Raster scan and random scan in computer graphics pdf

The key difference between raster scan and random scan, in raster scan electron beam, is swept across the screen, one row at a time, from top to bottom. Difference between random scan and raster scan display. A raster scan, or raster scanning, is the rectangular pattern of image capture and reconstruction in television. Computer graphics pdf computer graphics book pdf notes starts with the topics covering introduction of computer graphics.

The electron beam is swept across the screen, one row at a time, from top to bottom. Architecture of raster and random scan display devices, inputoutput devices. Random scan is a process in which the display is made by the electronic beam, which is directed, only to the points or division of the screen where the picture is to be drawn. Raster scan display has low resolution as picture definition is stored as a. Computer graphics is a branch of computer science that deals with graph, image and pictures. Random scan monitors draw a picture one line at a time.

In a raster scan system, the electron beam is swept across the screen. Contrasting in random scan displays the electron beam is directed to the parts of the screen where a picture is to be drawn. A system which follows raster scan displays is called raster scan system 2. The growth in the use of such methods has been dependent on rapidly decreasing memory prices and on the availability of cheap scan generating hardware from the tv industry. A graphics processor accepts graphics commands from the cpu and executes the graphics commands which may involve drawing into the frame buffer. Cs3162 introduction to computer graphics helena wong, 2000 4 2. A pixel is simply the smallest addressable element of a picture represented on a screen. As the electron beam moves across each row, the beam intensity is turned on and off to create a pattern of illuminated spots. Unlike a raster scan, a random scan doesnt have a set pattern, thus the name.

Raster scan and random scan display in computer graphics. Shekhat, ce department 2160703 computer graphics 1. Computer graphics tutorial application of computer graphics interactive and passive graphics graphic systems display processor cathode ray tube crt random scan vs raster scan color crt monitors direct view storage tubes flat panel display. Raster scan is the representation of images as a collection of pixels dots. The raster scan is a scanning technique in graphics monitor where. The aim of the work described in this report has been to apply randomscan display techniques to a system employing a relatively inexpensive rasterscan device. Differences between a raster scan and a random scan.

Random scanning saves on memory as you do not need to store the contents of the entire screen. Computer graphics is an art of drawing pictures, lines, charts, etc. A raster scan approach to computer graphics provides the new opportunity to mix, manipulate, and superimpose photographs and drawings fig. Computer graphics image is made up of number of pixels. There are two ways random scan and raster scan by which we can display an object on the screen. Raster scan and random scan are the mechanisms used in displays for rendering the picture of an object on the screen of the monitor. Difference between raster scan display and random scan. A system which follows random or vector scan displays is called random scan system. In a raster scan system, the electron beam is swept across the screen, one row at a time from top to bottom. The raster scan is a scanning technique in graphics monitor where the. The screen is coated with discrete dots of phosphor. Introduction to graphics systems, basic elements of computer graphics, applications of computer graphics.

Random scan monitors draw a picture one line at a time and so they are also referred to. In a rasterscan system, the electron beam is swept across the screen, one row at a time from top to bottom. Raster scan and random scan systems slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Raster scan approaches to computer graphics sciencedirect. Raster scan monitors draw a picture one line at a time. Architecture of raster scan devices and functions of trackball architecture trackball in a raster scan display, the image which has to be displayed is saved in a binary format 0s and 1s in the refresh buffer memory. Computer graphics solved mcqs computer science solved mcqs. On the other hand, in the random scan, the electron beam is guided on just. Difference between random scan and raster scan display with computer graphics tutorial, line generation algorithm, 2d transformation, 3d computer. Randomscan monitors cannot display realistic shades scenes. Before we begin with what vector graphics and raster graphics are, we must understand a few basic terms.

Sometimes the display processor in random scan system is also known as. In raster scan system electron beam sweeps across the screen, from top to bottom covering one row at a time. As the electron beam moves across each row, the beam intensity is. In a raster scan system, the electron beam is swept across. Unit1 basics of computer graphics darshan institute of. The word raster comes from the latin word rastrum a rake, which is derived from radere to scrape. Raster scan and random scan are the mechanisms used in displays for. Architecture of raster scan devices by palak tandon on prezi. Difference between raster scan system and random scan system base of difference raster. A rasterscan video graphics display system implemented.

Then, a video controller is used to scan each and every line. The main difference between raster scan and random scan lies in the drawing of a picture where the raster scan points the electron beam at the entire screen but incorporating just one line at a time in the downward direction. Rajan babu ap mca department of mca, rgcet randomscan displays in randomscan display unit, a crt has the electron beam directed only to the parts of the screen where a picture is to be drawn. Application areas of computer graphics, overview of graphics systems, videodisplay devices, rasterscan systems, random scan systems, graphics monitors and work stations and input devices.

One of the primary applications of raster scaning technology has been in traditional display devices such as televisions or computer monitors. In computer graphics a pixel, dots, or picture element is a physical point in a picture. Raster can be explained as a rectangular collection of dots or points plotted. Pixel is the smallest addressable graphical unit represented on the computer screen.

Random scan method is well suited for displaying shading and color areas. Raster scan displays are most common type of graphics monitor which employs crt. Raster scan systemaddition to the cpu, special purpose processor, video controller or display controller is used to control the operation of the display device. At the end of each scan line, the electron beam returns to the left side of the screen to begin displaying the next scan line. The computer is an information processing machine and it is a tool for storing, manipulating and corelating data. Difference between raster scan and random scan compare. Pdf difference between raster scan system and random.

Differentiate between raster and random scan displays. Raster scan line drawing algorithm, circle and ellipse drawing algorithms. Computer monitors and tvs use this method whereby electrons are beamed scanned onto the phosphor coating on the screen a line at a time from left to right starting at the topleft corner. Difference between raster scan display and random scan display. Difference between raster scan and random scan in tabular form. In addition to the cpu, a special purpose processor called the video controller or display controller is.

The images are stored as vectors, and the electron gun is used like a pen to draw the images on the tube. The electron beam is directed only to the parts of screen where a. Raster scan system vs random scan system student study hub. By analogy, the term is used for raster graphics, the pattern of image storage and transmission used in most computer bitmap image systems. The lines can be analog representations of the image, or they can be a sequence of pixels in which each dot represents a tiny rectangular area of the image. Pdf difference between raster scan system and random scan. In this tutorial, we are going to learn about the raster scan and random scan display in computer graphics, these scanning methods, and we will also learn each of them in detail. Computer graphics pdf notes free download for mca and b. Pixels or points on the screen can be used to draw any kind of image 3. The components line of a random scan picture must be refreshed in a particular order. A photograph is distinguished from a shape only inasmuch as the filling is no longer a single tone, color, or constant gradation, but an apparently random assortment of gray tones and possible hues.

Televisions in our house are based on raster scan method. The most common form of graphics monitor employing a crt is the raster scan display, based on television technology. Difference between raster scan and random scan with. A field scan direction was selected at random by the computer, and a raster scan was presented at a frequency above the fff 90 hz. Introduction, application areas of computer graphics, overview of graphics systems, videodisplay devices, rasterscan systems, random scan systems, graphics monitors and work stations and input devices. It contains well written, well thought and well explained computer science and. Differentiate between raster scan and random scan displays. These are used to project or exhibit softcopy information in the form of alphanumeric or graphic symbology. Points and lines, line drawing algorithms, midpoint circle and ellipse algorithms. Difference between raster scan and random scantabular form. Define random scan and raster scan displays, computer graphics.

A pattern of illuminated pattern of spots is created by turning beam intensity on and off as it moves across each row. Bae79, the implementation of graphics software for rasterscan systems has lagged behind that for randomscan systems. Raster scan and random scan are the technique used to display the picture of an object on the screen of the desktoppc monitor. Difference between raster scan system and random scan system base of difference raster scan system random scan system electron beam the electron beam is swept across the screen, one row at a time, from top to bottom. In raster scan displays a special area of memory is dedicated to graphics only. Random scan displays random scan display is the use of geometrical primitives such as points, lines, curves, and polygons, which are all based upon mathematical equation. Raster scan in a raster scan system, the electron beam is swept across the screen, one row at a time from top to bottom.

Computer graphics raster scan and random scan display. Graphics systems block diagram of a crt graphics system in this context we discuss the graphics systems of rasterscan devices. In raster scan display, the electron beam is swept across the screen, one row at a time from top to bottom. If you continue browsing the site, you agree to the use of cookies on this website. Raster scan article about raster scan by the free dictionary. In a raster scan displays the electron beam is swept across the screen, one row at a time from top to bottom. Difference between raster scan system and random scan. Computer graphics assignment help, define random scan and raster scan displays, define random scanraster scan displays. The information that is displayed using these two techniques is not permanent which is why it is called softcopy information. Computer graphics lesson 1 an overview of computer graphics, 1 application and interactive graphics lesson 2 raster graphics, basic raster graphics algorithm, 4 scan conversion algo, of line, circle ellipse lesson 3 raster graphics, basic raster graphics algorithm, 6 scan conversion algo, of line, circle ellipse contd graphics hardware lesson 4 graphics display devices, hard. Its resolution is poor because raster system in contrast produces zigzag lines that are plotted as discrete point sets. A raster scan is a method of constructing an image through the use of horizontal lines. As it moves across each row, the beam intensity is turned on and off to create a pattern of illuminated spots.

Computer graphics notes pdf cg notes pdf smartzworld. What is random scan display in crtcomputer answers. A raster scan display is based on intensity control of pixels in the form of a rectangular box called raster on the screen. Information of on and off pixels is stored in refresh buffer or frame buffer. In addition to the cpu, a special purpose processor called the video controller or display controller is used to control the operation of the display device. Raster scan and random scan are two types of display systems that use crt monitors. The growth in the use of such methods has been dependent on rapidly decreasing memory prices and on the availability. Raster scan methods have increasingly become the dominant technology since about 1975.

Lets see hat the difference between random scan and raster scan. For the love of physics walter lewin may 16, 2011 duration. View notes lecture22 crt,raster and random scan displays. The electron beam is directed only to the parts of screen where a picture is to be drawn. Raster scan associates degreed, random scan square measure the. Difference between raster scan system and random scan system base of difference raster scan system random scan system electron beam. Tv sets costlier cost not too high as compared to random scan line drawing,known as vector display mainly used for point plotting 14. Pixels are combined to form a complete image, video, text or any visible thing on a computer display. Computer graphics 7 there are two ways random scan and raster scan by which we can display an object on the screen. In this video we will learn about difference between random scan display and raster scan display in hindi. We must have to consider mathematical formulae, functions to draw image. Difference between raster scan and random scan geeksforgeeks.