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GEC Group of College’s
Dept. of Computer Sc. &Engg. and IT
Teaching Notes
IT – 602
COMPUTER GRAPHICS & MULTIMEDIA
Prepared by
Mr. Saurabh Garg
IT- 602 – Computer Graphics and Multimedia
Unit I
Introduction to Raster scan displays, Storage tube displays, refreshing, flickring,
interlacing, colour monitors, display processors resolution, working principle of dot
matirix, inkjet laser printers, working principles of keyboard, mouse scanner, digitizing
camera, track ball , tablets and joysticks, graphical input techniques, positioning
techniques, rubber band techniques, dragging etc.
Unit II
Scan conversion techniques, image representation, line drawing, simple DDA,
Bresenham’s Algorithm, Circle drawing, general method, symmetric DDA, Bresenham’s
Algorithm, curves, parametric function, Beizier Method, B-spline Method.
Unit III
2D & 3D Co-ordinate system, Translation, Rotation, Scaling, Reflection Inverse
transformation, Composite transformation, world coordinate system, screen coordinate
system, parallel and perspective projection, Representation of 3D object on 2D screen. Point
Clipping. Line Clipping Algorithms, Polygon Clipping algorithms, Introduction to Hidden
Surface elimination, Basic illumination model, diffuse reflection, specular reflection, phong
shading, Gourand shading ray tracing, color models like RGB, YIQ, CMY, HSV etc.
Unit IV
An Introduction – Multimedia applications – Multimedia System Architecture –
Evolving technologies for Multimedia – Defining objects for Multimedia systems –
Multimedia Data interface standards – Multimedia Databases.
Multimedia components, Multimedia Hardware, SCSI, IDE, MCI, Multimedia -Tools,
presentation tools, Authoring tools .
Unit V
Compression & Decompression – Multimedia Data & File Format standards :-TIFF, MIDI,
JPEG, DIB, MPEG,RTF, – Multimedia I/O technologies - Digital voice and audio – Video
image and animation–Full motion video – Storage and retrievaltechnologies.
UNIT-IV
What is multimedia?
Multimedia is the media that uses multiple forms of information content and information
processing (e.g. Text, audio, graphics, animation, video, interactivity) to inform or entertain the
user. Multimedia also refers to the use of electronic media to store and experience multimedia
content. Multimedia is similar to traditional mixed media in fine art, but with a broader
scope. The term "rich media” is synonymous for interactive multimedia.
In everyday life, multimedia is everything you hear or see, e.g. text in books, sound in music,
and graphics in pictures.
In computing multimedia is the presentation of information by a computer system using text,
sound and graphics.
Elements of Multimedia System
Multimedia means that computer information can be represented through audio, graphics,
image, video and animation in addition to traditional media(text and graphics).
Hypermedia can be considered as one type of particular multimedia application.
Characteristics of a Multimedia System
A Multimedia system has four basic characteristics:
•
Multimedia systems must be computer controlled.
•
Multimedia systems are integrated.
•
The information they handle must be represented digitally.
•
The interface to the final presentation of media is usually interactive.
Applications of Multimedia
Multimedia Architecture:
Applications
Graphical User Interface
Operating System
Multimedia Extensions
Software Drivers Multimedia Drivers Support
System Hardware (Multimedia enabled)
Add on Multimedia Devices & Peripherals
1. Applications: It should require absolutely no change to operate with a variety of hardware
interfaces.
2. GUI: It is designed primarily for windows managed by applications at fixed resolutions.
3. Multimedia Extensions: These are needed to support applications such as full motion video,
remote desktop etc.
4. Operating System: All multimedia capabilities integrate with standard user interfaces such as
MS Windows
5. Multimedia Drivers Support: Software device driver is needed for each of these special
devices to provide the interface from an application to device.
6. Software Hardware: Multimedia operation places tremendous demands of computing
performing and storage on system hardware.
7. Add on multimedia devices & peripherals: They include scanners, video cameras, VCRs
etc.
Multimedia Database Systems
• The multimedia database systems are to be used when it is required to administrate a huge
amounts of multimedia data objects of different types of data media (optical storage, videotapes,
audio records, etc.) so that they can be used (that is, efficiently accessed and searched)for as
many applications as needed.
• The Objects of Multimedia Data are: text, images. Graphics, sound recordings, video
recordings, signals, etc., that are digitalized and stored.
• Multimedia Data are to be compared in the following way: Medium Elements Configuration
Typical size Time dependent Sense
The need and efficiency of MM-DBS are to be defined by following requirements:
Basic service:
• To be used for multiple applications
• Not applicable as a real end-user system (like program interface)
Storage and retrieval of MM-Data:
For the Storage:
• input of MM objects
• composition (to multimedia objects) (example: authoring systems)
• Archive of data (in hardware and format independent way)
For the Retrieval:
• Support of complex search
• Efficiency (indices etc.)
• Evaluation (aggregation, filtering)
• Preview
• Also conversions (needed to gain or lead to hardware and format independence)
For the Update
• Only replace or also edit? (the complexity depends on).
Multimedia Database Systems have to be capable:
1. Support of multimedia data types, i.e. data types as data structures, including type of data and
operations
2. Capability to manage very numerous multimedia objects, store them and search for them
3. To include a suitable memory management system, to improve performance, high capacity,
cost optimization
4. Database system features:
• Persistency
• Transaction concept
• Multi-user capability
• Recovery
• Ad-hoc queries
• Integrity constrains (which leads to consistency)
• Safety
• Performance
5. Information retrieval features:
• Attribute-based search
• Content-based search
Integrity Constrains for MM-DB Applications
The following features are typical for MMDB:
• Unique, Primary-key Constraints
• Referential integrity
• Via foreign keys (RM)
• Via OIDs (OO)
• Existential integrity
• NOT NULL constraints
• Integrity rules (check clauses)
• Trigger
Specifically for OO:
• Pre- and post conditions for methods
• Constraints of the class hierarchy
• Partition conditions (Disjointness constraints)
Advantages of Multimedia Database Systems
• integrated administration of huge amounts of multimedia data
• optimized storage
• Efficient access
• manyfold complex search possibilities
• Referential integrity of links
• Transaction protected multiuser mode
• Recovery• etc.
Multimedia-DB applications
Fields of application:
• Static/passive:
Retrieval / Information / Archive
(Libraries, video on demand, information systems, press, hospitals)
Databases, information retrieval
• Static/aktiv
Education / Commercials/ Entertainment
(School, university, professional training, games, commercials)
CSE, Teach ware, Courseware, CBT,
• Dynamic/passiv
Writing / Publications/ Design
(Press, engineering, architecture)
Editors, layout generators, CAD-systems
• Dynamic/active
Controlling/Monitoring (Factories, traffic, weather forecast, military)
Process control systems
Components of Multimedia
The various components of multimedia are Text, Audio, Graphics, Video and Animation. All
these components work together to represent information in an effective and easy manner.
1) Text: Text is the most common medium of representing the information. In multimedia, text is
mostly use for titles, headlines, menu etc. The most commonly used software for viewing text
files are Microsoft Word, Notepad, Word pad etc. Mostly the text files are formatted with, DOC,
TXT etcextension.
2) Audio: In multimedia audio means related with recording, playing etc. Audio is an important
component of multimedia because this component increases the understandability and improves
the clarity of the concept. Audio includes speech, music etc. The commonly used software for
playing audio files are:
i) Quick Time
ii) Real player
iii) Windows Media Player
3)Graphics: Every multimedia presentation is based on graphics. The used of graphics in
multimedia makes the concept more effective and presentable. the commonly used software for
viewing graphics are windows Picture, Internet Explorer etc. The commonly used graphics
editing software is Adobe Photoshop through which graphics can be edited easily and can be
make effective and attractive.
4) Video: Video means moving pictures with sound. It is the best way to communicate with each
other. In multimedia it is used to makes the information more presentable and it saves a large
amount of time. The commonly used software for viewing videos are:
i) Quick Time
ii) Window Media Player
iii) Real Player
5)Animation: In computer animation is used to make changes to the images so that the sequence
of the images appears to be moving pictures. An animated sequence shows a number of frames
per second to produce an effect of motion in the user's eye. Some of the commonly used software
for viewing animation are:
i) Internet Explorer
ii) Windows Pictures
iii) Fax Viewer
Multimedia Hardware
Keyboards
Input devices enable users to input different kinds of data from text through to video into a
computer. Keyboards have not changed in layout since the QWERTY arrangement of the
nineteenth century although there have been several attempts at improving its layout. The design
of the keyboards has improved with cordless and ergonomically contoured keyboards like that
shown in Figure
Pointing devices
There are a range of pointing devices used in multimedia development and delivery. The classic
pointing device is the mouse which is now available cordless and is based on an optical sensor
rather than a rolling ball. Multimedia developers who are engaged in image or video editing may
wish to use more sophisticated pointing devices like a tracker ball or tablet. Figure shows a state
of the art tracker ball which gives developers finer control over the position of the pointer
without moving their hands.
The other pointing device used by developers is the digitizing tablet as shown in Figure. Either a
special pen or a mouse is used as the pointing device allowing developers to map the dimensions
of the tablet to the dimensions of the screen so that extreme points of the tablet match the
extreme points of the screen. Multimedia developers can place pictures onto the digitizing tablet
and ‘trace’ them if they need to.
Sound recording equipment
The use of sound in its various forms is a component of a multimedia
application and the
quality of the recording equipment is important in determining the final quality of the sound.
Sound recording equipment ranges from a simple tape cassette recorder for low budget amateur
sound productions to a fully equipped professional recording studio. The essential pieces of
hardware for recording sound are microphones or musical instruments for creating the sound
source, portable recording equipment like a digital audio tape (DAT) recorder for use outside a
studio, a multitask mixing console for editing and mixing various sources of sound and another
storage device like a DAT recorder. DAT recorders enable sound to be recorded at sampling
rates up to 96 KHz and 16 bits per sample. The medium for the recording, editing and capture of
music is generally undertaken using the MIDI data format and today most electronic instruments
and equipment associated with music support it
Video recording equipment
The hardware used in professional video production is beyond the scope of this book so we focus
on the kind of equipment that could be used by a small independent multimedia design company
or home users. Basic video recording equipment includes either an analogue or digital video
camera and a video capture card installed in a desktop computer. Video capture cards are
different to graphic display cards which are not capable of video capture. Although many video
experts still prefer using analogue cameras, digital video cameras are becoming more standard
offering 6Mb/s data rate or up to 30 frames per second at a resolution of 720 by 480 pixels. Once
a piece of video has been recorded it needs to be captured; digital video cameras can be
connected directly to one of the USB or serial ports on the desktop computer but analogue video
needs to be captured via a video capture card. Video capture cards receive analogue video signals
through one of their ports and sample it at a frequency up to 30 frames per second, a resolution
of 768 by 576 pixels and a sample size of 24 bits per pixel. Video capture requires high
specification desktop computers with a fast, high capacity hard disk drive to cope with the input
video data.
Image scanners
The last type of input device used in multimedia development which you should be aware of our
image scanners. Scanners enable developers to digitize hard copies of pictures and photographs
ready for editing and inclusion in multimedia projects. Standard flatbed scanners see in figure,
are available in up to A3 size and scan up to 2400 dots per inch (dpi) with a colour depth of up to
48 bits per pixel
Monitors
The most important output device for multimedia development and delivery is the monitor. Thus
the quality of monitors and the graphic display cards that drive them are important considerations
for multimedia developers. Multimedia developers need to use large 17’’ or 19‘‘ (measured
diagonally across the screen) monitors in order to have room to display the multimedia
application under development and the various dialogue boxes of the authoring tools. Some
multimedia developers use two monitors that are driven using special graphics cards so that they
can see the multimedia application on one screen and have the tools displayed on the other.
Speakers
Another crucial output device for multimedia applications are the speakers which provide the
sound outputs. Speakers are driven by sound cards as explained in the last section. Most sound
cards support the SoundBlaster standard developed by Creative Labs and the General MIDI
standard for sound reproduction. Speakers used with desktop computers usually require their
own power source and have built-in amplifiers.
Printers
The last type of output device used in multimedia is the printer. For multimedia development it is
important to have a high quality colour printer to show screen shots to clients and for discussing
particular elements of a multimedia project. It is impossible for a printer to exactly match the onscreen colours, however they are helpful in seeing the general look and feel of an application.
There are two types of colour printer - laser and inkjet. Currently a top of the range inkjet printer
is capable of outputting about 1.5 pages per minute at a quality of 1200 by 600 dpi and a similar
priced colour laser can output four pages per minute at a quality of 600 by 600 dpi. The new
inkjet and colour laser printers allow you to change each of the colour cartridges (cyan, magenta,
yellow and black) separately. The latest inkjet printers also allow you to purchase each of the
colour print heads and associated ink cartridges separately hence reducing the cost of printing.
Currently colour laser printers have a lower cost per page than an equivalent inkjet printer.
Multimedia Hardware
The hardware required for multimedia can be classified into five. They are
1. Connecting Devices
2. Input devices
3. Output devices
4. Storage devices and
5. Communicating devices
Connecting Devices
Among the much hardware – computers, monitors, disk drives, video projectors, light valves,
video projectors, players, VCRs, mixers, sound speakers there are enough wires which connect
these devices. The data transfer speed the connecting devices provide will determine the
faster delivery of the multimedia content.
The most popularly used connecting devices are:
1.
SCSI
2.
USB
3.
MCI
4.
IDE
5.
USB
SCSI
SCSI (Small Computer System Interface) is a set of standards for physically
connecting and transferring data between computers and peripheral devices. The SCSI
standards define commands, protocols, electrical and optical interfaces. SCSI is most
commonly used for hard disks and tape drives, but it can connect a wide range of other
devices, including scanners, and optical drives (CD, DVD, etc.).
SCSI is most commonly pronounced "scuzzy".
Since its standardization in 1986, SCSI has been commonly used in the Apple
Macintosh and Sun Microsystems computer lines and PC server systems. SCSI has never been
popular in the low-priced IBM PC world, owing to the lower cost and adequate performance
of its ATA hard disk standard. SCSI drives and even SCSI RAIDs became common in PC
workstations for video or audio production, but the appearance of large cheap SATA drives
means that SATA is rapidly taking over this market.
Currently, SCSI is popular on high-performance workstations and servers. RAIDs on
servers almost always use SCSI hard disks, though a number of manufacturers offer SATAbased RAID systems as a cheaper option. Desktop computers and notebooks more typically
use the ATA/IDE or the newer SATA interfaces for hard disks, and USB and FireWire
connections for external devices.
Media Control Interface (MCI)
The Media Control Interface, MCI in short, is an aging API for controlling
multimedia peripherals connected to a Microsoft Windows or OS/2 computer. MCI
makes it very simple to write a program which can play a wide variety of media files and even
to record sound by just passing commands as strings. It uses relations described in Windows
registries or in the [MCI] section of the file SYSTEM.INI.
The MCI interface is a high-level API developed by Microsoft and IBM for
controlling multimedia devices, such as CD-ROM players and audio controllers.
The advantage is that MCI commands can be transmitted both from the programming
language and from the scripting language (open script, lingo). For a number of years, the MCI
interface has been phased out in favor of the DirectX APIs.
MCI Devices
The Media Control Interface consists of 4 parts:
1.
2.
3.
4.
AVIVideo
CDAudio
Sequencer
WaveAudio
Each of these so-called MCI devices can play a certain type of files e.g. AVI Video plays avi
files, CDAudio plays cd tracks among others. Other MCI devices have also been made
available over time.
IDE
Usually storage devices connect to the computer through an Integrated Drive Electronics
(IDE) interface. Essentially, an IDE interface is a standard way for a storage device to connect
to a computer. IDE is actually not the true technical name for the interface standard. The
original name, AT Attachment (ATA), signified that the interface was initially developed for
the IBM AT computer.
IDE was created as a way to standardize the use of hard drives in computers. The basic concept
behind IDE is that the hard drive and the controller should be combined. The controller is a
small circuit board with chips that provide guidance as to exactly how the hard drive stores and
accesses data. Most controllers also include some memory that acts as a buffer to enhance hard
drive performance.
Before IDE, controllers and hard drives were separate and often proprietary. In other words, a
controller from one manufacturer might not work with a hard drive from another
Manufacturer. The distance between the controller and the hard drive could result in poor
signal quality and affect performance. Obviously, this caused much frustration for computer
users.
IDE devices use a ribbon cable to connect to each other. Ribbon cables have all of the
wires laid flat next to each other instead of bunched or wrapped together in a bundle. IDE
ribbon cables have either 40 or 80 wires. There is a connector at each end of the cable and
another one about two-thirds of the distance from the motherboard connector. This cable
cannot exceed 18 inches (46 cm) in total length (12 inches from first to second connector, and
6 inches from second to third) to maintain signal integrity. The three connectors are typically
different colors and attach to specific items:
1. The blue connector attaches to the motherboard.
2. The black connector attaches to the primary (master) drive.
3. The grey connector attaches to the secondary (slave) drive.
Enhanced IDE (EIDE) — an extension to the original ATA standard again developed
by Western Digital — allowed the support of drives having a storage capacity larger than 504
MiBs (528 MB), up to 7.8 GiBs (8.4 GB). Although these new names originated in
branding convention and not as an official standard, the terms IDE and EIDE often appear
as if interchangeable with ATA. This may be attributed to the two technologies being
introduced with the same consumable devices — these "new" ATA hard drives.
With the introduction of Serial ATA around 2003, conventional ATA was retroactively
renamed to Parallel ATA (P-ATA), referring to the method in which data travels over wires
in this interface.
Presentation Tools
Presentation is the process of presenting the content of a topic to an audience. A
presentation program is a computer software package used to display
information, normally in the form of a slide show. It typically includes three major
functions: an editor that allows text to be inserted and formatted, a method for inserting
and manipulating graphic images and a slide-show system to display the content.
There a r e m a n y d i f f e r e n t t y p e s o f p r e s e n t a t i o n s i n c l u d i n g p r o f e s s i o n a l
(work-related), education, worship and for general communication
The most commonly known presentation program is Microsoft PowerPoint, although
there are alternatives such as OpenOffice.org Impress and Apple's Keynote. In
general, the presentation follows a hierarchical tree explored linearly (like in a table of
content) which has the advantage to follow a printed text often given to participants.
Adobe Acrobat is also a popular tool for presentation which can be used to easily link
other presentations of whatever kind and by adding the faculty of zooming without loss
of accuracy due to vector graphics inherent to PostScript and PDF.
KEYNOTE : Keynote is a presentation software application developed by Apple Inc. and a
part of the iWork productivity suite (which also includes Pages and Numbers) sold by
Apple
Impress : A presentation program similar to Microsoft PowerPoint. It can export
presentations to Adobe Flash (SWF) files allowing them to be played on any computer
with the Flash player installed. It also includes the ability to create PDF files, and the
ability to read Microsoft PowerPoint's
.ppt format. Impress suffers from a lack of ready-made presentation designs.
However, templates are readily available on the Internet.
Microsoft PowerPoint: This is a presentation program developed by Microsoft. It is part of
the Microsoft Office system. Microsoft PowerPoint runs on Microsoft Windows and the
Mac OS computer operating systems.