Approved by Curriculum Development Centre 51 Oasis Radiant Computer Science, Book 9 applied in designing the mouse. According to the mechanism of using the mouse, we have optical and mechanical types of mouse. Mechanical mouse is an old technology based mouse where one scrolling controls the mouse movement. The optical mouse is based on laser technologies. Scroll wheel mouse has facilities to scroll page in upward and downward direction. Now-a-days we can get wireless mouse that works using electromagnetic waves like the remote controller. Scanner Scanner is an input device. It is used to capture pictures, graphs and other documents in computer and allow these objects to be saved in different formats. It has two main components: • Data capturing sub system: Used to illustrate image and convert into optical form. • Image Processing Subsystem: Used to convert optical image into digital. Its resolution varies from 72 PPI (Pixel Per Inch) to 2400 PPI. Black and white and colour scanners are available in the market at reasonable costs. The cost depends on the resolution of scanner. Types of Scanner Scanner • Flatbed Scanner or Desktop Scanner is the most versatile and commonly used scanner. • Sheet-fed Scanner is similar to flatbed scanner except the document is moved and the scan head is immobile. A sheet-fed scanner looks like a small portable printer. • Handheld Scanner uses the same basic technology as a flatbed scanner. This type of scanner typically does not provide good image quality. However, it can be useful for quickly capturing text. • Drum Scanner is used by the publishing industry to capture incredibly detailed images. They use a technology called a photo-multiplier tube (PMT). In PMT, the document to be scanned is mounted on a glass cylinder.
Oasis Radiant Computer Science, Book 9 52 Approved by Curriculum Development Centre Joystick This is also a pointing device. It is mainly used for interaction with computer games. It consists of a lever, or stick, which is moved by the user and transmits these movements to the computer. It also normally has additional buttons or switches that are used in addition to the stick. Joypad Similar to a joystick, the joypad is designed for gaming input. In many ways it is identical to the joystick, but it uses a multi-directional touch pad in place of the stick. It is most commonly used with games consoles and is suitable for computers. More recent models also have analogue control sticks, used as miniature joysticks. Touch Screen The touch screen is a modern and advanced technology applied in laptop, camera, wrist watch, etc. It is a screen with touch sensitive points or programme icons. When specific point and icon is touched by finger tips, related programmes are activated. There are three types of touch sensitive screen technology. These are capacitive screen, infrared screen and pressure screen. By touching and pressing on such screens, users can give input to the system. Light Pen Light pen is an input pointing device used to draw diagram on VDU (Visual Display Unit) directly. It is connected with VDU. The tip of pen contains light sensitive element which is placed against the screen. The pen operates on two cell batteries. It is used in engineering drawing, architect design, circuit design and other several graphics and art works.
Approved by Curriculum Development Centre 53 Oasis Radiant Computer Science, Book 9 QR Code Scanner It stands for Quick Response Code. The advanced form of Bar Code Reader is QR Code Scanner. A QR code is a pattern of black and white squares. The QR code of any product gives information about the website address. A QR code can be read and processed by a smartphone or a cell phone with the help of Apps or Applications. Microphone Microphone is a sound input device. It helps to input sound or music into the computer in a digital format. It is used in audio chatting and video conferencing through Skype, Viber, Facebook, Messenger, etc. Output Devices The result of processed data is called output. There are two types of output: hard output, which is the result printed on paper, and soft output, which is the result available as visual and audio form. There are different devices used to provide result to the user. These are called output devices. Popular output devices are Printer, Monitor, Plotter, etc. Monitor Most popular and commonly used output device is monitor. It displays the character and graphic on the screen. According to the technology used on the monitor, we have three types of monitor. CRT monitor: Common monitor that uses large vacuum tube called Cathode Ray Tube (CRT) is CRT monitor. It looks like a common TV screen. It is old type of monitor and big in size but cheaper in price. LCD monitor: A flat-panel monitor that uses special kind of liquid crystal to display the character and graphics is called Liquid Crystal Display (LCD) monitor. These are portable in size but more expensive than CRT monitors. It consumes less power than CRT monitor. QR Code
Oasis Radiant Computer Science, Book 9 54 Approved by Curriculum Development Centre LED monitor: A flat panel monitor based on Light Emission Diode (LED) is LED monitor. It is similar to LCD monitor. Printer It is one of the most common hard output devices. It is used to print the result on the paper. Basically printers are divided into two types: Impact printer: Printer that prints the character like a typewriter in which characters are printed by physical striking over an inked ribbon. It is slow and poor quality printer. It is noisy but cheaper for operation. Popular impact printers are Dot matrix printer, Daisy wheel printer, Drum printer, etc. Non-impact printer: Printer that prints the character using heat, light and ink spray technique. It is a quiet printer. It is faster than impact printer. Its quality is good but it is more expensive than impact printer. Popular non-impact printers are: Laser printer, Inkjet printer, etc. Some Popular Printers Inkjet Printers Inkjet printers are non-impact printers which print text and images by spraying tiny droplets of liquid ink on the paper. They are most popular printers for home use. Currently, most inkjet printers use thermal inkjet. The inkjet head design is also divided into two main groups: fixed-head and disposable head. Advantages of inkjet printers • Low cost • High quality of output, capable of printing fine and smooth details
Approved by Curriculum Development Centre 55 Oasis Radiant Computer Science, Book 9 • Capable of printing in different colour, good for printing pictures • Easy to use • Reasonably fast • Quieter than dot matrix printer Disadvantages of inkjet printers • Print head is less durable • Expensive replacement of ink cartridges • Not good for high volume printing • Printing speed is not as fast as laser printers Laser Printers Laser printers are non-impact printers which can print text and images in high speed and high quality resolution. Unlike inkjet printers, laser printers use toner (black or colour powder) instead of liquid ink. A laser printer consists of these major components: drum cartridge, rotating mirror, toner cartridge and roller. Advantages of laser printers • High resolution • High print speed • Good for high volume printing Disadvantages of laser printers • More expensive than inkjet printers • The cost of toner replacement and drum replacement is high • Warm up time needed to print Dot-matrix printer: Dot-matrix printer is an impact printer that produces text and graphics when tiny wire pins on the print head strike the ink ribbon. The print head runs back and forth on the paper like a typewriter. When the ink ribbon presses on the paper, it creates dots that form text and images.
Oasis Radiant Computer Science, Book 9 56 Approved by Curriculum Development Centre Higher number of pins means that the printer prints more dots per character, thus resulting in higher print quality. Dot-matrix printers were very popular and the most common type of printer for personal computer. Advantages of dot matrix printer • Can print on carbon copies • Low printing cost per page • Can be used on continuous form paper • Reliable, durable Disadvantages of dot matrix printer • Noisy • Limited print quality • Low printing speed • Limited colour printing Plotter A popular output device that prints engineering drawing charts and graphics is plotter. It prints high quality drawing and graphics. There are two types of plotters: • Drum plotters • Flat bed plotters Points to remember • Computer is a data processor and its basic operations are input, processing, output and storage. • Central processing unit (CPU) is the main part of computer that consists of three components: memory unit, control unit and arithmetical and logical unit. • Data and instructions are given to the computer system by using input devices. These are scanners, keyboard, mouse, etc. • There are two types of output: hard and soft. • User can get the result by using output devices. These are monitor, printer, plotter, etc.
Approved by Curriculum Development Centre 57 Oasis Radiant Computer Science, Book 9 • Plotters print high quality graphics and drawing. • Printers are common hard output device. There are two types of printers impact and non-impact printers. • Data are stored on the secondary memory. Popular secondary memory are hard disk, floppy disk, zip disk, CD’s, etc. • Storage where we can store data using optical beams is optical storage. These are: CD, DVD, etc. • RAM is the main working memory which is volatile in nature. After switching off the computer, it will be empty. • ROM (Read Only Memory) is a permanent memory which is fixed inside the computer system and data are stored permanently on such memories. It is fixed by Manufacturer Company. Exercises 1. Answer the following questions. a. What is CPU? Explain its components. b. What is a memory unit? Differentiate between primary and secondary memory. c. What are input devices? List any five input devices. d. What is an output device? List any five output devices. e. What is monitor? Write its types. f. What is printer? Describe impact and non-impact printers. g. What is plotter? Write its use. h. What is modem? Write its use. 2. Write short notes on: a. Arithmetic Logic Unit b. Floppy Disk c. Control Unit d. Magnetic tape e. Hard disk f. CD ROM g. DVD ROM h. Memory Unit i. Light pen j. Scanners
Oasis Radiant Computer Science, Book 9 58 Approved by Curriculum Development Centre 3. Differentiate between: a. Input and output b. Primary and secondary memory c. RAM and ROM d. CRT and LCD display e. Hard copy and soft copy f. Hard disk and floppy disk g. Magnetic disk and optical disk h. Impact and non-impact printer i. Printer and plotter j. Scanner and printer 4. Give the full forms of the following a. CPU b. ALU c. RAM d. ROM e. CU f. CRT g. LCD h. Modem i. DVD j. GB k. WORM l. I/O m. BIOS n. XT o. AT p. PPI q. VDU 5. Fill in the blanks. a. Hard disk is ................................ disk. b. CPU consists of ................................. sections. c. LCD monitors are .............................. than CRT monitors. d. Plotter is used in........................................... field. e. Impact printers are similar to the ....................................... 6. State True or False. a. Printer is soft output device. b. Data are stored on RAM. c. Floppy disk is primary memory. d. Full form of CPU is central part unit. e. Modem is used for signal conversions. 7. Class Activity a. Identify the internal components of computer such as RAM, ROM, Hard Disk, Mother Board and Processor. 8. Project Work a. Collect any twenty input and output devices used in a computer system.
Approved by Curriculum Development Centre 59 Oasis Radiant Computer Science, Book 9 Chapter 5 Computer Software ffl Discussion of the concept of computer software ffl Discussion of the types of computer software ffl Explanation of the types of computer hardware ffl Discussion of the relationship between hardware and software THIS CHAPTER COVERS :
Oasis Radiant Computer Science, Book 9 60 Approved by Curriculum Development Centre Computer Software 5 Chapter Introduction We have already discussed that a computer system has four elements. They are hardware, software, human ware and firmware. Hardware is the basic structure of the computer system. To make the hardware active and perform the task at hand we need some programmes. The collection of the programmes which help initiate and control the computer system is called computer software. Programme is the arrangement of instructions in a systematic order to perform some work. These programmes are organised and collected to instruct the computer on what to do and how to do it. For example, software instructs the hardware what to display, what kinds of input are going to be accepted and what kinds of output will be generated. “Software is the collection of programme and other associated documents that helps to control, manage and integrate the components of computer system to accomplish a specific task.” A computer system is nothing without the software. Hardware needs the software, like a car needs a driver, to drive the system smoothly. Hardware and software are complementary to each other. Type of Software In general, we can classify the software into three types. a. System software b. Application software c. Utility software
Approved by Curriculum Development Centre 61 Oasis Radiant Computer Science, Book 9 To restate, software is classified into application software, system software and utility software. But we can also explain the utility software as falling under the system software. a. System Software The software that helps to activate the computer system and provides operating environment for other application software is called system software. Its primary work is to control, integrate and manage the individual’s hardware components of the computer system. It can be explained as different types. These are: i. Operating system (OS) ii. Language Processor i. Operating System: System software that supervises the overall operation of a computer. It provides support functions to the user. It tells the computer how to interact with the user and how to use devices such as disk drives, keyboard, and monitor. Major functions of operating system are: • It manages the jobs waiting to be processed. • It recognises the jobs, identifies their priorities to process.
Oasis Radiant Computer Science, Book 9 62 Approved by Curriculum Development Centre • It manages the storage and retrieval of data. • It is used for virtual memory management. With this software, it is possible to increase the capacity of main memory without actually increasing its size but using secondary memory as primary memory. • It manages the input and output operations of a computer. • Its job is to secure data inside the memory of a computer. It protects hardware and software from improper use. Some large operating systems provide password also for the purpose of security. • It communicates with all the hardware and software components of the computer. • It helps to interpret the command given by the user to the computer system. Most common and popular operating systems are MS-DOS, UNIX, LINUX, Windows, etc. Types of Operating System Based on the mode of user, there are two types of operating systems, they are: i. Single User Operating System: A single user operating system allows only one user to use the computer resources at a time. Such operating systems are generally used by people at home. Most of the operating systems used on microcomputers is a single user operating system such as DOS and Windows. DOS is a single user and single tasking operating system whereas a Windows is a single user and multitasking operating system. ii. Multiuser Operating System: A multiuser operating system allows more than one user to use the computer resources at a time. The resources of the computer may include hardware as well as software components. Multiuser operating systems are used in offices and big companies or organisations where many users can access the same computer at once. It means, multiuser
Approved by Curriculum Development Centre 63 Oasis Radiant Computer Science, Book 9 operating system allows the user to work on a network environment. Some of the examples of multiuser operating system are: UNIX, Novell Netware, Linux and so on. GUI Environment Introduction A GUI (Graphical User Interface) is a computer environment that represents programmes, commands, files, and other options as visual elements, such as icons, pull-down menus, buttons, scroll bars, windows, and dialogue boxes. It helps in simplifying the user interaction with the computer. The graphical user interface (GUI) was introduced to overcome the drawback of Character User Interface (CUI) in which user had to memorise the commands and instruct the computer by typing. Basic Components of GUI GUI based operating systems such MS-Windows and Mac. OS have the following basic components: Desktop : The first screen of Windows, which consists of my computer, recycle bin, control panel, taskbar, start button etc. is desktop. It appears whenever user
Oasis Radiant Computer Science, Book 9 64 Approved by Curriculum Development Centre presses the switch “ON” of the computer system. Icons: A small picture element representing a file programme or command is icon. User can open any programme by taking the mouse pointer over the icon and double clicking the left mouse button. Windows: A rectangular frame which represents different application programmes is Windows. The name is so, as in appearance it looks like a window. User can customise the windows in cascading manner where each window contains different programmes. It can be re-sized, maximised and minimised, too. It also contains horizontal and vertical scroll bars to navigate around.
Approved by Curriculum Development Centre 65 Oasis Radiant Computer Science, Book 9 Dialogue Box: The dialogue box (also called dialog box) is a graphical control element in the form of a small window that communicates information to the user and prompts them for a response. Pointing Device: A device (e.g. a graphics tablet, mouse, stylus, or trackball) used to control the movement of a cursor on a computer screen is a pointing device. It helps the user to point or move any object on the computer screen.
Oasis Radiant Computer Science, Book 9 66 Approved by Curriculum Development Centre Mouse Pointer : A mouse pointer, is a graphical image (generally in the shape of an arrow) that is used to control certain elements in a graphical user interface (GUI). More plainly, it indicates where your mouse should perform its next action, such as opening a programme, or dragging a file to another location. The mouse pointer follows the path of the user’s hand as they move their mouse. The graphic shows an example of a mouse pointer. Activities of mouse pointer It is a symbol used for selecting object on the computer screen. Some of the activities performed by mouse pointers are: Left Click: Left click means pressing the left button of the mouse once. Left click on mouse selects the objects on the screen. Using left click, user can select programmes, files, folders, icons or any other object. Right Click: Right click means pressing the right button of the mouse once. Right click on mouse opens the pop-up menu containing lists of shortcut commands. It provides additional information in the form of drop-down menu. Double-Click: Double click means quickly pressing the left mouse button twice in a quick succession. It is used to open or execute a file, folder, or software programme. Drag and Drop: Drag and drop means pressing and holding the left mouse button and releasing it after moving the mouse to new location. Drag and drop is a pointing device action in which the user selects an object by “grabbing” it and dragging it to a different location or onto another place. Files and Folder Management File: A file is an organised collection of related information stored in a computer. In a GUI environment, an icon of a file indicates its type. If it is an MS-Word application file or MS-Excel file, user can easily identify it by its icon or picture. It is the electronic storage or any information in a computer. Every file has its unique
Approved by Curriculum Development Centre 67 Oasis Radiant Computer Science, Book 9 name and it has two parts: file name and extension, which is separated by a dot( . ). A list of files along with their icon and extension is given below. Folder : A folder, also called a directory, is a special place used to store files, and other folders. The related files are kept in a particular folder so that it helps us to find them easily. A folder is represented by an icon. A folder inside another folder is called a sub-folder. Working with files and folders Creating a new file or folder 1. Right click on the computer screen for creating file or folder. 2. Choose “New” and click at application file name for file and folder for new folder. 3. Type the name of file or folder. 4. Press Enter key. Moving a file or folder (Ctrl+X and Ctrl+V) 1. Right click on the file or folder that you want to move. 2. Click at “Cut” option. 3. Go to the destination location. 4. Right click and choose “Paste” option. Copying and pasting a file or folder (Ctrl+C and Ctrl+V) 1. Right click on the file or folder that you want to copy. 2. Click at “Copy” option. 3. Go to the destination location.
Oasis Radiant Computer Science, Book 9 68 Approved by Curriculum Development Centre 4. Right click and choose “Paste” option. Renaming a file or folder 1. Right click on the file or folder that you want to rename. 2. Click at “Rename” option. 3. Type the new name for file or folder. 4. Press enter key. Deleting a file or folder 1. Right click on the file or folder that you want to delete. 2. Click at “Delete” option. 3. A dialogue box will appear asking you for confirmation. 4. Click at “Yes”.
Approved by Curriculum Development Centre 69 Oasis Radiant Computer Science, Book 9 ii) Language Processor Language processor is the system software that is used to translate the instruction written in a programming language into a machine understandable code. There are three types of language processors. They are:- a) Assembler b) Interpreter c) Compiler a) Assembler: An assembler is a language processor that translates the programme written in assembly level language into its equivalent machine level language. It takes the basic commands and operations from assembly (mnemonic) code and converts them into binary code. Assemblers are similar to compilers as they also produce executable code. A programme written by a programmer in assembly language is called a source programme. When source programme is converted to machine code it is called an object programme. b) Interpreter: An interpreter is a language translator which is used for translating high level language code into machine language code. It takes one statement of a high-level language and translates it into machine instruction and executes it immediately. Interpreters do not create any object programme. c) Compiler: A compiler is a language translator that converts the whole instructions of a high-level language into machine language at once. Compilers are large programmes which reside permanently in the secondary storage. When the translation of the programme is done, they are copied into the main memory of the computer. b) Application Software Application software is a set of one or more programmes which are designed to do a specific task. It is made to fulfill the user’s demand. Application is also called as application package. For example, a payroll package produces pay slips as the output, word processing jobs
Oasis Radiant Computer Science, Book 9 70 Approved by Curriculum Development Centre are done by word processing software (MS-Word) and School Management System processes examination results and produces mark sheets. There are two types of application software. i. Packaged Software ii. Tailored Software a) Packaged Software: It is readymade software developed by a reputed company. It is developed for the global users to perform their generalised tasks. MS-Word, MS-Excel, Photoshop and Corel Draw are examples of packaged software. Some of the common packaged software are: 1. Word processing package: MS-Word, Word Perfect. 2. Spreadsheet package: MS-Excel, Lotus 1-2-3. 3. DBMS package: MS-Access, Oracle, My-Sql. 4. Accounting package: Tally, Fact. 5. Graphical package: Adobe Photoshop, Corel Draw, Freehand. 6. Engineering package: CAD, Auto CAD, CAM. b) Tailored Software: It is also known as customised software. It performs a specific task for the specific person or organisation. It is made to suit the specific requirement of the user. For example, school management system, payroll package, mark sheet preparation and so on. This software is made according to the specific requirements of the organisation or company. Differences between packaged and tailored software. Packaged Software Tailored Software i. The requirement of many organisations and users can’t be perfectly matched. i. The requirement of the user or organisation can be perfectly matched. ii. This software can be trusted as they are made by reputed software houses. ii. These types of software are generally made by local programmers. So, they may contain errors. iii. They cannot be changed easily. iii. They can be changed easily.
Approved by Curriculum Development Centre 71 Oasis Radiant Computer Science, Book 9 iv. They are expensive for small organisations. iv. They are cheap. v. Examples: MS Word, MS Excel, Adobe Photoshop and System and Billing System. V. Examples: School Management System and Payroll. c) Utility Software Utility software is the supporting software which is used to perform specific tasks related to the maintenance of the computer system. Some of the utility software are included in Operating System Software. Some are available as a separate utility in the market. Utility programmes are also called as service programmes. Examples of utility software are Norton utilities, PC tools, WinZip, Partition magic, Backup Utility and Disk Defragmenter. Open Source Software: Introduction Open source software is the software whose source code is freely available to the user. In other words, the software under General Public License (GPL) is open source software. Users can customise the source code of the open source software according to their requirements. They needn’t buy the license in order to use the software. Source code can be modified and redistributed to any other person legally. These software are available free of cost. So, we also call them Free and Open Source Software (FOSS). Examples of open source software are: Linux, Open Office, Apache and Mozilla Firefox. An Introduction to Desktop Application and Web Application Desktop Application: A desktop application runs stand-alone in a desktop or laptop computer. It does not require a web browser or any other platform to run. These programmes should be installed in each computer. They are the machine dependent programmes that
Oasis Radiant Computer Science, Book 9 72 Approved by Curriculum Development Centre run on personal computers like desktop, laptop and personal workstation. Word processors and media players are the examples of desktop applications. Web Application: A web application (web app) is an application programme that is stored on a remote server computer, and with the help of internet and web browser, displayed on client computers. Best examples of web applications are online shopping, E-commerce, online forms, online banking and shopping carts. Common web applications include Gmail, Yahoo and AOL. Popular applications include Google Apps. Comparison between Desktop and Web applications 1. A web application can be accessed from any computer no matter where the person is with the help of internet whereas a desktop app can only be accessed if user has his/her computer. 2. Web applications are costlier than desktop apps. 3. Web applications can be installed only once whereas desktop applications can be installed any number of times on separate computers. 4. Web applications are not reliable as user has to depend on internet for its reliability whereas desktop apps are more secure and reliable. 5. Web applications are platform-independent; they can work in different types of platforms with the help of a web browser whereas desktop applications need to be developed separately for different platform machines.
Approved by Curriculum Development Centre 73 Oasis Radiant Computer Science, Book 9 Points to remember • Set of instructions consisting of one or more programmes that control the operation of a computer system is called software. • System software is software that organises the system and activates it to provide working environment for other application programmes. • Application software is a complete self contained packaged programme designed to perform standard work. • Translator is the programme that converts high level data (user language data) into machine code (computer code). • Device driver introduces the new hardware components to the computer system • Utility software manages the hardware system and tries to maximise the utility of device. • Packaged software is large-scale software developed by software houses. These are used for standard application of office management. • Tailored software is customised software developed for customer’s demand. Exercises 1. Write very short answer for the following. a. Collection of instruction that helps to interact with the computer. b. List different types of software. c. Name the software designed to control the operation of the computer. d. List the major functions of the operating system. e. Based on the mode of user, name different types of operating system. f. Name the operating system where more than one user work at a time. g. Software that gives special service to the user of the computer. h. Name the software that falls under General Public License (GPL.. i. Name any two application software. j. Organised collection of related information. 2. Answer the following questions. a. Compare desktop and web applications. b. Define utility software with example.
Oasis Radiant Computer Science, Book 9 74 Approved by Curriculum Development Centre c. What is open-source software? What is the meaning of FOSS? d. Differentiate between packaged and tailored software. e. Define language processor. List different types of language processors. f. Define File and Folder. g. List different types of mouse activities. h. What is a dialogue box? i. Write the steps for moving and copying a file . 3. Long answer questions. a. What is a GUI environment. List and explain basic components of a GUI based operating system. b. What is software? Write about different types of software in detail. 4. Match the following with appropriate choice. i) Group A Group B a. Cut i. Ctrl + Y b. Copy ii. Ctrl + X c. Paste iii. Assembly Language d. Mnemonic iv. Ctrl + C v. Ctrl + V ii. Group A Group B a. Web Application i. Stand alone computer b. Desktop Application ii. Partition Magic c. FOSS iii. MS-Word d. Utility Software iv. Server Computer v. Open Source Software iii. Group A Group B a. Spreadsheet Package i. MS-Access b. Database Package ii. Photoshop c. Graphical Package iii. Tally d. Engineering Package iv. MS-Excel v. Auto - CAD 5. Class Activity and Project Work a. Collect five example of system software. b. Name any five antivirus software. c. Make a list of any ten application software. d. Make a list of system software, application software and utility software used in your lab.
Approved by Curriculum Development Centre 75 Oasis Radiant Computer Science, Book 9 Chapter 6 Working with Graphics ffl Discussion of different graphics format ffl Discussion of graphics for web ffl Discussion of image size, resolution and editing ffl Discussion of tools of graphics THIS CHAPTER COVERS :
Oasis Radiant Computer Science, Book 9 76 Approved by Curriculum Development Centre Introduction to Computer Graphics Computer graphics refers to the creation, storage and manipulation of pictures and drawings using digital computers. It enhances the communication between computers and users. The term Graphics was derived from the Greek word “Graphikos” which means to present any object having specific shape and size through a medium. Graphics include good quality image or picture, which is not in the form of text or sound. Computer graphics make it easy for us to understand and interpret any topic. A computer graphic has an amazing impact on many types of media and has revolutionised animation, movies and the video game industries. Some of the graphic software are MS-Paint, Freehand, Adobe Indesign, CorelDraw and Adobe Photoshop. Application of Computer Graphics Designing In order to design consumer products and many other applications engineers and architects use graphics. Engineers use CAD (Computer Aided Design) programme to build designs of buildings, cities, aircraft, spacecraft, defence mechanism and so on. Graphics make computer applications interactive, active and dynamic. They open unlimited experimenting options for the designer. Work with Graphics 6 Chapter
Approved by Curriculum Development Centre 77 Oasis Radiant Computer Science, Book 9 2D and 3D image processing and visualisation In 2D and 3D image processing and visualisation of images, Animation, Morphing, Simulation, E-learning and Graphic are playing a vital role. Example: graphic design of a car with 3D picture Animation Uses of Computer Graphics: The following are the common uses of computer graphics in different fields. • Web design • Video game • Computer-aided design (CAD) • Virtual reality • Digital art Different Graphics Formats There are four different types of formats used for storing graphics and images. 1. TIFF (ending in .tif) Its full form is Tagged Image File Format. TIFF are used to store a very large file sizes. They are in uncompressed form and contain a lot of detailed image data. TIFF is the most common file type used in photo software (such as Photoshop). 2. JPEG (ending in .jpg) Its full form is Joint Photographic Experts Group. Files in this format are compressed to store a lot of information in a small size. Most digital cameras store photos in JPEG format. 3. GIF (ending in .gif) GIF stands for Graphic Interchange Format. This format can be used for animations. GIF images cannot be as small as JPEG.
Oasis Radiant Computer Science, Book 9 78 Approved by Curriculum Development Centre 4. PNG (ending in .png) PNG stands for Portable Network Graphics. It also allows for a full range of colour and better compression. It’s used almost exclusively for web images. For photographs, PNG is not as good as JPEG, because it creates a larger file. Graphics for web Images are a vital component of any website, and using the right ones can enhance both your content and design. Graphics used for web site are the representation of an idea or feeling. It can impact the user emotionally or can entertain or educate the user in a very easy manner. There are plenty of tools that can help you create stylish graphics with only a little practice Examples are photographs, drawings, line art, graphs, diagrams, typography (art of arranging letters and text), numbers, symbols, geometric designs, maps, engineering drawings, or other images. Image size and resolution Resolution refers to the number of pixels in an image. Resolution is identified by not only the total number of pixels in the image but sometimes through the height and width of the image as well. For example, an image that is 1500 pixels wide and 1000 pixels high (1500 x 1000) contains 1,500,000 pixels (or 1.5 Megapixels).
Approved by Curriculum Development Centre 79 Oasis Radiant Computer Science, Book 9 Graphic editing Software designed to make changes and modification in the images according to the requirement of the user are graphic editing software. The images can be digital photographs, illustrations, graphs, pictures etc. These software allow the user to remove unnecessary things from the image and add impressive effects to it. There are various graphic editing programmes available in the market: Adobe Photoshop, Microsoft Picture Manager, GIMP (Gnu Image Manipulation Program), photo filter, etc. Adobe Photoshop It is a photo/graphic editing software. This software is specially designed to perform different changes to the pictures like changing the background of the pictures, changing colour, making powerful advertisements, converting boring pictures into eye catching ones and so on. Adobe Photoshop is one of the popular graphics design and image-editing software developed by American brothers Thomas Knoll and John Knoll at Adobe Company in 1988. It is very useful for professional desktop publishers, web designers, digital photographers, videographers, etc. to carry out image manipulation and printing. Features of Photoshop Some of the features of Adobe Photoshop are as follows: 1. It is easy and effective for creating and editing images.
Oasis Radiant Computer Science, Book 9 80 Approved by Curriculum Development Centre 2. It provides several tools to perform the image task quickly. 3. It supports 2D to 3D image conversion. 4. It allows saving images for the web. 5. It allows formatting and printing of images in the desired style. The list of the common tools with their function in photoshop is given below: Icon Tool Name Use Move (V) Moves selections or layers. Marquee (M) Makes rectangular, elliptical, single row, and single column selections.
Approved by Curriculum Development Centre 81 Oasis Radiant Computer Science, Book 9 Lasso (L) Makes freehand, polygonal (straightedged), and magnetic selections. Quick Selection (W) Make selections by painting. Crop (C) Crops an image. Eyedropper (I) Samples pixels. Spot Healing (J) Removes imperfections. Brush (B) Paints the foreground colour. Clone Stamp (S) Paints with a sample of the image. History Brush (Y) Paints with the selected state or snapshot. Eraser (E) Erases pixels—or reverts to a saved history state. Gradient (G) Creates a gradient.
Oasis Radiant Computer Science, Book 9 82 Approved by Curriculum Development Centre Blur (no shortcut) Blurs pixels. Dodge (O) Lightens pixels in an image. Pen (P) Draws a vector path. Horizontal Type (T) Creates a type layer. Path Selection (A) Allows you to manipulate a path. Rectangle (U) Draws vector shapes. Hand (H) Navigates the page. Zoom (Z) Increases and decreases the relative size of the view. Marquee Select Tool:- This tool selects a part of picture in different shapes. Steps to use this tool are as follows: Step 1 - Click on “Select tool” on the tool box. Step 2 - Click and drag over the picture in order to select a part.
Approved by Curriculum Development Centre 83 Oasis Radiant Computer Science, Book 9 Step 3 - Selected part will be seen as indicated with dotted lines in the picture. Move tool:- This tool is used to move the selected part or any other object in the picture to new location. Steps to use this tool are as follows: Step 1 - Click on “Move tool” on the tool box. Step 2 - Click and drag the selected part of the picture. Step 3 - Move it to the new location as shown in the picture.
Oasis Radiant Computer Science, Book 9 84 Approved by Curriculum Development Centre Lasso tool:- This tool is used for free selection of image. Steps to use this tool are as follows: Step 1 - Click on “Lasso tool” on the tool box. Step 2 - Click and move the pointer freely to any part of the picture. Step 3 - Selection should end at the same point from where you have started. Step 4 - A free selected portion will be seen with dotted line as shown above. Magic wand tool:- The Magic Wand tool selects similar colour portion of the picture. This tool helps in removing the background part of the picture. Before using this tool the lock over the layer must be removed by double clicking over the lock and clicking OK. Steps to use this tool are as follows: Step 1 - Click on “Magic Wand tool” on the tool box. Step 2 - Click over a colour in the picture and press delete key. Step 3 - In this way keep on selecting the similar colour background from the
Approved by Curriculum Development Centre 85 Oasis Radiant Computer Science, Book 9 image and remove it by pressing delete key. Step 4 - The whole background can be deleted in this way and user can keep a new background in the picture. Crop tool:- Crop tool is used to select and cut a portion of the image. It helps in reducing the size of the image. Steps to use this tool are as follows: Step 1 - Click on “Crop tool” on the tool box. Step 2 - Select the portion of the picture. Step 3 - Press enter to get the selected portion only as shown above.
Oasis Radiant Computer Science, Book 9 86 Approved by Curriculum Development Centre Text tool:- Text tool is used to write some text or words over the picture. Steps to use this tool are as follows: Step 1 - Click on “Text tool” on the tool box. Step 2 - Select a portion over the picture, where user wants to type. Step 3 - Start typing over the picture. Eraser Tool:- The eraser tool consists of three sub types, Eraser, Background Eraser and Magic Eraser. Eraser erases the whole picture, background eraser erases background and magic eraser erases similar colour portions like magic wand. Steps to use this tool are as follows: Step 1 - Click on “Erase Tool” on the tool box. Step 2 - Right click and choose one of the options like “Background Eraser Tool”. Step 3 - Drag over the picture to erase the background as shown above.
Approved by Curriculum Development Centre 87 Oasis Radiant Computer Science, Book 9 Gradient Tool:- Gradient tool is useful in creating banners as it fills shaded colour at the background. Steps to use this tool are as follows: Step 1 - Click on the “Gradient Tool” on the tool box. Step 2 - Drag across the image. Step 3 - Move towards left to right or right to left to determine the flow of gradient
Oasis Radiant Computer Science, Book 9 88 Approved by Curriculum Development Centre Pen Tool:- The pen tool is used to select the specific portion of the picture. Steps to use this tool are as follows: Step 1 - Click on the “Pen Tool” on the tool box. Step 2 - Move over the picture vertically and horizontally to select the required portion. Step 3 - Result will be as shown above. Slice Tool:- The slice tool is used to divide an image into different sections, and these separate parts can be used as pieces. Steps to use this tool are as follows: Step 1 - Click on the “Slice Tool” on the tool box. Step 2 - Click and drag over the picture. Step 3 - Picture will be divided into different slices or parts. Step 4 - Now we can save sliced part as a separate file.
Approved by Curriculum Development Centre 89 Oasis Radiant Computer Science, Book 9 Dodge Tool:- The dodge tool is used to remove the darkness of the image and make it bright or lighten it. Steps to use this tool are as follows: Step 1 - Click on the “Dodge Tool” on the tool box. Step 2 - Move the pointer over the picture by pressing the left button. Step 3 - Picture will be seen brighter over the rubbed portion.
Oasis Radiant Computer Science, Book 9 90 Approved by Curriculum Development Centre Note Tool:- The note tool is used to type note or reference text about the existing picture . Steps to use this tool are as follows: Step 1 - Click on the “Note Tool” on the tool box. Step 2 - Drag over the picture to create a box as shown above. Step 3 - Now type over the notepad. Zoom Tool:- Zoom tool is used to zoom in the picture as if user is looking through a magnifying lens. Steps to use this tool are as follows: Step 1 - Click on the “Zoom Tool” on the tool box. Step 2 - Click the left mouse button to zoom the image. Step 3 - The enlarged picture will be seen as shown above.
Approved by Curriculum Development Centre 91 Oasis Radiant Computer Science, Book 9 Hand Tool:- The hand tool is used to move the image horizontally or vertically. Steps to use this tool are as follows: Step 1 - Click on the “Hand Tool” on the tool box. Step 2 - Click on picture or text then drag the mouse pointer. Path Selection Tool:- The path selection tool is used to change or transform the direction of the image picture. Steps to use this tool are as follows:
Oasis Radiant Computer Science, Book 9 92 Approved by Curriculum Development Centre Step 1 - Click on the “Path Selection Tool” on the tool box. Step 2 - Now drag the mouse pointer over the picture. Step 3 - Navigation tool box will indicate the direction of your pointer both vertically and horizontally. Clone tool:- Clone tool helps create a cloning image or duplicate image over the same picture. Steps to use this tool are as follows: Step 1 - Click on “Clone Tool” on the tool box. Step 2 - Press alt key over the portion of image whose cloning user wants to do.
Approved by Curriculum Development Centre 93 Oasis Radiant Computer Science, Book 9 Step 3 - Move over the picture by pressing the left button. Step 4 - Duplicate image will be created in new location as shown above. Image Editing:- Adobe Photoshop is full of image editing features. Some of them are Resizing, Setting brightness, Rotating image, Saving image, Scanning image and Printing image. Resizing an image This option is used for changing the size of image according to the dimensions given by the user. User can supply the different values for width, height, resolution etc. Steps to use this tool are as follows: Step 1 - Open the image whose size user wants to change. Step 2 - Click on “Image Menu” then choose “Image Size”. Step 3 - “Image Size” dialogue box appears over the image. Step 4 - Specify the width and height in percent or pixels and resolution as per requirement. Step 4 - Click “OK” button to accept the changed dimensions as shown above.
Oasis Radiant Computer Science, Book 9 94 Approved by Curriculum Development Centre Setting Brightness on an Image:- User can set brightness and contrast on the image according to his/her own choice. For doing so, follow the steps given below: Step 1 - Open the image to change the brightness or contrast. Step 2 - Click on “Image Menu” then choose the “Adjustments” option followed by “Brightness/Contrast”. Step 3 - “Brightness/Contrast” dialogue box appears. Change the brightness and contrast according to requirement. Step 4 - Click on “OK” button. Rotate or Flip Image This option is used for turning the image upside down or from left to right. Steps to flip the image are as follows: Step 1 - Open an image you want to rotate or flip.
Approved by Curriculum Development Centre 95 Oasis Radiant Computer Science, Book 9 Step 2 - Click on “Image Menu” . Again click on “Rotate Canvas”. Step 3 - Choose one of the options like “1800 , 900 CW, 900 CCW” Step 4 - Result will be as shown above of 1800. Saving Images for the web:- In Photoshop we can save any image in a good quality for web sites. Web sites supports two types of images .GIF (Graphic Interchange Format) and .JPEG (Joint Photographic Expert Group). JPEG is of high quality in comparison to GIF. Steps to save the image for web are as follows: Step 1 - Open the image which user wants to save for web site. Step 2 - Click on the “File Menu”. Step 3 - Click on “Save for Web” option. Step 4 - Save for Web and Device dialog box appears on the screen. Step 5 - Click on “Save”. A dialogue box appears, type name, select location and finally click on “Save”. Scanning Photos Using Scanner:- Images can be easily scanned through Photoshop, users need not install separate scanner in a computer. Photos, pictures, graphics, plain text etc. can be scanned and edited using the scanner effectively in Photoshop. To scan and edit picture in
Oasis Radiant Computer Science, Book 9 96 Approved by Curriculum Development Centre Photoshop follow these steps. Step 1 - Keep the photo or picture on the scanner. Step 2 - Click on “File Menu” then select the option “Import”. Step 3 - Select the name of your scanner from sub options of import like brother DCP J100. Now scanning windows screen will appear. Step 4 - Click on preview button. Step 5 - Click on colour mode combo box and choose the required colour mode such as RGB, black, white, Grayscale etc. Step 6 - Click on scan button. Now scanning progress dialogue box appears and after few seconds the photo will be seen on the Photoshop window. Step 7 - Now save the scanned photo. Printing Image Document:- The image created, edited and formatted can be printed from printer to produce hard copy output for future use. To print a Photoshop document follow these steps: Step 1 - Open the Picture or Image to print. Step 2 - Click on “File Menu” then select the option print. Now print dialogue box will appear as shown.
Approved by Curriculum Development Centre 97 Oasis Radiant Computer Science, Book 9 Step 3 - Supply print range for printing. Step 4 - Supply number of copies. Step 5 - Select other options from the dialogue box such as document properties and give the values. Step 6 - Click on Finish tab. Step 7 - Click on print on both sides if the document is to be printed on both the sides. Step 8 - Finally click on “OK” button. Now the document will be printed on the paper.
Oasis Radiant Computer Science, Book 9 98 Approved by Curriculum Development Centre Exercises 1. Write very short answers for the following. a. Name the Greek word from which the term Graphics was derived. b. Name any two media that have revolutionised computer graphics? c. Name the application used by engineers to build designs of buildings and cities. d. List some of the fields playing a vital role in processing of 2D and 3D images. e. The image format which is in an uncompressed form and contains a lot of details. f. Name the image format used for animation. g. An image that is 3500 pixels wide and 2500 pixels high contains, how many Megapixels. h. Who developed Adobe Photoshop and in which year? i. Name the tool which makes freehand selections. j. Name the tool which navigates the page. k. Image format made up of 256 colours or less. l. Name the tool which creates a duplicate image. m. Name the tool which looks like a magnifying glass. n. Name the tool used to type reference about the image. o. Name the tool which divides the image into different sections. p. Name the tool which is helpful in creating a banner. q. Number of pixels in an image. 2. Answer the following questions in short. a. What is computer graphics? List some graphics software. b. Write any four uses of computer graphics. c. What is Adobe Photoshop? List some popular photo editing software. d. How can graphics for web impact the user? List some examples of web graphics. e. Name different graphic formats with their full forms.
Approved by Curriculum Development Centre 99 Oasis Radiant Computer Science, Book 9 f. Write some of the features of Adobe Photoshop. g. Write the uses of following Photoshop tools. i. Clone ii. Eraser iii. Lasso iv. Magic Wand 3. Long Answer questions. a. List any 10 tools of Adobe Photoshop with their uses. b. Adobe Photoshop is a popular photo/graphic editing software. Justify this statement by giving a few examples from day to day life. 4. Select the best alternative from the given choices. a. Which of the following is not a graphic software. i. MS-Paint ii. MS-Word iii. Freehand iv. None b. Which of these is not a graphic format? i. .TIFF ii. .GIF iii. .JPEG iv. .MDB c. Which is not a graphic format ? i. Photograph ii. Text iii. Diagram iv. Flowchart d. Which of the following is not a photo Editing Programme? i. Photo filter ii. Photoshop iii. MS-Word iv. All e. Which tool draws a vector path? i. Pencil tool ii. Pen tool iii. Eraser tool iv. Zoom tool f. Which tool helps in cutting a part of the image? i. Paste Tool ii. Crop Tool iii. Part Tool iv. Cut Tool g. Eye dropper tool is used to ....................... i. drop colour ii. select a colour iii. drop colour to eye iv. None. h. We can also scan pictures through Photoshop. i. Only sometimes ii. Never iii. Always iv. Not i. Resolution of image is measured in.................... i. dpi ii. ddi iii. isi iv. bsi j. Which is the option for image rotation? i. 900 CW ii. CCW iii. 1800 CW iv. All
Oasis Radiant Computer Science, Book 9 100 Approved by Curriculum Development Centre 5. Match the following with appropriate choice. i. Group A Group B a. Free hand i. To type character. b. Clone Tool ii. To navigate the photo. c. Text Tool iii. Graphic software. d. Hand Tool iv. To fill more than one colour. v. To make duplicate. ii. Group A Group B a. Eraser Tool i. To divide image into different sections. b. GIMP ii. Select picture based on colour. c. Slice Tool iii. To bring lightness on the image. d. Magic Wand Tool iv. To remove part of image. v. Photo Editing Software. iii. Group A Group B a. Move Tool i. Uses of Graphics. b. Virtual Reality ii. Graphics for web. c. Zoom Tool iii. Adobe Photoshop. d. Design and patterns iv. To view image in Larger mode. v. To make duplicate image. 6. Write the name of the following tool with their function. Took Name Functions