Introduction, History Application in different fields like CAD, schematic capture, medicine, art etc. Hardware concepts 2-D and 3-D algorithms Line drawing, viewing transformations, other transforms (scaling, rotation, translation) Curve Modeling Mathematics of generation of parametric cureve like Bazier, Spline, Hermite 3D Object Modeling Visible Surface Detection and Surface Rendering Introduction to Animation Text Book Computer Graphics C Version – Hearn & Baker

1. Introduction To Computer Graphics
Prepared By:Er. Loknath Regmi
Computer Graphics

2. Course Overview
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 Introduction, History
 Application in different fields like CAD, schematic capture, medicine, art etc.
 Hardware concepts
 2-D and 3-D algorithms
 Line drawing, viewing transformations, other transforms (scaling, rotation,
translation)
 Curve Modeling
 Mathematics of generation of parametric cureve like Bazier, Spline, Hermite
 3D Object Modeling
 Visible Surface Detection and Surface Rendering
 Introduction to Animation
 Text Book
 Computer Graphics CVersion – Hearn & Baker

3. Computer Graphics
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A sub-field of computer science which studies method for
digitally synthesizing and manipulating visual content.
Are texts and sounds graphics ???
No (wikipedia); but text??
Generally refers to (Ref:Wikipedia):
Representation and manipulation of pictorial data by computer
Various technologies used to create and manipulate such pictorial data
The image so produced

4. Image Processing Vs
Computer Graphic
 Computer Graphics
 a mathematical modeling
deals about synthesis, manipulation, processing, and
storage of image of an object
 a complete package on generation and modeling of
graph
 deals about generation of math mathical model
 Image Processing
 not explain about synthesis of image
 explain manipulation and processing of existing image
 use the mathematical model for processing of imagePrepared By:Er. Loknath Regmi

5. History of Computer Graphics
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 Late 1950’s –Whirlwind computer (MIT) and SAGE (Semi Automatic Ground Environment);
an automated control system to bombard enemy
 Used CRT and light pen for user interactive environment
 1959 –TX-2 (MIT’s Lincoln Laboratory); first interactive interface computer system using
light pen and bank switches
 1960 –William Fetter
 Introduced phrase “Computer Graphics”
 Boeing man (Fetter called it First Man) for human figure simulation to describe different user
environment
 Mid 1960’s – MIT activities in computer graphics field promoted early computer graphics
industries likeTRW, General Electric, IBM
 End 1960’s – organization, conferences, graphics standards and publications
 1969 – ACM initiated Special Interest Group In Graphics (SIGGRAPH)

6. History of Computer Graphics
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1970’s – powerful PCs to draw basic and complex shapes
1980’s – artists and graphics designers preferred to use
Macintosh and PCs
Late 1980’s – 3-D computer graphics with SGI (Silicon
Graphics) computers
1990’s onwards – 3D graphics in gaming, multi media and
animation, GUI

7. Applications Areas of CG
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Display of Information
Design
Simulation
Computer Art
Entertainment

8. Display of Information
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 Graphics for Scientific, Engineering, and Medical Data
Nebla Medical Image

9. Design
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Graphics for Engineering and Architectural System
Design of Building,Automobile,Aircraft, Machine etc.
AutoCAD
2002
Interior Design

10. Simulation
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 Computer-Generated Models of Physical, Financial and
Economic Systems for Educational Aids
Flight Simulator Mars Rover Simulator

11. Computer Art
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 Graphics for Artist
Metacreation Painter

12. Entertainment
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 Graphics for Movie, Game,VR etc.
Final Fantasy
Online Game

13. What’s Our Scope?
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Not aTutorial on Commercial Software
3DMax, Maya, Photoshop, etc.
Not about Graphics Business
3D online-game, E-commerce, etc.
Graphics = Algorithm forVisual Simulation
Imaging, Modeling, Rendering,Animation

14. Pixels
The computer stores and displays pixels, or picture elements.
A pixel is the smallest addressable part of the computer screen.
A pixel is stored as a binary code representing a colour.
The code for a pixel can have between 1 and 32 bits of binary
code.
Here is the Photoshop logo at normal size.
 Here it is enlarged 400% so that you can see the individual pixels.
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15. Pixel Depth
Pixel Depth describes the number of bits used to store each pixel.
The greater the pixel depth, the more colours a pixel can have.
Colour graphics vary in realism depending on resolution and pixel
depth.
The greater the pixel depth, the bigger the file.
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16. Examples of Pixel Depth
Monochrome
Monochrome graphics have one-bit pixel depth. (pure black or pure
white)
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17. Examples of Pixel Depth
Gray-Scale
Gray-Scale graphics have more bit-depth
(No colours besides black, white and grey)
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18. Examples of Pixel Depth
8 Bit Colour
 8 bits per pixel provides 256 colour
choices
(Typical of the web - that’s why web graphics need some
skilful preparation)
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19. Examples of Pixel Depth
 24 or 32 bits per pixel provides thousands or millions of
colour choices. (Typical of graphics and games software)
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20. Resolution
Resolution refers to the density of dots on the screen or
printed image and directly affects quality
The higher the resolution, the less jagged the image.
Resolution is measured in DPI (Dots per Inch)
(The printing industry is largely unmetricated and still
uses inches because printing measures such as the Point
(1 72nd of an inch) do not easily convert to metric
units.)
The higher the resolution, the better the potential
output.
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21. Typical Resolutions
Screens generally operate at around 72-100 dpi
Printed images range from 300 to 2400 dpi
Resolution affects the file size of an image.
The higher the resolution, the bigger the file.
The visible resolution is limited to the maximum
possible on the output device (screen or printer).
No matter how high the resolution of a photograph, it
will show at the resolution of your screen or printer.
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22. File Types
 There are many kinds of graphics file formats and this is
a specialised area and a bit complicated.
Examples : bmp GIF JPEGTIFF PICT Raw
For most applications involving photographic images,
use the JPEG file format (Joint Photographic Experts
Group)
For graphics or paint type files use GIFs
(Graphical Interchange Format)
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23. JPEG
The JPEG format can be used by most applications and
all browsers
It has very good compression algorithms
It stores a good quality image in a remarkably small file
with little or no loss of quality
JPEG offers 10 quality levels with correspondingly
smaller files and greater losses in quality
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24. GIF
You should choose a GIF format instead of JPEG when
You have a graphic with only a few colours such as a logo or
icon
You want to create an image with some transparent parts for a
web page
You want the smallest possible file size with totally lossless
compression
You want to combine a few images together into an animation
You want to save text as a graphic
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