## What is transformation? Type of transformation

by Dinesh Thakur Category: Two Dimensional Transformations

What is transformation? In  many  cases  a  complex  picture  can  always  be  treated as  a  combination  of  straight line, circles, ellipse etc., and if we are able to generate these basic figures, we can also generate combinations of them.  Once we  have drawn these pictures, the  need arises  to transform these pictures.

## Explain the line drawing algorithm for DDA.

by Dinesh Thakur Category: Two Dimensional Transformations

Digital Differential Analyzer is a scan conversion line algorithm based on calculating either dy or dx. We sample the line at unit intervals in one coordinate & determine corresponding integer values nearest to the line path for the other coordinate.

## Write a note on text clipping.

by Dinesh Thakur Category: Two Dimensional Transformations

There are several techniques that can be used to provide text clipping in a graphics package. The clipping technique used will depend on the methods used to generate characters and the requirements of a particular application.

## What is clipping? Explain any one clipping algorithm.

by Dinesh Thakur Category: Two Dimensional Transformations

Any procedure that identifies those portions of a picture that are either inside or outside of a specified region or space is known as clipping.

by Dinesh Thakur Category: Two Dimensional Transformations

Both methods are used in color CRT monitors. Beam penetration method is used for random scan monitors. In beam penetration two layers of phosphor red and green are coated inside CRT screen, the display of color depend on how far electron excites outer red layer, then green layer. This method can produce four colors i.e red ,green, orange, yellow. This is less costly method as compared to shadow mask.

## Sutherland-Hodgeman Polygon Clipping

by Dinesh Thakur Category: Two Dimensional Transformations

In polygon clipping, we use an algorithm that generates one or more closed areas that are then scan converted for the appropriate area fill. The output of a polygon clipper should be a sequence of vertices that define the clipped polygon boundaries. We can correctly clip a polygon by processing the polygon boundary as whole each window edge.

## Differentiate between raster scan and random scan displays.

by Dinesh Thakur Category: Two Dimensional Transformations

The most common form of graphics monitor employing a CRT is the raster scan display, based on television technology. In a raster scan system, the electron beam is swept across the screen, one row at a time from top to bottom. As the electron beam moves across each row, the beam intensity is turned on and off to create a pattern of illuminated spots. Picture definition is stored in a memory area called the refresh buffer or frame buffer.

## What is image processing? Explain its working principle.

by Dinesh Thakur Category: Two Dimensional Transformations

It is a technique to modify or interpret existing pictures, such as photographs. Two principal applications of image processing are:

## What is half-toning effect?

by Dinesh Thakur Category: Two Dimensional Transformations

Continuous-tone graphs are reproduced for publication in newspapers, magazines & books with a printing process called half toning, & the reproduced pictures are called halftones. For a black and white photograph, each intensity area is reproduced as a series of black circles on white background.

## What are the various transformations possible in 2-D? Explain any 3 of them.

by Dinesh Thakur Category: Two Dimensional Transformations

1. Translation: A translation is applied to an object by repositioning it along a straight line path from one coordinate position to another. We translate a 2-D point by adding translation distances tx & ty, to the original coordinate position ( x, y) to move the point to a new position (x? , y?)
X? = x + tx , y? = y + ty.

Page 8 of 10

Dinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.