Computer Graphics Unit 23 Computer Graphics

Computer Graphics Computer generated imagery can be categorized into several different types: Vector or Bitmap (Raster) images 2D or 3D Still or animated graphics

Vector Graphics

Vector graphics are re-scalable - they are comprised of shapes mathematically defined by curves and points. When vector images are stretched, they will redraw themselves and still look good

Vector Graphics Software Here are some of the best applications which can create vector graphics: Adobe Illustrator (similar to Adobe Photoshop) Adobe Flash (formally owned by Macromedia) CorelDRAW Some other vector applications: Serif DrawPlus Inkscape (free, download) MS Visio (mainly charts and diagrams) Google Sketchup Google SketchUp Sketch-Up enables you to draw fast 3D models. Sketch-Up tools are simple and allow many 3D effects.

Illustrator is a professional level vector graphics application for graphic design, static images. In 2013, the current version is CS6 (CS = Creative Studio) Adobe Illustrator (vector graphics)

Adobe Flash Flash “movies” are graphics, text, animation, and applications for Web sites. They consist primarily of vector graphics, but they can also contain imported video, bitmap graphics, and sounds. In order to view a Flash “movie” on web page or as a standalone file, it must be save in shockwave format (swf, pronounced “swiff” - these swf files are much smaller and save space)

SWF file example (Click on the image)

Flash is used to create web pages, animated graphics as well as static 2D images. It works with vectors, but images can be exported to bitmap format. Flash (vector graphics)

Blender 3D Blender is a free and open-source 3D computer graphics software product used for creating animated films, visual effects, interactive 3D applications or video games.

Blender is powerful computer graphics software and free to download and use. It has been used in creating films and advertisements in the media industry Blender 3D - Computer Graphics

Clip art is a vector graphic, and can be found in Office software and in web libraries, such as this daffodil found in the openclipart.org website (available to share) Clip Art

Vector Graphics These have: Generally small file size (except AI format) Crisper edges. File formats (file extensions) include: SVG - Scalable vector graphics (opens in web browser) - a universal format, used for clipart AI - Illustrator file (can become very large) WMF, EMF (Windows/Enhanced Metafile - used for clipart) PDF (Portable Document Format) - any file (image or text) can be converted into this - viewable on web browser or in any PDF reader - PDF printers available online to convert files to PDF

Vector Graphics File formats (file extensions) also include: FLA - Flash files use this file extension. Here are some examples of different vector file types, showing the file extensions on the end:

Bitmap Graphics

Bitmap Graphics Software Here are some of the best applications which can create bitmap/raster graphics: Adobe Photoshop GIMP (free) Corel PaintShop Photo (formally Jasc Paintshop Pro) Some other useful bitmap applications: Irfanview (free, very useful for quick edits) Paint (simple) MS Picture Manager (inside the MS Office tools folder) Adobe PhotoShop PhotoShop, like Illustrator, will allow you creative freedom to accomplish tasks (e.g. background removal, layering, cloning, etc.) Cloning

GIMP GIMP is a free bitmap graphics editor software and has many interesting features to help you be creative with images.

IrfanView Irfanview is a free bitmap graphics application. It opens quickly so you can make swift changes. It also has several built in “Macro” functions such as creating a web gallery, batch changes (e.g. apply a change to a folder of images) and even plays media.

Bitmap Graphics/pixels Bitmap graphics are made of square pixels so when resized suffer from “pixelation”, e.g. on down-sizing, text can become distorted (a “d” becomes more like an “a” etc.) Pixelation

Bitmap/Raster images Advantages/disadvantages: Very portable, easy to edit, versatile Pixelation when image stretched or shrunk Some file formats offer file size compression The two most popular file formats are: JPG(JPEG) - photographic use (compressible) GIF (Graphics Interchange Format) - max 256 colour palette, therefore better for “flat” images such as logos and graphics. Can also animate

Bitmap/Raster images Other bitmap file formats are: PNG (Portable Network Graphic) - combines advantages of JPG and GIF. Not as popular though TIF (Tagged Interchange Format) - retains the quality though file sizes much bigger BMP (Bitmap format) - a basic format which is universal though not compressible as GIF Here are some different files showing with the extensions: butterfly.gif

Tutorials Flash resources

Search for any content (any media): Search for clipart: Creative Commons