INTRODUCTION TO RASTER GRAPHICS Emily Scoggins Wakefield High

INTRODUCTION TO RASTER GRAPHICS Emily Scoggins Wakefield High School Raleigh, NC

2 TYPES OF GRAPHICS Vector Raster

EXAMPLES OF RASTER GRAPHICS

RASTER GRAPHICS • Also called Bitmap Graphic • Raster graphics are from small squares of specified color called Pixels on a grid to create a graphic image • Best for Photography • Loses clarity when zoomed in • Edited in Painting programs • ex. Adobe Photoshop or Paint

WHY USE RASTER GRAPHICS? • Best for Photographs or photo-realistic images • Supports complex color or full color • Can be compressed easily

DISADVANTAGES OF RASTER GRAPHICS • Larger file size • Depending on resolution, the higher, the larger the file size • Resolution Dependent • As you increase the size of a Bitmap image, the resolution will reduce • Resizing images can reduce quality • Information is lost each time a bitmap is saved

RASTER FILE FORMATS • . JPEG – Joint Photographic Experts Group • Typically used for photographs and complex images • Full color, but loses quality as you zoom in • Most popular file type for images • . PNG – Portable Network Graphic • Supports complex transparency, higher quality • . GIF – Graphics Interchange Format • Simple images, only 256 colors but supports simple transparency