Page 60 - DCAP504_Computer Graphics

Mithilesh Kumar Dubey, Lovely Professional University Unit 5: Scan Conversion II

Unit 5: Scan Conversion II

CONTENTS
Objectives
Introduction
5.1 Polygon
5.2 Region Filling
5.3 Glyph

5.4 Aliasing and Anti-aliasing
5.5 Summary
5.6 Keywords
5.7 Self Assessment
5.8 Review Questions
5.9 Further Readings

Objectives

After studying this unit, you will be able to:
• Explain scan conversion of polygon
• Discuss region filling

• Define glyphs
• Explain aliasing and anti-aliasing
Introduction

Scan conversion is the process of converting vertical or horizontal scan frequency of video signals for
different purposes and applications. The scan converters are the devices that perform the scan
conversion. In the previous unit, we have already discussed the two different methods of the scan
conversion process. They are:
1. Analog Method: This type of conversion is done using delay cells that are useful for analog video.
2. Digital Method: In this method, the picture given in application program is digitized into a pixel
values that are stored in the frame buffer.

We also discussed the method of scan converting circle, line, ellipse, and arcs and sectors. This unit
discusses the method of scan converting the polygon. This unit also gives an overview on region filling,
glyphs, aliasing and anti-aliasing.
5.1 Polygon

A polygon is a closed 2D object or figure that has three or more sides. Polygons are named based on the
number of sides it has.

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