisy-chain bus of multiple devices.
• Accepted on PCs and Macs.
• Has hot-swappable capability.
• Powered through the interface port.
– No more “wall warts.”
• Thunderbolt advantages:
– Higher transfer rates
– Eliminates need for separate video port
– Increases power to peripheral devices.
71
PERIPHERAL DEVICES
Hardware components to input, output,
store data and applications for the
processor.
With the miniaturization of today’s mobile
computing devices, the peripherals may not
seem so distant from the system processor.
72
SECONDARY STORAGE
• Holds data and instructions outside the
system unit for long periods of time.
• Advantages over primary storage:
– Nonvolatile storage
– Expandable
– Portable
– Inexpensive.
• Options include magnetic, optical, solid-state
storage.
73
SECONDARY STORAGE
• Five Main Uses
– Saving data during edit process.
Storage Devices
– Backup data and applications.
Hard drive
– Distribute data and applications.
Zip drive
Portable hard drive
Flash or thumb drive
– Transport data and applications.
– Archive data and applications.
CD drive
DVD drive
Magnetic tape drive
74
MAGNETIC STORAGE
• Bits are stored in magnetic form on disk
platters or magnetic tape.
• Data stored in addressable tracks and sectors
defined by the operating system.
– Track — circular paths
– Sector — pie shaped logical divisions of the track.
75
MAGNETIC STORAGE
• Hard Drives contain rigid platters mounted on a
spindle.
– Motor rotates the platters.
– Access arm with read/write head moves between
the platters.
– Data is stored on top
and bottom of each platter.
76
HARD DRIVE PERFORMANCE
• Storage capacity
– Measured in gigabytes or terabytes.
• Access time
– Measured in milliseconds, the time to locate data on
the platter.
• Transfer rate
– Measured in bytes, the speed of data transfer from
the platter to RAM.
77
MAGNETIC OPTIONS
•
•
•
•
•
Fixed internal hard drive.
Portable hard drive.
Cartridge drive.
RAID drive.
Magnetic tape drive.
78
MAGNETIC STORAGE
• Benefits:
– Large storage capacity
– Fast access to data
– Economical.
FYI:
• Challenges:
– Limited durability
– Easily damaged.
The projected cost
of a gigabyte of
magnetic storage
in 2016 is .01
cents.
79
OPTICAL STORAGE
• Compact Disc (CD) first used to replace vinyl
records in music industry.
– Stored digital music for permanent, high fidelity
recordings.
– Capacity set at 74 minutes of digital audio.
FYI:
Disc refers
to optical
storage.
Disk denotes
magnetic
storage.
80
LASER BEAMS
• Amplified light energy.
• When focused on a shiny surface, the beam reflects back to a photo
detector.
• Disc surface is “stamped” with pits and lands.
– Pits — indentations on surface.
– Land — flat area on surface.
• Digital code is read as variations in the reflection intensity.
81
LASER ADVANTAGES
• High capacity storage.
– Pits = .83 microns long and .5 microns wide.
– Data stored in a continuous spiral from inside to
outside edge of disc.
• Durable data.
– Pits and lands are pressed into a platter and
coated with lacquer material.
– Data is encoded with error detection/correction to
prevent damaged data.
82
OPTICAL RECORDING
• Data is organized
in:
– Tracks —
addressing scheme
on CD.
– Frame — physical
format of the data.
• 58 frames form a
sector on CD-ROM
or 2048 bytes of
data code.
– Sessions — single
recorded segment
on CD.
83
Compact Disc Formats
• Standard physical size.
– 120 mm, 15mm center hole, 1.2 mm thick.
– Led to rapid development of drives to accept all
CD formats.
• CD-DA (Digital Audio format).
• CD-ROM (Read-Only format).
• CD-R (Recordable format).
• CD-RW (Re-Writable format).
84
OPTICAL DRIVE
• Laser head moves along rails to position the
laser lens.
• Light reflects back to a photo detector.
• Motor spins the disc.
• Data is read using:
– CLV — Constant Linear Velocity
– CAV — Constant Angular Velocity.
85
DIGITAL VERSATILE DISC (DVD)
• Optical storage that uses:
– More precise laser light
– Multi-layer storage
– New video compression methods
– Improved error detection and correction.
• Result.
– Higher storage capacity than compact disc
• 650MB on CD (74 minutes of music)
• 17GB on DVD (8 hrs of video).
86
DVD FEATURES
• More precise laser beam reads smaller pits.
– .40 microns wide vs .83 microns on CD
– Smaller pits = more data capacity.
• Multi layer storage.
– Two reflective layers per side
– Each layer stores 4.7GB data.
FYI: Laser
Wavelength
compared.
CD = 780
nanometers.
DVD = 650
nanometers.
Blu-ray = 405
nanometers
87
Figure 3.16
88
DVD FEATURES
• MPEG2 compression.
– Compresses video at 40:1 ratio without
compromising video quality.
• Improved error detection/correction.
– CDs use 33% storage for ECC/EDC (error detection
and correction).
– DVDs reduce this to 13% of the storage.
89
DVD FORMATS
• Standards vary by player and data.
• DVD recordable formats:
– DVD-R: compatible with most players & drives
– DVD-RW: playable in many DVD drives and players
– DVD-RAM: Removable storage for computers.
90
BLU-RAY: Next Generation
• Optical storage based on blu-ray laser.
– Shorter wavelength (405nm).
• Massive storage capacity.
– Single layer can store 27GB of data.
• Can store 2 hours of high-definition video or
• 13 hours of standard video.
– Dual layer stores 50GB of data.
• Currently used for recording high definition video
and PlayStation 3 games.
91
SOLID-STATE STORAGE
• Computer storage with no moving parts.
• Devices are based on flash memory
technology.
– Contains a grid of cells, each with two transistors
separated by a thin layer of insulating oxide.
– The insulating oxide layer preserves information
with no need of external power.
92
SOLID-STATE STORAGE
• Benefits:
– Lightweight
– Small
– Low power requirements
– More durable than devices with movable parts.
• Disadvantages:
– More expensive than magnetic
storage
– Limited capacity
– Limited life expectancy.
FYI:
Labels for solid state
storage devices
include:
•USB drive
•Flash drive
•Thumb drive
•Memory stick
93
Storage in the Cloud
• The “cloud” is a metaphor for a network server
generally accessed via the Internet.
– Users maintain accounts to store, maintain, and manage
data remotely.
• Benefits of networked storage include:
– Portability
– Ubiquitous access.
• Challenges include:
– Security and reliability of the server.
– Access to data is dependent on the performance of a
remote server and network connections.
94
SECONDARY STORAGE &
Future of Digital Data
• Practical issues surrounding the migration of
data to secondary storage include:
– Effective and efficient data management.
– Enduring file formats over the years.
– Ability to access the data on the storage media
• Hardware requirements
• Software dependence.
– Data longevity.
95
INPUT DEVICES
• Capture and transmit data and instructions to
the system using for processing and storage.
• Categories:
– Keyboard
– Pointing devices
– Scanning devices
– Image capture
– Audio capture.
96
INPUT DEVICES
• Keyboard.
– Capture user text and commands.
• Pointing device.
– Relies on graphic interface to click or select the input.
– Devices include:
• Fingers
• Mouse
• Pointing stick
• Stylus
• Touch screens
• Touch pads
• Trackball.
FYI:
The Wii Remote
is also a pointing
device for the
popular game
console.
97
INPUT DEVICES: SCANNER
• Captures text or graphics using a light-sensing
device called a Charge-Coupled Device (CCD).
• Types of scanners include:
– Flat bed
– Hand held
– Sheet fed
– Slide.
• Scanner quality depends on:
– Spatial resolution
– Color resolution (bit depth).
98
SCANNER Settings
• Spatial Resolution (dpi).
– Depends on use of image.
• 72 dpi for computer display.
• 300 dpi for printer output.
• Color resolution (bit depth).
– 8 bit setting confines color range to 256.
– Grayscale setting uses black, white and shades of gray.
• Scaling.
– Set the size larger or smaller before the scan.
• Tonal quality.
– Adjust brightness and contrast based on preview of scan.
99
SCANNER & OCR
• Optical Character Recognition is a process that
converts printed text into an editable word
processed digital file.
– OCR software analyzes the image of a character
and translates it to an ASCII code of the character.
• OCR quality depends on software, quality of
printed text, and type of paper being scanned.
– Extensive editing may be required to remove stray
characters or misinterpreted text.
100
DIGITAL CAMERA
• Captures images in real time at the source.
• Benefits include:
– Instant review of image
– Re-capture the image if necessary
– High quality spatial and color resolution.
• Image file size depends on capture resolution (6 12 megapixel) and color depth (16 – 24 bit color) can
produce large file sizes.
• Images transferred to hard drive via memory card
or USB direct connection.
101
DIGITAL VIDEO (DV) CAMERA
• Video captured on built-in hard drive, minidigital tape, or DVD.
• Transferred to computer through FireWire
interface.
• Video editing software
enhances digital sequences.
102
DV CAMERA PERFORMANCE
• Method used to capture image.
– Single chip reproduce RGB color.
– 3-chip have separate CCD for Red, Green, Blue.
• Lens quality.
• Zoom quality.
– Optical zoom vs. digital zoom.
• Image stabilization.
• Preprogrammed modes.
– Lighting and weather conditions.
View IT:
Web source
and video on
choosing the
right video
camera.
103
SOUND CAPTURE
• Devices to transform analog waveforms to
digital files.
– Microphones
• External vs. internal
– CD & Tape players
– Digital Recorders.
104
GRAPHICS TABLET
• Flat drawing surface for freehand image
creation.
• User draws or traces image with a stylus then
enhances the image using software interface.
105
OUTPUT DEVICES
• Present processed data in a useful form.
• Devices include:
– Screen display
– Audio speakers
– Hard copy.
106
DISPLAY DEVICES
• Produce an image on a screen through a series
of individual pixels.
– Display quality is determined by spatial and color
resolution.
– Displays with 1024 X 768 spatial resolution have
more addressable pixels than 640 X 480
resolution.
– 24-bit color graphics display has richer colors than
16-bit color.
107
CRT DISPLAY
• Raster scanning technology generates a
display.
– Based on Cathode Ray Tube technology.
• Electronic signal scans
horizontal rows from
top to bottom of screen.
Figure
3.23
108
Figure 3.23
109
LCD & LED DISPLAY
• Use Thin Film Transistors (TFT)
– Assign a single transistor to each liquid cell to control
color and light.
• LCD displays use fluorescent lamp to project
through polarized liquid crystals.
• LED displays use light emitting diodes for brighter
backlighting and more
vibrant colors.
• LED’s are becoming commonplace on
laptop and desktop computers.
– They use less power
– Display brighter, richer colors.
110
SPEAKER SYSTEMS
• Speakers or headsets are plugged into the
soundboard where digital data is converted to
analog waveforms.
• Sound card circuitry performs four processes:
– Converts digital sound data into analog with DAC.
(digital to analog converter)
– Records sound in digital form with analog ADC.
– Amplifies signal.
– Creates digital sounds using a synthesizer.
111
PRINTERS
• Two basic printing technologies:
– Impact, print head makes contact …