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Devi Balika Vidyalaya , Colombo ICT ( O/L) Seminar - Multimedia Technology. By Informatics Institute of Technology. Multimedia. Using more than one medium of expression or communication. Text Images Audio Video Animation. Image. A picture represented in computer. Binary Image
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Devi BalikaVidyalaya, ColomboICT (O/L) Seminar - Multimedia Technology By Informatics Institute of Technology
Multimedia Using more than one medium of expression or communication. • Text • Images • Audio • Video • Animation
Image • A picture represented in computer. • Binary Image • Gray Scale • Colour Image
Colour Models • Ways of representing colours in digital devices. • RGB (Red, Green, Blue)Used for display devices like TV, Computer Display, Projectors. • CMYK (Cyan, Magenta, Yellow, Black)Used for printing.
Pixel • Smallest unit of area on a display device, or a printed image. • A pixel can hold one colour • An image is a collection of pixels. 4X4 pixels
Resolution • Refers to the sharpness and clarity of an image. The term is most often used to describe monitors, printers, and bit-mapped graphic images. • In the case of dot-matrix and laser printers, the resolution indicates the number of dots per inch. (For example, a 300-dpi (dots per inch) printer is one that is capable of printing 300 distinct dots in a line 1 inch long. This means it can print 90,000 dots per square inch.)
Image Activity • Use colour picker to identify different colours represented by RGB and CMYK. • Range of vales each of R, G and B represent In decimal from 0 to 255In Hexadecimal from 00 to FF • Amount of memory required for representing each of R, G and B = 224 bytes
Factors effecting file Size of an Image • Width • Height • ResolutionHow many pixels are there in one square image. Measured in Dots per inch (dpi), Pixels Per Inch (ppi). • Memory allocated for colour informationIn RGB colour mode 3 bytes for a pixel. E.g. Size=Width (inch) x Height (inch) x Resolution (ppi) 2x Memory allocated for one pixel
Quality of an Image • Width • Height • Resolution • Colour Mode
Lossy and Lossless file compressions • Lossless and lossy compression are terms that describe whether or not, in the compression of a file, all original data can be recovered when the file is uncompressed. With lossless compression, every single bit of data that was originally in the file remains after the file is uncompressed.
What is GIMP? The term GIMP stands for GNU Image Manipulation Program. This is an open source software for image manipulation. It is multi-platform application; which gives you the ability to run the program across platforms like Linux, Windows and even Apple computers!
Features of GIMP • Simple image drawing tool which uses brushes, pencils and erasers • Paint program which support layers for easy image creation • Photo re-touching tools • Convert images to different formats • Built-in library of tools and plugins for advanced image manipulation
How to open GIMP? • Double click the Gimp shortcut icon on your desktop
Program interface… Title bar • Shows the name of the currently opened or working file Menu bar • Contains menu options for available tools and other program preferences Tool Options • This panel changes according to the selected tool in the toolbox. We can use this to panel to change options for the selected tool
Program interface… Brushes, Patterns and Gradients • Click on each tab to view available Brushes, Patterns and Gradient
Program interface… Layers, Channels, Paths and Undo • The first tab, the layer panel shows the structure of the currently active image, and allows it to be manipulated in a variety of ways. Click on each tab and observe. Advantages of using Layers • Ability to rework previous edits, flexibility, organization and applying effects are some of the advantages of using layers.
Toolbox • Let’s get to know the different tools available in the tool box. We only going to learn the most important and basic tools available.
How to create a new image • Select the menu option File New • Click on the down arrow in the template section and select a preset size or • Type a number for the width and height • Click on OK Getting a new canvas will load the horizontal and vertical rulers to the screen
How to save an image • Select the menu option File Save (Shortcut Ctrl + S) • Select a location • Type a name for the file • Click on Save
How to open an image • Select the menu option File Open (Shortcut Ctrl + O) • Select a location • Click on the needed file • Click on Open
How to close an Image • Select the menu option File Close view (Shortcut Ctrl + W) How to close an Image • Select the menu option File Quit (Shortcut Ctrl + Q)
Menu Bar This is the standard menu bar which provides operations such as saving files, closing files, exit application, cut and paste, etc.
Tools Options This is a special panel which change according to the tools you select in Tool Box. This panel will show you additional options for the selected tool
Brushes Panel This panel gives the option to select different shape for the brushes. Based on the selected brush, the drawing may change.
Patterns Panel This panel comes with some built-in options to fill the drawing with patterns.
Gradient Panel This panel has some predefined gradient styles which can be directly apply on the drawings.
Layers Layers are like a stack of sheets. You can see through transparent areas of a layer to the layers below. You can change the content of a layer without effecting the contents of the other layers. You can also change the opacity of a layer to make content partially transparent. • Name • Sets • Visibility • Opacity • Fill
Layers Panel This panel will display the multiple layers of your working image (if you have such).
Opacity • Opacity (pronounced "o-PASS-ity") refers to the opaqueness of an object. In computing, opacity is often used in graphics software to define how "nontransparent" an image is. In other words, the more transparent an image or image layer is, the lower its opacity level.
Image File Types • Support more colours • BMP • TIFF • TGA • Support smaller file size • JPG • GIF • PNG