The document provides an overview of computer graphics, including its mathematical and computational foundations for synthesizing and manipulating visual content. It covers key concepts such as image representation, rasterization, bitmap vs vector graphics, and applications in various fields like digital art and medical imaging. Additionally, it discusses display devices like cathode ray tubes and the graphic rendering pipeline.

1. Basics of Computer Graphics
Dheeraj S. Sadawarte
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2. Introduction
• Field of science concerned with digitally
synthesizing and manipulating the visual content.
– creating,
– Storing
– Displaying
– manipulating images
• Focus on mathematical & computational
foundations of image generations .
• Manipulation of visual & geometric information
using computational techniques.
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3. Images and object
• Image is a representation of an object on a
computer
• Symbolic representation other than the text
• 2D array of data with values at each element
of the array related to a color
• Objects are real entities defined in 3D world
co-ordinates.
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4. Image Representation
• Pictures are represented as a collection of
discrete picture element called PIXELS.
• It is the smallest addressable screen element.
• resolution is the number of pixels contained on
a display screen.
• It expressed in terms of the number of pixels on
the horizontal axis and the number on the
vertical axis.
• The process of determining the appropriate
pixels for representing pictures or objects is
called RASTERIZATION.
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5. Rasterization and Scan Conversion
• Rasterization is the task of taking an image
described in a vector graphics format (shapes)
and converting it into a raster image (pixels or
dots) for output on a video display or printer,
or for storage in a bitmap file format
• Scan conversion: The process of representing
continuous pictures as graphical object(as a
collection of discrete pixel) is called scan
conversion.
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6. Image Representation
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7. Basic graphic pipeline
• Object in a real world are expressed with respect
to a world co ordinate system
• The world is then projected into a view plan from
a view point
• Z axis determines the view direction
• Window specifies the area of interest
• View volume is the infinite volume swept by the
rays
• Near and far clipping plane
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Dheeraj S Sadawarte
https://dheerajsadawarte.blogspot.com

8. Bitmap and vector based graphics
BITMAP (raster) VECTOR BASED
• Composed of pixels
• Created and edited in photo
or paint program
• Images are mapped to a grid
or an array of pixels
• Not easily scalable
• Used in photorealistic images
involves complex variation
• The larger we display a
bitmap, the jagged it appears
• Composed of paths
• Created and edited in
software like CoralDraw and
Adobe Illustrator
• Images have smooth edges
and create curves or shapes
• Good for precise illustrator
but not as good as bitmap
• Easily scalable due to the use
of mathematical formula
• A vector image remains
smooth in any size
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Dheeraj S Sadawarte
https://dheerajsadawarte.blogspot.com

9. Application of computer graphics
• Special effects-illusions used in film, television industries
to simulate the imagined events in a story.
• Visual effects-involves integration of live-action footage
with computer generated elements in order to create
scenarios which look realistic.
• Digital art-an art created on a computer in a digital form
• Video games: gaming and animation industry
• Computer aided design-used by civil, mechanical &
electronic engineers to build the models of buildings,
bridges or circuit boards
• Medical imaging-used in molecular biology to study the
model of the genes
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Dheeraj S Sadawarte
https://dheerajsadawarte.blogspot.com

10. Display device
• Display device is a device for presentation of
information such as images or a text for visual
display.
• Eg:CRT(Cathode ray tube)
• It is a specialized vacuum tube in which
images are produced when an electron beam
strikes a phosphorescent surface.
• Heat is supplied to the cathode by passing
current through a heater element. The
cathode is a cylindrical metallic structure
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11. Cathode Ray Tube
• Cathode ray tube:
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12. You can
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