Graphics

Objectives Explain why graphic images are vital to multimedia applications List the different ways graphics can be used in multimedia applications Describe the different technologies that can be used to capture digital images List several sources of still images List the four items that should be logged in reference to graphic images Discuss the responsibilities of a graphics designer Define common terms used in computer graphics Describe some of the common tools found on a tool palette

Objectives Explain the difference between paint programs and draw programs Explain the difference between bitmapped graphics and vector-based graphics Describe several features of common graphics programs Explain jaggies and how they occur Explain the process of creating 3D graphics Discuss the different types of images that can be used in a multimedia application Discuss the two different types of resolution related to graphic images Explain several disadvantages of high resolution graphics Discuss copyright law as it applies to graphic images

Introduction backgrounds buttons icons navigation bars charts/graphs Photographs 3D

Digitized Images converting images into a format the computer can understand series of 0’s and 1’s

Methods of Creating Graphics Draw Programs Paint Programs Scanners Video Capture Cards Snappy Photo CD

Types of Images Line Art - black and white/flat colors Grayscale - 256 levels of gray Color - 4-bit to 36-bit (RGB) 2D or 3D - (3D Web = VRML or Live3D) Hypergraphics - (image map)

Image Quality bit or color resolution number of colors in each pixel also called bit or pixel depth most common ranges are 8-, 16-, and 24-bit images with greater bit resolutions will be more colorful and of higher quality image resolution (measured in ppi) amount of information stored for each image

Image Compression compression - an algorithm used to create smaller file sizes lossy - expendable data is actually lost lossless - none of the data is actually lost; mathematical algorithms eliminate redundant data.

Graphics Software Paint Programs and Bitmapped Graphics Features stored as pixels pixels record the screen location and color value on a bitmap jaggies/staircasing Features Geometric Figures Edit Add Color and Patterns Cut and Paste Rotate and Stretch

Graphics Software Draw Programs and Vector Graphics Features vector-based images - created and recreated from mathematical models Features Fully Editable Shapes Bézier Curves Gradient Fill Blending Grouping Objects Rasterize

Graphics Software 3D Modeling Programs Features 3D objects - created using geometric forms or wire frame models surfaces/textures are mapped to the models rendering - converting 3D images to 2D Features Modeling Arranging and Deforming Objects Shading Setting Lights and Cameras Rendering

3-D Drawing 3-D software usually offers: Directional lighting Motion Different perspectives

3-D Drawing 3-D objects combine various shapes

3-D Drawing Shapes can be extruded…

3-D Drawing …or lathed

A scene can use different types of shading 3-D Drawing Gourand shading Flat shading Ray tracing Phong shading A scene can use different types of shading

Graphics Software Image Editing Programs Features manipulate existing images Features Cropping Brightness, Contrast, and Color Correction Filters Layering File Format Conversion Image Enhancement Plug-Ins

File Formats TIFF (Tagged Image File Format) EPS (Encapsulated PostScript) BMP (short for Bitmap) DIB (Device-Independent Bitmap) GIF (Graphics Interchange Format) PCX PICT/PICT2 (short for Picture) JPEG (Joint Photographic Experts Group)

File Formats TARGA Photoshop Native MacPaint PIC PCD (Photo CD) Plot File AutoCAD Windows Metafile (WMF) Word Perfect Graphics (WPG)

Sources of Still Images Commercial Image Providers/Stock Photography Houses Clip Art Photographs Digital Video Charts Maps

Copyright assume an image is copyright protected 1976 Federal Copyright Act property of the creator to 50 years beyond his or her life. if the creator is a corporation or business, up to 75 years after publication or 100 years following creation, whichever is shorter.

Copyright Public domain images can be manipulated and used without permission from the artist and without having to pay the artist any royalties for using them Fair use policy - instruction/education exclusions

Copyright Summary The only time you can alter or manipulate images is if: you receive permission from the original artist you create the image yourself the image is clearly public domain the image is being used strictly for instructional purposes in an educational setting

Example