IT_Chapter_8B

Graphic File Formats

• Bitmapped images

– Most common image type

– Also called raster images

– Image is drawn using a pixel grid

– Each grid contains a color

– Color depth

• Number of usable colors

– Used to store drawings or photographs

– Resizing image can reduce quality

• Vector images

– Drawn using mathematical formulas

– Formulas describe the line properties

– CAD and animation software

– Resizing image will not reduce quality

• File formats and compatibility

– Method for storing an image

– Each method has pros and cons

– Some formats are proprietary

– Graphic software can handle all formats

• Common bitmapped file formats

– BMP

– EMF

– GIF

– JPG

– PICT

– PNG

– TIFF

• Vector file formats

– Most vector formats are proprietary

– Two universal formats exist

– DXF

– IGES

Acquiring Images

• Scanners

– Like a photocopier

– Image is saved onto disk

– Scanners import a variety of formats

• Digital cameras

– Stores digitized images

– Uses long term storage

– Image is usually a JPG file

• Digital video cameras

– Stores full motion video

– Uses long term storage

– Movie can be transferred to DVD

• Clip art

– Originally a book with images

– Now a CD with images

– Most office suites include a selection

– Additional clip art is online

Graphics Software

• Paint programs

– Create bitmap images

– Includes sophisticated tools

– Artists draw with several brushes

– Objects drawn become permanent

– Windows Paint

• Draw programs

– Create vector based images

– Used when accuracy is critical

– Objects have an outline and fill

• Both have line style and color

• Can fill using pictures

– Adobe Illustrator

• Photo-editing software

– Modify and manipulate digital images

– Work at the pixel level

– Images can be enhanced

– Picture flaws can be repaired

– Pictures can be completely changed

– Photoshop and GIMP

• Computer Aided Drafting (CAD)

– Generates vector files

– Engineering and design fields

– Drawings accurate to the millimeter

– AutoCAD

• 3D modeling software

– Generates three dimensional images

– Image can be shaped on screen

– Image is animated frame by frame

• Computer generated imaging

– Generates photo realistic images

– Used for movies and television

– Software eliminates tedious parts

Multimedia Basics

• Medium

– Way of sharing information

– Voice, pictures, text

– More effective with multiple mediums

– Multimedia presents information with one medium

• Interactivity

– Users and program respond

– Users can control the content

– Main difference between TV and computer